Download Preview the material

Planning And
Implementing Critical
Care And Emergency
Pharmaceuticals
Jassin M. Jouria, MD
Dr. Jassin M. Jouria is a medical doctor, professor of
academic medicine, and medical author. He
graduated from Ross University School of Medicine
and has completed his clinical clerkship training in
various teaching hospitals throughout New York, including King’s County Hospital Center
and Brookdale Medical Center, among others. Dr. Jouria has passed all USMLE medical
board exams, and has served as a test prep tutor and instructor for Kaplan. He has
developed several medical courses and curricula for a variety of educational institutions. Dr.
Jouria has also served on multiple levels in the academic field including faculty member and
Department Chair. Dr. Jouria continues to serves as a Subject Matter Expert for several
continuing education organizations covering multiple basic medical sciences. He has also
developed several continuing medical education courses covering various topics in clinical
medicine. Recently, Dr. Jouria has been contracted by the University of Miami/Jackson
Memorial Hospital’s Department of Surgery to develop an e-module training series for
trauma patient management. Dr. Jouria is currently authoring an academic textbook on
Human Anatomy & Physiology.
Abstract
Safe administration of medication in critical care and emergency settings is
paramount to ensure optimal outcomes for patients. The most experienced
medical and nursing clinicians are well aware of the fragility of critical care
patients and the potential for the smallest mistake to result in serious
consequences. Understanding the purpose, administration, monitoring, and
potential consequences of pharmacological agents available to critical care
and emergency department clinicians is necessary for them to make use of
potentially life-saving treatments.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
1
Policy Statement
This activity has been planned and implemented in accordance with the
policies of NurseCe4Less.com and the continuing nursing education
requirements of the American Nurses Credentialing Center's Commission on
Accreditation for registered nurses. It is the policy of NurseCe4Less.com to
ensure objectivity, transparency, and best practice in clinical education for
all continuing nursing education (CNE) activities.
Continuing Education Credit Designation
This educational activity is credited for 4 hours. Nurses may only claim credit
commensurate with the credit awarded for completion of this course activity.
Pharmacology content is 4 hours.
Statement of Learning Need
Critical care and emergency medicine is a relatively recent phenomenon in
health care, and the role of pharmacists, physicians and certified nurses
trained to work in critical care and emergency settings have expanded over
recent years. As the intensive care units and emergency departments in
hospital increasingly develop to include computerized equipment and
software supporting unit-based services and highly trained interdisciplinary
staff delivering care to patients diagnosed with critical conditions, so too
does the highly important need of the right medication, dose and route to
initially treat, stabilize and progress patients to a healthier state.
Course Purpose
To provide advanced learning in critical care and emergency pharmacology
for clinicians working in hospital emergency and intensive care unit settings.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
2
Target Audience
Advanced Practice Registered Nurses and Registered Nurses
(Interdisciplinary Health Team Members, including Vocational Nurses and
Medical Assistants may obtain a Certificate of Completion)
Course Author & Planning Team Conflict of Interest Disclosures
Jassin M. Jouria, MD, William S. Cook, PhD, Douglas Lawrence, MA,
Susan DePasquale, MSN, FPMHNP-BC – all have no disclosures
Acknowledgement of Commercial Support
There is no commercial support for this course.
Please take time to complete a self-assessment of knowledge, on
page 4, sample questions before reading the article.
Opportunity to complete a self-assessment of knowledge learned
will be provided at the end of the course.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
3
1. Within the ICU and critical care environment, metered-dose
inhalers (MDIs) typically include medication formulations that
have been created for MDIs, such as
a.
b.
c.
d.
inhalable powder medications.
any drug available in nebulized form.
powder, liquid and water-soluble gel forms.
bronchodilator medications and corticosteroids.
2. True or False: Pharmacokinetics in critical care patients are the
only constant factors because drugs are absorbed, metabolized,
and excreted based on the drug’s composition, not the current
health status of the patient.
a. True
b. False
3. The following statement(s) is/are correct with respect to the use
of inhaled medications in the critical care environment, such as
ICU?
a. Inhaled medications are rarely used in ICU.
b. Inhaled medications are used except in patients who require
mechanical ventilation.
c. The method of administering inhaled drugs depends largely on the
patient’s ability and health status.
d. All of the above
4. _______________ is a muscarinic agonist that is used in an
inhaled preparation form to test and diagnose asthma.
a.
b.
c.
d.
Methacholine
Budesonide
Ipratropium bromide
Albuterol
5. Which of the following inhaled medications specifically act on the
beta-2 adrenergic receptors of the lungs to cause vasodilation of
the bronchioles and to improve breathing?
a.
b.
c.
d.
Ipratropium
Heparin
Methacholine
Albuterol
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
4
Introduction
Administration of medication to any patient requires careful planning,
keeping in mind the essential steps to ensuring that the correct medication
is given to promote the best outcome. Health clinicians who give medication
must follow the six rights of medication administration, including the right
patient, medication, dose, route, time, and documentation. The steps of
medication administration are even more significant in the critical care
environment, where the clinician must often think and act quickly to respond
to changes in the patient’s clinical status.
Medication Administration In The ED And ICU
Administering medication in the emergency department or the ICU adds
another element of pressure. Within critical care, clinicians may need to
administer medications quickly, without the luxury of time to check and
recheck medications. Clinicians may need to recall formulas and calculate
drug dosages quickly so that they may respond rapidly to a patient’s
changing health status. There are often many interruptions during the
course of care that could affect how medications are given. Because of the
sometimes hectic and stressful pace of critical care, there is an increased
risk of errors with medication administration.
Because the patients being cared for in the ICU often have unstable
conditions, administration of medications can lead to rapid changes. When
drugs are administered inappropriately, there is a greater chance of harm to
the patient, even if the incorrect action would be considered a minor error if
it were made outside the ICU setting. Most patients in critical care are sicker
overall when compared to their counterparts in other areas of the healthcare
facility; they often have higher numbers of comorbidities present and they
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
5
receive more medications. Critical care patients also undergo more
treatments and procedures that can induce pain or anxiety and so they may
have more prn medications to be given for comfort as well.
Pharmacokinetics in critical a care patient may be altered because of the
patient’s current health status; in other words, because critical illness can
affect how drugs are absorbed, metabolized, and excreted, patients in the
critical care environment are at higher risk of complications associated with
drug administration when their bodies cannot process the drugs
properly.45,68
There are various routes of drug administration used in critical care,
however, clinicians who work in these environments may be more likely to
administer drugs intravenously, orally, or as inhaled preparations.
Inhaled Medication
Inhaled medications are those drugs that are delivered to the lungs and that
are taken into the body while breathing in. They may be commonly
administered in the critical care environment, particularly in situations where
patients have breathing difficulties due to chronic lung disease or
bronchospasm, as well as among some patients who require mechanical
ventilation. The method of administering inhaled drugs depends on the
patient’s ability to take the medication, often as a result of the patient’s
health status. An intubated patient must be given inhaled medications
through part of the ventilator tubing. Alternatively, a patient who is not
intubated can use other mechanisms for inhaling medications, but should be
assessed for his or her ability to do so. This section covers the varied
methods of inhalation medication.47-52
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
6
For the patient who is not intubated, inhaled medications are administered
through one of several devices that make it relatively easy to breathe in the
medication and gain the effects of the drug. These devices typically include
metered-dose inhalers, dry powder inhalers, or nebulizers.
Metered-dose inhalers are some of the more common items used in the
general public to administer prescription medications for asthma or COPD
symptoms. Within the ICU and critical care environment, metered-dose
inhalers (MDIs) may also be used; their use is restricted to those medication
formulations that have been created for this specific mechanism of
administration, and typically include bronchodilator medications and
corticosteroids. The MDI consists of a canister, a propellant, and a metering
valve, all of which are contained within a plastic holder that acts as an
actuation device. The inhaler must be prepared prior to administration, so
the clinician should shake the inhaler several times before use. When
pressing on the actuator, the medication is ejected out through the
mouthpiece, the amount of which is controlled by the metering valve. The
patient who uses an inhaler must be able to briefly hold it in his mouth for
administration, and needs to coordinate breathing with the drug’s
administration. This involves breathing in at the same time the actuator is
depressed so the drug can be inhaled. The patient must hold his breath for a
few seconds after the drug is given.
Some people have difficulties with coordinating the intake of medication with
breathing in. When there is any confusion or difficulties with coordination
and the inhaler is used incorrectly, the medication can be wasted and the
patient will not receive an accurate dose, nor will he derive any benefits of
the drug. When difficulties are encountered, a spacer may be added to the
end of the inhaler to better ensure delivery of the drug. A spacer is typically
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
7
made out of plastic and is a compartment in which one end connects to the
mouthpiece of the inhaler, while the other end is placed in the patient’s
mouth. After depressing the actuator, the medication enters the spacer,
where it is held until the patient can breathe it in. With a spacer, the patient
has a little more time to inhale the medicine if he cannot coordinate his
breathing and the medication particles are not lost into the surrounding air.
A dry powder inhaler uses the same type of mechanism for delivering
medication to the patient, however with an MDI, the medicine is available in
an aerosolized form, while a dry powder inhaler uses an inhalable powder.
The dry powder inhaler also does not contain propellants that are found in
the metered-dose mechanism. This type of inhaler is often used to manage
lung conditions such as asthma or COPD, but the medications they contain
are meant for long-term control, rather than for symptomatic use.
Nebulizers are devices that transform medication that is in liquid form into
fine mist particles that can be inhaled. There are typically many more
inhaled medications that are available in nebulizer form than those that can
be given by MDI. The medication to be given through a nebulizer is available
as a prescription; the dose may already be contained within a prepackaged
unit-dose vial of liquid that contains the exact amount, although sometimes
the dose is measured from a larger container and added to the nebulizer.
Once the machine is started, a small air compressor works to change the
liquid particles into a mist. The nebulizer may have a mouthpiece in which
the patient places one end into his mouth and inhales the mist and the
medication. For some patients, a face mask, similar to those used for
administering oxygen, can be utilized as well. A patient who takes inhalation
medications through a nebulizer must be able to either hold the mouthpiece
and breathe in the mist, or tolerate having a face mask on while the drug is
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
8
being given. This often requires that the person be sitting up and be
conscious. The patient may also need to regulate his breathing so that it is
slow and steady; a rapid breathing pace can affect how much of the drug
actually makes it into the lungs.
Inhaled medications can often work very quickly after they are
administered; once the medication enters the lung, it is absorbed through
the alveoli. Because the alveoli make up such a large area of lung tissue,
absorption is often rapid and the drug is able to enter systemic circulation
after passing across the alveolar membrane. Often, there are more
difficulties with getting the medication into the lung for its absorption rather
than the process of absorption itself. An exception to this is when the patient
has chronic lung disease and the alveoli are damaged, which can
significantly limit how much medication is able to be absorbed into
circulation once it enters the lungs.
Based on the equipment available for patients to take inhaled medications,
there are many cases where some of the medication never even reaches the
patient because it is expelled into the surrounding air. The mechanisms for
providing inhaled medications must then be used correctly and the awake
patient who receives the drugs may need to be educated about how to
breathe and take the medication before giving the first dose.
Intubated patients may also receive inhaled medications when the drug is
administered through the ventilator tubing. Historically, research has shown
that many patients who receive inhaled medications, either through
nebulizer therapy or through pressurized MDIs, have often missed a majority
of the medication because of the mechanisms of administration. Studies
have shown that many patients, when given inhaled medication while on the
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
9
ventilator, only receive a fraction of the drug while the rest of the medication
is expelled into the surrounding air. However, changes in the structure of
ventilators, as well as the systems for delivering inhaled medications have
greatly improved the amount of medication that most ventilated patients are
able to receive when given inhaled drugs. A study in the Journal of Aerosol
Medicine and Pulmonary Drug Delivery shows that there are a number of
methods of administering aerosolized medications to ventilated patients
where the individual may receive up to 97.5 percent of the drug. The correct
device to use when giving inhaled drugs is based on the type of medication
being delivered, the understanding of the time it takes for the drug to take
effect, and the type of ventilator in use.
Pressurized MDIs can be used with ventilated patients to deliver inhaled
medications. When giving an inhaled drug through this method, the inhaler
is connected to a section of the ventilator circuit through an adaptor. The
actuation of the drug must be synchronized to match the patient’s
inspiration. When not synchronized to the time that the patient receives a
breath from the ventilator, a significant amount of the medication can be
lost. Use of a chamber spacer, similar to that used with a non-ventilated
patient, is often successful in ensuring that the patient with a mechanical
ventilator receives as much of the medication as possible. It is also more
successful when the inhaler is placed on an area of the circuit that is closer
to the endotracheal tube. Prior to actuating the device, the MDI must be
shaken and primed.
As with use of a MDI in a non-ventilated patient, a spacer may accompany
this method of drug administration when a ventilator is used as well.
Spacers, as discussed, are attachments connected to the inhaler that delay
the time needed to disperse the drug. Metered-dose inhalers are very easy
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
10
to use with the ventilator, however, not all drugs that are given as inhaled
products are available through this device and must be given in nebulized
form instead.
Keep in mind that heat and humidity, which are often used in the ventilator
circuit to prevent drying out of respiratory tissue and to improve mucous
clearance, may affect the amount of drug that reaches the patient’s lungs
when aerosolized medications are given. The heat and humidity may have
an effect on the size of the aerosol particles, thus impacting their delivery to
the lungs. However, it is often not possible or helpful to the patient to
remove the humidifier in order to administer an inhaled medication. The
practice of stopping the ventilator to disconnect the circuit to remove the
heat and humidity may predispose the patient to other problems that can
negate the positive effects of the inhaled drug. A drug that is given only
once in a while through the ventilator may not warrant any change in heat
and humidity, other drug preparations may need an alteration in the amount
to be given with the dosage increased. There are also some mechanisms
that may be used instead, particularly when the patient requires very
frequent doses of inhaled medications and would benefit from administration
through a dry ventilator circuit, such as with a moisture exchanger. The
benefits and disadvantages associated with administering inhaled medication
through the ventilator circuit to the intubated patient need to be realized
with each situation and changes and adaptations made accordingly.
The healthcare provider who administers inhaled medications to patients
who require mechanical ventilation must then remember that there can be
some effects of heat and humidity on the patient’s ability to receive the
largest amount of the drug, and the drug’s effects on the patient’s clinical
status should be monitored closely for signs of success. Since it is difficult to
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
11
measure exactly how much of the aerosolized drug has actually reached the
lung tissue, the caregiver must also continually assess and monitor for drug
effects to determine therapeutic outcomes.
Nebulizer therapy is another method of delivering inhaled medications to
patients who use mechanical ventilation. The delivery of the drug and the
amount of drug the patient actually receives is typically dependent on the
type and rate of nebulizer used, the position where the nebulizer is placed
on the ventilator circuit, and the type of spacer involved. Nebulizers used
with mechanical ventilation are basically divided into three different types:
jet, ultrasonic, and mesh nebulizers.
Jet nebulizers are relatively easy to use and are one of the more inexpensive
methods of inhaled medication administration in the ventilator-dependent
population. Jet nebulizers work by breaking down the liquid into particles
using compressed oxygen or air and a reservoir. The reservoir is used to
manage the size of the particles if they are too large as they are transitioned
from liquid. While easy to use, the jet nebulizer may alter the properties of
the medication.
Ultrasonic nebulizers work by creating ultrasonic vibrations that convert the
medication solution into a mist that can be inhaled. The particles created
may be slightly larger when compared to those with other types of
nebulizers but the particle size is often consistent. As with some other kinds
of nebulizers, ultrasonic nebulizers may leave some residual medication that
the patient does not receive. This type of nebulizer is not used as often
within the ICU because of its size and cost to use.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
12
The mesh nebulizer converts liquid to particles for inhalation by moving the
liquid through a fine mesh barrier. Mesh nebulizers have been shown to have
a reduced drug residual with use, which means a greater amount of the
inhaled drug reaches the patient. There is also less risk of contamination
associated with their use because the reservoir is separate from the
ventilator circuit. Mesh nebulizers are also quiet and they can be portable.
Although many inhaled medications are given to treat respiratory conditions,
there are also drugs available that can be given through the inhaled route
but that are used for the treatment of other kinds of conditions. Clearly,
bronchodilators are some of the more common drugs administered by
inhalation; however, antibiotics, including tobramycin and azithromycin, can
be administered in this method as well. Inhaled insulin (Afrezza®) is an
inhalation powder that peaks within 12 to 15 minutes of administration and
that may be beneficial for some patients with diabetes. Other examples of
some agents administered via inhalation include nebulized heparin;
corticosteroids, such as budesonide; and inhaled aerosolized prostaglandins.
Muscarinic receptors are a type of acetylcholine receptor that can be found
in the lung tissue. They are responsible for controlling and modifying smooth
muscle tone, regulating mucus production, and managing lung inflammation.
There are some drugs that act as muscarinic receptor agonists that may
cause shortness of breath if they are inhaled. For example, methacholine is
an inhaled preparation that is a muscarinic agonist that is used to test and
diagnose asthma because it can cause shortness of breath and wheezing.
The action of muscarinic receptors in the lungs may also be blocked by some
kinds of medications that are administered as inhaled drugs. When
stimulated, muscarinic receptors cause a decrease in heart rate, a decrease
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
13
in cardiac contractility, and constriction of the bronchioles. A drug that is a
parasympathetic blocker medication then blocks the action of these
muscarinic receptors and therefore causes a reverse effect. Parasympathetic
blocker medications are administered in different ways, but when used for
their effects on the bronchioles, they may be given as inhaled preparations.
An example of this is ipratropium bromide (Atrovent®), which is often used
for the management of symptoms associated with chronic obstructive
pulmonary disease. Ipratropium is given as an inhaled medication to block
the muscarinic receptors and to cause bronchodilation, which increases
airflow in the lungs and makes it easier for the patient to breathe.
Ipratropium can also decrease the amount of mucus secretions in the
patient’s lungs, which also promotes a clear airway and easier breathing. It
may cause some negative side effects associated with the respiratory
system. The most common side effects of ipratropium include respiratory
tract infection, bronchitis, cough, sinusitis, and exacerbation of COPD
symptoms. Other side effects may also include urinary tract infection,
dyspepsia, and flu-like symptoms.
Certain inhaled medications specifically act on the beta-2 adrenergic
receptors of the lungs to cause vasodilation of the bronchioles and to
improve breathing. Albuterol (Proventil®, Ventolin®) is an example of this
type of medicine. Albuterol is a bronchodilator that is primarily used for the
treatment of bronchospasm. It is administered as an inhaled medication,
often through either a nebulizer or aerosol inhaler, where it quickly works in
the lung tissue to stimulate the beta-2 receptors. Albuterol is often used as a
rescue medication and it is the first choice of treatment of bronchospasm
and has been shown through clinical trials to have a greater effect on
smooth muscle relaxation in the bronchial tissue than isoproterenol, a
sympathomimetic drug that also stimulates beta-2 receptors in the lungs, as
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
14
well as having longer-lasting effects and fewer cardiovascular effects than
isoproterenol. Because of its effects on beta receptors, albuterol may cause
some side effects, the most common include shakiness and tremor, and a
fast pulse with a feeling of pounding heartbeat that may be irregularly
paced. Albuterol may be successfully combined with other medications used
for the treatment of bronchospasm. Combivent® is an inhaled medication
that is a combination of albuterol and ipratropium, so this drug
simultaneously stimulates beta-2 receptors and blocks muscarinic receptors
to dilate the bronchioles, control wheezing, and decrease mucus secretions.
While common and often available for use in the critical care setting,
medications given through inhalers or nebulizers typically are used for their
expected purposes and may be administered as part of ongoing treatment or
in emergent, life-threatening situations. The American College of Chest
Physicians and the American College of Asthma, Allergy, and Immunology
have given guidelines about selection of the most appropriate device and
drug in different situations within the emergency department or the ICU. In
short, the executive summary that was released determined that within the
emergency department, including among cases of acute asthma and
bronchospasm, the delivery of short-acting beta-2 agonist through an MDI
or nebulizer is appropriate, based on the patient’s ability to accurately use
these devices. The use of dry powder inhalers for these same conditions is
not recommended at this point due to a lack of evidence regarding
effectiveness.
Additionally, the two medical associations have issued guidelines for the use
of short-acting beta-2 agonists administered in the inpatient hospital setting,
which state that the use of metered-dose inhalers and nebulizers, used with
spacers when needed, are both appropriate for administration of these
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
15
drugs. Among patients who are not using mechanical ventilation but who are
severely dyspneic, the use of either intermittent or continuous nebulizers to
administer medications is appropriate. Among patients who require
mechanical ventilation, nebulizers and MDIs can be used to deliver beta-2
agonist medications, keeping in mind the technical factors that can affect
delivery of these medications (for instance, the use of ventilator circuits, the
presence of heat and humidity, the inspiratory rate of the patient) as well as
the potential side effects caused by these drugs and their particular effects
on the patient (including tachycardia and premature heart beats).
Although there have been challenges with the administration of inhalation
medications to patients in critical care, particularly among those who require
mechanical ventilation, the therapeutic effects of these drugs are very
important for the patients who need them for management of lung
conditions and infections, as well as for treatment of some other symptoms
of disease. As systems of administration continue to evolve, the ability to
accurately administer these drugs and ensure that they are therapeutically
effective will continue to improve.
Intravenous Medication
Intravenous administration of medications is one of the most common routes
utilized in critical care. Many of these drugs act very quickly and produce
rapid responses because they are administered directly into systemic
circulation while bypassing the absorption stage. The rapid response of these
drugs is often necessary for this population of patients because their health
conditions may change rapidly and they may need the quick action and
effects of IV medications to combat these changes. While the rapid effects of
intravenous administration make these drugs preferable for use in critical
care, they can also expose some patients to harm if they are not carefully
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
16
and appropriately administered and the patient continually monitored with
their use.
Administration of intravenous medication requires an IV catheter; this may
be placed by emergency personnel prior to arrival at the healthcare center or
it may be started upon arrival. Typically, a patient in critical care has at least
one IV catheter in place or has a central venous catheter, which provides
fluid and medication directly into the larger vessels of the circulatory system.
The central catheter often has more than one port for administration of
different types of fluids and medications that may or may not be compatible
so that they can be given at the same time without having to wait or flush
the lines in between doses.
There are several different types of central venous catheters. Because of the
size of these lines and their ability to reach directly into central circulation,
they are often kept in place for several weeks or months at a time. They also
require a physician or specially trained advanced practice nurse to place
them. Intravenous medications may be administered through such types of
central venous catheters as peripherally-inserted central catheter (PICC)
lines, tunneled catheters, or implanted ports, as examples.
In many healthcare centers, intravenous medications arrive in the
emergency department or critical care unit prepackaged and ready for
administration from the pharmacy, however, depending on the location and
its policies, the bedside care providers often must combine and prepare IV
formulas before giving them to patients. In emergency situations, such as
when the patient needs advanced life support, the medications are available
at the bedside, whether from the crash cart or in an easily accessible
location so they can be given quickly. Intravenous medications are typically
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
17
administered either as a bolus, which may be given IV push over a very
short period, or as a short-term infusion that is given once and that is
infused through a pump or is given as a piggyback to an infusion that is
already in place.
Intravenous medications may also be administered via continuous infusion.
In this case, the fluid is prepared ahead of time in a syringe or bag; often,
the dose of the drug must be mixed with a diluent such as dextrose water or
normal saline. The infusion is administered over a period of hours, or if it is
given continuously, it is connected to the IV pump and started for an
indefinite period of time, depending on how the patient responds. For
example, the clinician caring for an individual with low blood pressure may
receive orders to start a dopamine infusion; the amount and rate is
calculated based on the patient’s weight and blood pressure. The infusion
may be set up to run continuously over a period of hours or days until it can
eventually be discontinued when the patient’s blood pressure levels are
stable. When a continuous infusion is in place for more than 24 hours, the IV
tubing and the medication container often must be changed to decrease the
risk of infection.
In most cases, intravenous infusion medications that are given through an
IV pump have the rate set and total volume computed and set by the pump,
which often eliminates the need for calculation of flow rates and drip times.
This provides a much safer method of medication administration and reduces
the risk of medication errors. However, it is still important for any clinician
who administers IV medications in critical care to have a basic understanding
of how to calculate an appropriate flow rate, in case of emergency or in
situations where a pump is not available.1,3,24,43
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
18
To calculate the IV flow rate, the nurse must know the drug concentration,
which is the amount of the drug that is available within the given solution;
and the medication dose, which is how much of the drug the patient should
get over a specified period of time. This information is written in the orders
from the provider. The concentration of the drug may vary slightly,
depending on the type of medication. For example, dopamine may be
delivered based on a calculation of micrograms/kilogram/minute, while some
antibiotics are often calculated as milligrams/kilogram/hour, especially within
pediatric populations. The nurse should be familiar with the basic units of
common drugs that are given to be able to catch any errors of concentration
if they occur. The dose of the drug should be available through the
provider’s prescription and it should specify whether the drug should be
given over a period of minutes or hours.
At times, the flow rate may need to be calculated to determine the rate in
which to set an infusion pump. Alternatively, the provider may also need to
calculate drops (gtts) per minute when IV tubing is used without a pump and
is controlled manually. It is extremely important to understand how to
calculate infusion rates and to recognize the effects that the rate of infusion
will have on a patient’s condition, particularly in the critical care setting,
where administration of some intravenous medications can cause rapid and
significant changes in the patient’s health.
To calculate the rate of infusion when a pump is available and to infuse
solution at a rate of mL/hour, the provider uses the formula:
Amount of Solution (mL) = Total mL/hour
Time in Hours
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
19
This type of calculation may be used more often with fluid administration, as
opposed to medication doses. For example, a nurse receives an order for
1000 mL D5 ½ NS to be given over 8 hours. To calculate the infusion rate,
the nurse would input the following:
1000 mL D5 ½ NS = 125 mL/hour
8 hours
To calculate gtts per minute when the flow rate will be manually controlled,
the following formula is used:
Amount of Solution (mL or mL/hr) x gtt factor = Total gtt/minute
Time in Minutes
To utilize this formula, the clinician must first know the gtt factor, which is
based on the infusion set used. The size of the drip set may range from a
mini-drip set, which has a gtt factor of 60 gtts/mL, to a regular drip set,
which has a rate of 10-20 gtts/mL. As an example, a nurse receives an order
for Ancef, with the dose in a 50 mL solution, which must be given over 30
minutes. The gtt factor is 20 gtts/mL. The nurse uses the following
calculation:
50 mL x 20 gtt = 33.3 gtts/minute
30 minutes
These examples are just two samples of possible calculations that may be
needed at the bedside of a critical care patient. Keep in mind that not all
intravenous infusions will require formulaic calculations, though; in many
cases, the drug is supplied with the information at hand and by connecting
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
20
the drug to a pump, the clinician can administer IV drugs quickly and with
relative ease. Regardless of whether IV drugs require infusion rate
calculations, the caregiver giving the drugs is always responsible for
ensuring that the patient is receiving the right drug at the correct rate.
There are a great number of intravenous drugs that are administered in
critical care. Some drugs are given continuously to maintain a patient’s state
of health when he is relatively stable; examples may include IV antibiotics,
diuretics, or opioid analgesics. Alternatively, some drugs are given
intravenously and must be administered rapidly in life-threatening
situations, including some vasopressors or antiarrhythmics. Depending on
the patient’s current state of health, the nurse may administer many IV
medications from various drug classes.
Critical care is a specialty that requires a high degree of technical knowledge
and the foresight to consider the most appropriate drugs based on the
patient’s condition and to continuously monitor response to the drug.
Intravenous medications, while fast-acting and effective, can also be very
harmful to such a vulnerable population of patients if mistakes are made.
Many patients in the ICU receive routine IV fluids, run at a continuous rate;
these fluids may be coupled with other intravenous solutions as well, such as
insulin or parenteral nutrition. When IV medications are ordered, they may
also be given in a bolus or as an added continuous solution. The provider
must then carefully check all medications for their rates of administration
and the solutions in which they will be given for compatibility and to ensure
that the patient is not getting too much. Fluid balance is an objective that
can be disrupted when IV medications are given too quickly or too slowly, or
if they are added unnecessarily to certain solutions.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
21
Further, because patients often receive many intravenous medications in this
setting, there is a greater potential for drug interactions, particularly when
several drugs are given within short periods or when using the same IV line.
Drug interactions occur when one drug changes the pharmacokinetics or
pharmacodynamics of another drug and subsequently changes its expected
effects. Drug interactions may cause antagonistic effects, in which one drug
prevents the other from exerting its effects. With these types of drug
interactions, the patient does not gain the benefits of at least one of the
drugs given or its overall intensity of effects is reduced. This could occur
accidentally, as when two drugs are administered at the same time and
cause an antagonistic effect; however, there are times when this effect is
desirable. An example is the administration of naloxone (Narcan™), which is
an antidote to opioid drugs, and can be given to counteract the effects of
these medications.
Drug interactions may also cause synergistic effects, in which the drugs
potentiate the effects of each other. When this occurs, the patient may
experience greater effects of one or both drugs, results that can be positive
or that can cause adverse effects. An example of a synergistic effect is the
combination of opioids with an antihistamine that causes drowsiness. Opioids
also can cause adverse effects of drowsiness and fatigue; giving these two
kinds of drugs together can potentiate both adverse effects and could lead to
significant changes in the patient’s condition, including stupor or loss of
consciousness.
Ideally, the clinician should be familiar with common drug interactions
associated with certain intravenous medications before administration. While
it is not possible to know all possible effects of all drugs, referencing
potential interactions and spacing the timing of drug administration, when
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
22
possible, can decrease the potential for these effects. This also includes
familiarity with each drug’s time of onset, duration, and half-life, and what
type of IV solution is compatible for administration. By utilizing reference
guides, checking with other personnel, and using medical equipment
appropriately, the clinician can safely administer intravenous medications
that will be of great benefit to the patient.
Oral Medication
Oral medications are not as commonly administered in critical care when
compared to intravenous drugs; many critically ill patients do not have the
ability to swallow oral tablets or cannot tolerate ingestion and absorption of
these drugs from the gastrointestinal tract. However, in the right
circumstances, giving medications by mouth can be one of the easiest ways
to administer drugs. There are some clinicians who believe that the oral
route of administration is not as effective when compared to IV drugs.
However, there are some medications that are only available through the
oral route and that cannot be given any other way; drugs used to treat
hyperlipidemia, such as atorvastatin, are some such examples. Further, if an
orally administered drug is able to achieve the same tissue distribution as
that of an intravenous drug, an oral medication is no less effective than the
same kind of drug given via a different route. Although the route of oral
administration requires an additional step of absorption to reach systemic
circulation, the oral preparation is not necessarily less effective than other
routes; instead, it may simply take longer to exert its effects.1,42,89
There are benefits as well as drawbacks to using oral medications in the
emergency department or the ICU. For some patients who are able to
swallow food and pills, oral medications are relatively simple to administer
and require very little preparation. They can be given on a long-term basis
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
23
and often have fewer complications associated with their use, unlike some
other routes of administration, such as problems with infection or fluid
extravasation associated with the intravenous drug route. In terms of the
different routes of medications available within healthcare, oral preparations
are some of the most economical methods. A patient who receives enteral
feedings through a nasogastric or gastrostomy tube can receive some types
of oral medications if they are crushed and administered through the tubing.
Alternatively, many patients in critical care do not have the option of taking
oral medications, as the drugs they need are not available in oral form or
they cannot take pills or tablets. Patients who are NPO (nothing by mouth)
typically do not have the option to take oral medications. Some drugs,
particularly those that are extended-release formulations, cannot be crushed
and given through feeding tubes; if a patient is then unable to swallow the
tablet by mouth, he would be unable to take the oral preparation of the
drug. Oral medications also require an additional step in the process of
pharmacokinetics in that they must be absorbed in the digestive tract before
they can be distributed and metabolized by the body.
Often, patients in critical care have health conditions that can affect drug
absorption and can distort how the body is able to distribute an oral
medication. An examination of the effects of drug administration on reducing
medication errors in critical care, found in Clinical Pharmacology: Advances
and Applications emphasized that a patient’s rapidly changing condition in
critical care often means that taking an oral medication for the treatment of
a deteriorating health condition will not work rapidly enough to produce the
desired effects; instead, an individual whose health is deteriorating quickly
often needs intravenous medications for rapid treatment.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
24
All of these factors must be taken into account when administering oral
medications in critical care. Oral medications are available in different
formulations, including those that are swallowed, such as with tablets or
capsules. They may also be placed under the tongue (sublingual) or between
the cheek and gums in the mouth (buccal) to be dissolved.
When an individual is unable to swallow oral medications, the healthcare
provider needs to make some accommodations to enable the patient to be
able to successfully take his medication. This may mean crushing the
medication, if appropriate, and mixing it in a substance that can easily be
swallowed, such as applesauce. Not all oral medications can be crushed, so
the exact order must be checked and verified before doing so. In some
cases, requesting the medication in a slightly different form may be more
appropriate. For instance, a patient may not be able to swallow an oral
medication that is in tablet form, but he may be able to swallow the
medicine if it is given as an oral syrup. The nurse often needs to assess the
patient’s current state of health and self-care abilities before administering
oral medications.
Some patients are admitted to the hospital with pre-existing conditions and
they have orders to continue to receive the same prescription drugs that
they take at home. For instance, a patient who is admitted to the hospital
for surgery and who normally takes lisinopril for hypertension at home may
eventually start taking the same medication in the hospital once his
condition has stabilized.
Some people who are given intravenous medications while in the ICU may
eventually be able to transition to taking oral medications, particularly if
they will need to be discharged to home with a prescription. This transition is
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
25
not appropriate for all patients; those who are critically ill and who cannot
tolerate oral medications should wait until they are in stable health before
making the change, for obvious reasons. When possible, patients may be
changed to oral medications for ease and cost of administration. The change
may occur over time as the patient demonstrates the ability to take oral
drugs.
In light of the potential complications associated with oral drug
administration in the ICU, caregivers must weigh decisions very carefully
about when and if a patient is able to transition to oral medications. In all
cases, oral medications must be labeled correctly and clearly; the healthcare
clinician must always witness the patient as he takes the drug, rather than
leaving the medication at the bedside for the patient to take on his own.
Splitting tablets to administer one-half of a dose is a relatively common
practice but it also increases the risk of errors. When dividing doses by
splitting tablets, the provider should note whether the drug is safe for
splitting, as noted on the packaging, and whether it is scored on the tablet.
The nurse should use a pill splitter to divide the dose, which is the most
accurate method of breaking the pill in half. Additionally, all oral drugs must
be measured carefully, particularly if in liquid form; and if a drug is an
extended-release formulation, it should be clearly noted prior to
administration and never crushed to be given through a feeding tube.
The administration of oral medications has its own benefits and challenges,
similarly to other routes of medication administration. While oral medicines
can be easy to dispense because they usually do not require mixing or
changing the drug prior to administration, it is still important to thoroughly
check every label and dose that comes from the pharmacy prior to giving the
patient an oral drug. Consideration for the time that it takes for the drug to
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
26
take effect must also be noted, as it will take longer to achieve therapeutic
effectiveness for these kinds of drugs when compared to administering
medications through other routes.
Prescription Guidelines
Within healthcare, all prescriptions, including their indications and details of
drug administration, will come from a healthcare provider such as a
physician, surgeon, or advanced practice nurse. The type of drug ordered is
based on the patient’s clinical condition and diagnosis and the prescription is
given with consideration for the drug’s effects, the time that it takes for
drugs to exert their effects, the routes that the drug can be administered,
and the overall goals for the patient’s outcomes. In some cases, drugs must
be administered very rapidly in response to the patient’s condition. As a
patient’s health status changes, drugs may be ordered in response to
maintain a stable health state. Healthcare providers who prescribe drugs
have guidance from the U.S. Food and Drug Administration, who provides
indications for drug usage and appropriate doses and administration, in
addition to information about adverse effects, use of certain drugs within
special populations, and possible drug interactions.90
The guidelines for prescribing drugs vary depending on the circumstances
under which the drug is administered and the patient’s health condition and
potential response. Within critical care, the clinician may administer many
different types of medications to control pain, calm or sedate the patient, or
manage the person’s health condition, which sometimes is done during
emergencies.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
27
Benzodiazepines
Benzodiazepines have a number of uses in medicine, with the ultimate goal
of causing relaxation, sedation, or a decrease in anxiety. Benzodiazepines
typically act as sedative-hypnotics in the central nervous system in response
to GABA receptors. Their use is primarily intended for anxiolysis, control of
insomnia, or as muscle relaxants; they may also be combined with other
drugs for their sedative effects during procedures.
Benzodiazepines are often administered to patients in critical care because of
the pain and distress that is often involved with care in these areas. Critically
ill patients often undergo painful and frightening procedures and may be
more likely to suffer from anxiety and pain as a result. Even the act of being
turned and repositioned in bed has been described by some immobile
patients as being extremely painful and difficult. Benzodiazepines combat
much of the anxiety induced in these situations by promoting calm and
reducing agitation and potential delirium associated with intensive care. This
section highlights the usefulness of benzodiazepines in the ICU and
emergency setting, as well as potential adverse effects clinicians should
know.1,11,91-93
Some of the more commonly administered benzodiazepines include
midazolam, lorazepam (Ativan®), and diazepam (Valium®). These three
drugs all act as GABA receptor agonists. Midazolam hydrochloride is a shortacting benzodiazepine that may be administered IV or as an intramuscular
injection. Because of its sedating effects, midazolam should only be used in
cases where the patient can be monitored thoroughly for hemodynamic
stability and for changes in level of consciousness. In addition to sedation,
midazolam has been associated with respiratory depression and arrest in
some patients. The drug achieves its sedating effects within three minutes
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
28
after being given intravenously; patients who receive the drug and who
become sedated may have little or no memory of the events following the
injection. One study that investigated midazolam administration during
endoscopy showed that 71 percent of people in one center had no memory
of the procedure after being given midazolam.
Midazolam has a half-life of between 3 and 11 hours, and it is eliminated via
hepatic metabolism. How much of it is actually distributed after
administration can be affected by several factors, including female gender,
advanced age, and obesity. Midazolam can be given as an initial bolus of 1
to 5 mg; as a continuous infusion, it can be administered at a rate of 1 to 5
mg/hour. Due to its effects on the central nervous system, administration of
other medications that act as depressants may potentiate the effects of
midazolam and should be avoided as much as possible. Midazolam may also
be associated with an increased risk of delirium and tolerance when
compared to some other sedative agents.
Lorazepam also acts as a central nervous system depressant in that it
causes sedation but does not necessarily impact the cardiovascular system.
Lorazepam has been shown to be beneficial in reducing anxiety, promoting
sedation, and controlling seizure activity. Within the critical care setting, it is
most typically given IV or as an IM injection. Its half-life is approximately 8
to 15 hours and its onset of action is between 5 and 20 minutes, which is
somewhat slower than some other kinds of benzodiazepines. Like
midazolam, there may be an increased risk of delirium with use of
lorazepam, and patients who have been given this drug should also be
monitored for signs of excessive sedation. Lorazepam may be administered
for the treatment of all kinds of seizures, including those due to status
epilepticus. Note that when using lorazepam for this purpose, the patient
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
29
must be closely monitored because of potential complications of the
seizures; lorazepam is just one drug that is used in seizure management in
these cases and should not be considered the definitive treatment.
Another GABA agonist benzodiazepine that may be used in critical care is
diazepam. It is available as an oral preparation, but for critically ill patients,
it is more commonly administered as an intravenous or intramuscular
injection. Diazepam is used as a mild sedative to control anxiety and stress,
particularly that which is associated with patient treatments or medical
procedures while in the hospital. It may also be used to treat seizures and
can control spasticity when neurological conditions such as cerebral palsy
are present. Diazepam has a half-life of up to 120 hours, and it is
metabolized by the liver. It is generally administered as a bolus dose and
less often as continuous drip.
As with other benzodiazepines, diazepam can cause such sedation that the
patient may experience a change in level of consciousness, drowsiness, and
amnesia of events. Its effects are potentiated with the administration of
opioids or other sedatives that also act as central nervous system
depressants. A typical dose of diazepam is 1 to 5 mg, depending on the
patient’s condition.
One contraindication that is common to most benzodiazepines is that these
drugs should not be given to anyone with a history of glaucoma. Glaucoma
is a condition in which there is increased pressure in the globe of the eye,
which leads to a loss of vision. Most people with the condition have openangle glaucoma (90 percent), which develops slowly and causes increased
pressure due to obstruction of drainage canals in the eye. Open-angle
glaucoma leaves a wide angle between the iris and the cornea. In contrast,
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
30
narrow-angle glaucoma is less common but can cause a sudden rise in
intraocular pressure from blocked drainage canals; in this type of glaucoma,
there is a narrow angle left between the iris and the cornea.
People who have narrow-angle glaucoma or untreated open-angle glaucoma
should not be given benzodiazepines, as the drugs may increase intraocular
pressure. The benzodiazepines cause pupil dilation when they exert their
effects, which can increase pressure within the eye when the angle between
the iris and cornea is very narrow. Despite the potential interactions that can
occur with use of other drugs or when some chronic medical conditions are
present, benzodiazepines can otherwise be safely administered to critically ill
patients as long as they continue to be monitored for drug safety and
effectiveness.
Propofol
Propofol (Diprivan®) is a sedative-hypnotic medication that is most
commonly used to induce anesthesia during surgery; it is also used in critical
care for sedation, such as in cases where mechanical ventilation is used or
when a patient will be undergoing an anxiety-producing or painful bedside
procedure. Propofol works as a GABA agonist to stimulate these specific
receptors, which regulates anxiety and promotes muscle
relaxation.1,25,33,44,95
The effects of propofol begin within approximately 40 seconds after it has
been administered intravenously. It has a half-life of 1 to 3 minutes, which
means that it may be administered either on a continuous basis throughout
a procedure or additional doses must be given in order to maintain its
effects. It is rapidly distributed and metabolized in the body, particularly
when it is first given. With continued administration of bolus doses or with
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
31
ongoing continuous infusion, the rate of distribution slows slightly. When
propofol is used only for a short time, such as during a relatively short
surgical procedure, the patient may emerge from anesthesia very rapidly
after the drug is discontinued. However, when propofol is used for longer
periods, some studies have shown that it takes longer for propofol to clear
the tissues, leading to longer times of emergence from anesthesia after its
discontinuation.
When giving propofol by repeat bolus injection, the provider should
continually assess the patient’s hemodynamic and clinical status as a
response to the previous injection before giving the next so that the dosage
can be adjusted if necessary. When given for surgical induction, a typical
dosing range in adults is 2 to 2.5 mg/kg, or about 40 mg given every 10
seconds. For continuous IV sedation in the intensive care unit, propofol may
be given at a rate of 0.3 mg/kg/hr, increasing every 5 to 10 minutes by 0.3
mg/kg until reaching the desired amount of sedation. The actual rate and
dose of propofol can vary based on the specific condition of the patient.
Propofol can have a significant impact on the cardiovascular and respiratory
systems. Patients who receive propofol can be at risk of decreased oxygen
saturations, increased carbon dioxide levels, and hypotension, which may
occur before an overall decrease in cardiac output. These effects are
aggravated further when propofol is given with another drug that affects
hemodynamics, such as with analgesic drugs. Propofol can cause respiratory
depression and patients who are given the drug often require assisted
ventilation, as its administration may lead to apnea.
As previously discussed, moderate sedation involves the administration of
sedatives during some procedures to keep patients comfortable. Propofol
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
32
may be used as part of moderate sedation to induce amnesia of the event
and to reduce patient anxiety or movement during the procedure. Recall that
with moderate sedation, the patient has a depressed level of consciousness.
The American Society of Anesthesiologists recommends that even though
propofol may be used for moderate sedation, any patient who receives
propofol should be monitored as if he were receiving deep sedation. When
deep sedation is used, such as during general surgery, the patient is
monitored very closely and an anesthesiologist ensures the proper balance
of anesthetic and sedative medications and provides intubation to assist the
patient with breathing. Even though moderate sedation does not induce such
effects, the use of propofol may increase the risk of apnea and loss of
consciousness such that the provider should be able to respond as if the
process were actually involving deep sedation.
Any person who administers propofol should have the training to provide
resuscitation for the patient who inadvertently enters a deeper state of
sedation than originally intended. This includes an understanding of the
purposes, proper dose, and potential complications associated with propofol,
the ability to perform advanced cardiac life support procedures, if required;
the ability to provide adequate airway management; and the understanding
of early signs of possible complications of propofol, including bradycardia,
hypoventilation, and decreased oxygen saturations. This includes the
immediate availability of hemodynamic monitoring equipment, oxygen
delivery equipment, and tools to provide an airway and ventilation. The
healthcare provider who administers propofol must also have a thorough
understanding of the appropriate elements for monitoring patient sedation
and should be available immediately for assistance, if needed.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
33
Another element that must be considered with propofol administration is its
lipophilic tendencies, in that it has the potential to accumulate in the adipose
tissue of the patient, particularly when it is administered over a longer
period of time. A drug is said to be lipophilic when it is capable of being
dissolved in or absorbed into fatty tissues. When propofol is administered
over time, if it is absorbed more into the patient’s adipose tissue, the drug
may exert unstable effects that can make it dangerous to use; this is
especially important when considering the longer term use of propofol in the
morbidly obese patient who has a larger amount of adipose tissue. Even
when the drug is discontinued, it may continue to exert effects over time to
the detriment of the patient. In order to prevent this effect, the
administration of propofol, particularly during surgery, should be controlled
and kept to shorter periods and administration of other drugs that would
exert the same effect but that do not accumulate in fat tissue should be
considered instead. An example might be replacing propofol with another
drug such as remifentanil or ketamine that are not necessarily stored in
adipose tissue and that may exert more stable effects.
Propofol infusion syndrome (PRIS) is a potentially life-threatening condition
that can develop with propofol use. It occurs when a patient develops
profound bradycardia that progresses to asystole in addition to one of four
related conditions: metabolic acidosis, rhabdomyolysis, hyperlipidemia, or
enlarged or fatty liver. According to an article by Loh, et al., in the journal
Continuing Education in Anaesthesia, Critical Care & Pain, the occurrence of
PRIS is not necessarily related to the dose or rate of propofol, but it may
more commonly occur with continuous infusion, such as when providing
ongoing sedation in the ICU.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
34
Patients who develop PRIS are more likely to have neurological injuries, to
have simultaneous infusions of either corticosteroids or catecholamines, and
may be younger in age. It may present as metabolic acidosis as a result of
lactic acidosis and poor renal function. The patient often develops ECG
changes suggestive of cardiac instability, including ST-segment elevations.
Other cardiac arrhythmias may also be present. There are increased levels of
lipids in the bloodstream as well as increased serum creatine kinase and
myoglobin from skeletal muscle tissue breakdown. The management of PRIS
involves continual monitoring of the patient’s condition, including laboratory
levels of triglycerides, creatine kinase, and tests of kidney function, as well
as cardiovascular changes noted with hemodynamic monitoring. The
propofol should be discontinued as soon as PRIS is suspected and the drug
replaced with another sedative agent.96 Unfortunately, PRIS can be very
difficult to treat once it develops, which further supports the idea that
propofol use must be done very carefully. Although the drug is very active
and successful at inducing sedation and memory loss of potentially traumatic
procedures, it is always used with caution.
Butyrophenones
Butyrophenones are a type of antipsychotic medication that may be
administered for the management of various conditions, including acute
psychosis or confusion. These drugs may also be referred to as neuroleptic
medications or major tranquilizers. The two most common types of
butyrophenones administered in critical care within the United States are
haloperidol (Haldol®) and droperidol (Dridol®).1,11,97-101
There is greater potential for development of delirium within the intensive
care environment; some sources state that delirium in this patient
population can vary between 20 and 80 percent. The patient who develops
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
35
delirium typically exhibits a change in mental status, confusion, and memory
loss that could cause agitation and aggression. The individual may have a
depressed level of consciousness as well. Delirium is thought to develop in
this population due to a variety of factors, including an alteration in oxygen
levels to the brain, particularly following times of decreased oxygenation, the
presence of infection or sepsis, severe pain from procedures or surgery, as a
symptom of acute or chronic illness, or with concomitant administration of
certain medications, including some analgesics and benzodiazepines.
Unfortunately, despite the prevalence of delirium within critical care, the
condition is often not recognized until the patient has suffered from its
negative effects. Delirium is associated with an increased length of stay in
the hospital, increased time needed for mechanical ventilation, and overall
increased patient mortality.
Butyrophenones may be given to patients who have developed delirium and
who are suffering because they cannot think clearly, they have altered
mental status, or they suffer from hallucinations. The administration of these
kinds of antipsychotics can help patients overcome many of these symptoms
and may be calming during this potentially frightening time.
Additionally, some patients who are cared for in the ICU have dementia,
which although different from ICU-related delirium, can still cause profound
difficulties with thought control, memory, and problems with sleep.
Dementia is permanent and develops slowly over time, as opposed to
delirium, which can develop quickly with hospitalization. Some patients with
dementia are at greater risk of developing delirium, as well.
Haloperidol is a major antipsychotic often used for the management of
schizophrenia. It exerts its effects by blocking dopamine receptors to relieve
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
36
hallucinations, confusion, and delusions. Historically, haloperidol has been a
first choice of treatment of ICU delirium, however, it does carry an increased
risk of adverse effects, some of which could be life-threatening. Some
patients who have been given haloperidol have suffered from severe cardiac
effects, including sudden death, QT prolongation, and torsades de pointes.
Additionally, use of some antipsychotics such as haloperidol may lead to an
increase in overall mortality among elderly patients with dementia-related
psychosis.
Studies regarding the use of haloperidol for management of delirium in ICU
patients have been conflicting. A 2013 study in The Lancet looked at
whether treatment with haloperidol would decrease the amount of time that
critically ill patients would spend in delirium and found that administration of
haloperidol did not necessarily decrease the length of delirium in studied
patients. Alternatively, a 2014 review by Reade, et al., in The New England
Journal of Medicine reported on studies that considered prophylactic
haloperidol and determined that its administration prior to surgery reduced
the severity and duration of delirium and that low-dose haloperidol
decreased delirium during anesthesia induction. The research regarding the
safety and effectiveness of haloperidol will continue and some experts advise
to use other forms of antipsychotics for ICU delirium instead.
Droperidol is another example of a butyrophenone medication. It is given as
an injection and has been approved for the management of nausea and
vomiting associated with surgery. It also has a marked tranquilizing effect
and acts as a sedative, which can be calming to the anxious or distressed
patient. A person who receives droperidol is more likely to feel relaxed and
tranquil but does not necessarily experience a change in level of
consciousness. Droperidol acts as an alpha-adrenergic antagonist and may
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
37
cause vasodilation, which can work against some of the effects of
vasopressors.
In a manner similar to haloperidol, droperidol can also cause negative
cardiac effects, including QT prolongation and torsades de pointes, which
could lead to sudden cardiac death. It should therefore never be given to a
patient with a history of cardiac ECG abnormalities, particularly with QT
abnormalities. It can be given intravenously or as an intramuscular injection;
a typical single dose for an adult patient is 2.5 mg IV or 5 mg IM.
Whether a person is exhibiting an altered mental status related to his
medical condition or if he is suffering from acute psychosis, the
administration of neuroleptic medications can be helpful in controlling
symptoms. Although some of the safety factors associated with
butyrophenones have been called into question, there are many cases where
these types of drugs are appropriate and their use is warranted. As with
administration of other kinds of medications in the critical care setting,
continued monitoring for side effects and therapeutic outcomes when giving
these drugs is essential to maintain patient safety and comfort.
Opioids
Opioid analgesics are commonly administered for pain control in the ICU as
well as in the emergency department. Pain is frequently associated with the
injuries and illnesses that require critical care; often, the pain is so intense
that the affected patient requires rapid but ongoing relief. Opioid drugs are
designed to manage the moderate to severe pain that often develops within
this population. Many patients in these areas are also subjected to painful
procedures that require opioid analgesia prior to start and after treatment is
complete. There are any number of procedures that are painful for the
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
38
patient, including wound care and dressing changes, placement of drains
and tubes, suctioning of endotracheal tubes, or placement of central venous
catheters. The American College of Critical Care Medicine recommends preemptive and prophylactic analgesia prior to painful procedures to alleviate
pain in the ICU patient, including the administration of opioid
analgesics.1,26,102
Opioid analgesics are the first-line drug of choice to treat non-neuropathic
pain in critically ill adult patients. The type of opioid drug administered
depends on the patient’s current medical condition. Since certain opioids
may be metabolized and excreted in slightly different manners, one patient
may tolerate the effects of a specific type of opioid, but another person in
the same unit who is also experiencing pain may have a condition that would
negatively affect the distribution or metabolism of the same drug.
Additionally, drug doses of opioids are often prescribed with a range in mind,
depending on the amount of pain the patient is experiencing and the extent
of relief gained from the particular kind of drug.
Within critical care, most opioids are given intravenously since this method
eliminates the step of drug absorption and the drug is already given into
systemic circulation. The patient can then achieve pain relief much more
quickly than when given the drug through an oral or intramuscular route.
Further, many patients in the ICU have altered gastrointestinal functioning:
they may require enteral feedings through a nasogastric tube, they are NPO
because of a treatment, or they may be so ill that they are unable to eat at
all. In these cases, it is impractical to administer oral opioid analgesics and
these patients would obviously require intravenous administration.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
39
As discussed, healthcare providers who care for patients in the critical care
environment must be aware of any procedures that might induce pain as
well as whether the patient is experiencing pain due to his overall condition.
Frequent monitoring before, during, and after treatments is essential for
providing pain control.
Morphine is one of the most commonly administered opioid analgesics in
critical care; it is frequently given for control of acute pain in the emergency
department, as well as for pain due to procedures such as surgery or
bedside treatments given in the ICU. It is classified as a Schedule II
narcotic, and morphine has been shown to be effective in managing
moderate to severe pain. It can be given safely with few side effects when
monitored appropriately. Within critical care, morphine is almost always
administered intravenously. For some patients who are conscious and alert,
morphine delivery through patient-controlled analgesia (PCA) is a viable
option for pain control over a period of hours or days of receiving care.
When given intravenously, morphine has a rapid onset of action and it exerts
its effects within approximately 20 minutes of administration. Its duration of
action may last 4 to 5 hours. It is widely distributed and is metabolized by
the liver. It has a half-life of approximately 2 to 4 hours in adults, but this
amount is shorter in children. The actual dosing guidelines for morphine can
vary widely; because morphine is also frequently given for control of pain
associated with cancer, its chronic use may sometimes require very large
doses for those patients. For non-cancer pain, adult patients may receive
anywhere from 4 to 15 mg IV of morphine every 3 to 4 hours, based on pain
intensity. For continuous infusion, morphine is often administered at a rate
of 0.8 to 1 mg/hour, which may be given after an initial bolus dose.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
40
The most common side effects of morphine involve changes in central
nervous system functioning; for a patient who is normally alert, this may
mean an altered level of consciousness, dizziness, sedation, or even
hallucinations. Morphine can also affect the nerve supply to the
gastrointestinal tract, leading to constipation, nausea, and vomiting. Other
side effects and complications of morphine include hypotension, bradycardia,
blurred vision, and respiratory depression, which can be life threatening if
not recognized quickly and promptly treated.
Fentanyl is another kind of opioid analgesic commonly administered to
patients in the emergency room and in the ICU for moderate or severe pain.
Fentanyl may be administered through various routes, including intravenous,
transdermal, and epidural methods, but it is often effectively administered
as an intravenous preparation. As with morphine, fentanyl may be given
through PCA for some patients. When given as an intravenous injection, it
may be called by its brand name, Sublimaze®.
Fentanyl has very powerful analgesic effects; it is said that a 0.1 mg dose of
fentanyl is equivalent to 10 mg of morphine. Additionally, fentanyl does not
produce histamine, which is a relatively common effect of some other opioid
analgesics. Because of this, fentanyl is less likely to cause itching or
hemodynamic instability. Fentanyl is also less likely to cause respiratory
depression when compared to morphine, but because it is an opioid
analgesic, it could lead to a slowed breathing rate. Patients who are given
fentanyl may also experience bradycardia, dizziness, muscle stiffness,
somnolence, and possible chest discomfort.
In addition to morphine and fentanyl, there are various other kinds of opioid
analgesics that may be used to successfully control patient pain in the ICU or
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
41
the emergency department. Most opioids, when titrated to effectiveness for
each patient’s condition, are equally effective at controlling moderate to
severe pain. Other examples of opioid analgesics that may be considered for
use in critically ill patients include hydromorphone, methadone, and
remifentanil hydrochloride (Ultiva®). Note that the administration of
meperidine is not recommended in critically ill patients because of its risks of
causing neurotoxicity.
The administration of analgesic medications should not be limited to painproducing procedures. Although patients in the ICU commonly experience
pain because of undergoing certain medical treatments, these patients also
often experience pain at rest. All patients in critical care should be frequently
assessed for pain while at rest in addition to pain associated with treatment
measures. Based on the continual assessment and evaluation of pain, the
appropriate dose of analgesia can be determined.
Non-opioids
Non-opioid analgesics are administered for treatment of mild-to-moderate
pain and they may be given as adjuvants to opioids or other GABA analog
drugs to decrease some of the adverse effects that may be associated with
opioids. Non-opioid analgesics have slightly different mechanisms of action,
depending on the drug used. Although they often can be used without a
prescription, non-opioid analgesics may still cause adverse effects that can
be significant. They can be administered orally as tablets or capsules, but
within critical care, they are more likely to be given as intravenous
preparations. Some of the more common non-opioid analgesics include
acetaminophen, ibuprofen, and ketorolac.1,102
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
42
As discussed, acetaminophen is a mild pain reliever that has anti-pyretic
qualities as well. Unlike NSAIDs, acetaminophen does not necessarily relieve
inflammation. Its exact mechanism of action is not well understood.
Historically, acetaminophen has only been given as an enteral or rectal dose,
but in 2010, an intravenous preparation (Ofirmev®) was approved for use.
Intravenous acetaminophen is given for moderate pain and is used as an
adjunct to opioid medications. Its use may also decrease some of the need
for larger amounts of opioids. The drug has a half-life of 2 hours and it
exerts its effects within 5 to 10 minutes of administration. The appropriate
dose of acetaminophen is 1000 mg, given every 4 to 6 hours, but not to
exceed 4 g in 24 hours total.
One of the more common types of NSAIDs, ibuprofen is a non-opioid
analgesic that is useful for controlling mild-to-moderate pain and
inflammation. As with acetaminophen, ibuprofen can be given as an adjunct
to opioid analgesics to reduce opioid use and side effects. Ibuprofen has also
been traditionally given as an oral preparation, but it is available in IV form
as well. The FDA approved it for IV use in 2009.
Ibuprofen is a non-selective COX inhibitor, which means that it inhibits both
COX-1 and COX-2 enzymes that are responsible for creation of
prostaglandins that contribute to pain. In addition to its control of pain and
inflammation, ibuprofen may also act as a fever reducer. It can cause
damage to the gastrointestinal tract, including development of ulcers and
bleeding, and so should be used with caution in any patient with a history of
gastrointestinal disease, as well as anyone with bleeding tendencies.
Ibuprofen IV is administered as 400 to 800 mg every 6 hours and the dose
is infused over a period of at least 30 minutes. A patient should not receive
more than 3.2 g in 24 hours.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
43
Ketorolac (Toradol®) is also used for treatment of moderate pain. As with
ibuprofen, ketorolac is an NSAID that also acts as a non-selective COX
inhibitor to control pain and inflammation. It may be administered as an IV
or intramuscular injection. Ketorolac has a half-life of up to 8 hours and a
time of onset within 10 minutes of administration. It can be given as 30 to
60 mg once every 6 hours, and it should not be used for more than 5 days
at a time.
Because pain involves so many factors, the combination of non-opioid pain
medications with opioid analgesics is often very effective in reducing pain in
most patients and promoting comfort. Non-opioid analgesics, because they
are less powerful than opioids, should not be used as the sole analgesic for
pain control in patients, particularly those recovering from surgery or those
undergoing painful medical procedures. However, when an individual is
suffering from mild or moderate pain, non-opioid drugs may be used.
Further, they are particularly helpful when interspersed with opioids on a
rotating basis. For instance, a patient recovering from surgery may have
severe pain and may be given an opioid analgesic, followed by a non-opioid
analgesic shortly thereafter to maintain a state of comfort. Eventually, the
person may be able to transition from intensive opioid use to non-opioids.
Despite their lack of narcotic activity, non-opioid drugs are very valuable
components when handling patient pain.
Dopamine
Dopamine hydrochloride is a vasopressor medication most commonly
administered for the control of blood pressure and prevention of
hypotension. A common brand name of dopamine is Intropin®.1,23
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
44
Dopamine is normally produced within the body as a neurotransmitter that
works to improve cardiac function by increasing cardiac contractility and
increasing heart rate and it improves blood flow to the tissues. Dopamine
hydrochloride is a synthetic version of the neurotransmitter; it is formed
from the amino acid L-DOPA and is a precursor to the neurotransmitter
norepinephrine.
Dopamine may be administered for any condition in which a patient has
severe cardiac compromise; common situations may include severe injuries
associated with trauma; heart failure or kidney failure, following cardiac
surgery, or in cases of myocardial infarction. Dopamine is sometimes
administered to newborn, premature infants with cardiac instability when a
congenital heart defect is present.
Dopamine is given as an intravenous injection via continuous infusion; it is
typically not given as a bolus or intermittent infusion. It is available as a
powder that must be diluted prior to use, however, in many facilities that
have pharmacies that prepare IV medications, dopamine may be available to
bedside clinicians already diluted and ready for administration. It has an
approximate half-life of 2 minutes. Once given, dopamine acts as an agonist
on dopaminergic receptors to exert its effects. It is metabolized by the liver
and kidneys and is excreted in the urine.
The amount of dopamine ordered varies slightly depending on the reasons
for its administration. Typically, a dose ranges between 1 and 5
mcg/kg/minute, given by a continuous intravenous infusion, but the usual
adult dose can be between 0.5 and 12 mcg/kg/minute, depending on
severity of the patient’s condition. The amount may be titrated based on the
patient’s response. A person who has continuous hemodynamic monitoring
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
45
may need dopamine titration based on his blood pressure values. The rate of
dopamine administration can be increased or decreased as the blood
pressure values fluctuate until he reaches a stable level.
Because dopamine is given at a specific rate per kg per minute, the
healthcare provider must first obtain an accurate patient weight and convert
it to kilograms. The rate per kg per minute requires careful calculation for
accurate therapeutic administration. As an example, a patient who weighs
220 lb. has an order for 8 mcg/kg/minute of dopamine. The drug is available
as 800 mg in a 500 mL bag of D5W. This would be calculated as:
8 mcg x 99.8 kg (220 lb.) x 60 = 47.9 mg/hr
1000
47.9 mg x 500 mL = 29.9 mL/hr
800 mg
This amount can then be recalculated as needed to increase or decrease the
rate of the infusion, based on the patient’s response.
Side effects of dopamine may be related to its effects on vasoconstriction
and increased cardiac contractility, including tachycardia and palpitations,
angina, atrial fibrillation, and ectopic heartbeats. Additionally, dopamine
hydrochloride can cause side effects of nausea, vomiting, headache, anxiety,
and dyspnea.
A patient who has hypovolemia due to blood loss will require other measures
of support to correct volume depletion before dopamine can be effective. In
other words, with excess volume loss, dopamine’s effects of vasoconstriction
will not correct blood pressure enough to prevent shock. The patient must
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
46
first receive circulatory support through infusion of colloids or crystalloid
solutions before being given dopamine.
There are some cases where dopamine should not be given because of its
interactions with other drugs or substances. Patients with
pheochromocytoma, which is a tumor that develops on the adrenal gland,
should not receive dopamine because the pheochromocytoma tumor
secretes excess catecholamines, including epinephrine and norepinephrine.
Dopamine is also a catecholamine, and the excess release of these
substances could lead to organ damage. Additionally, dopamine has been
shown to interact poorly when given to those who already take monoamine
oxidase inhibitors (MAOIs), because of their effects on neurotransmitters in
the brain. Consequently, any patient who already takes MAOIs should
receive a reduced starting dose of dopamine, approximately 1/10th of a
normal dose given.
Because of its effects on the cardiovascular system, dopamine requires
continuous hemodynamic monitoring throughout its use to determine
fluctuations in patient blood pressure. The patient’s clinical status must also
be monitored, as with use of any type of pressor. Since dopamine is typically
given when a patient is already quite ill to begin with, routine monitoring
and close supervision will most likely already be in place.
Dobutamine
Dobutamine (Dobutrex®) is primarily used in cases of decreased cardiac
output and low blood pressure, particularly in states of cardiogenic shock.
Dobutamine is an inotropic agent that is designed to improve heart muscle
function. It stimulates the beta receptors of the heart to cause an increase in
heart rate and cardiac contractility. Dobutamine actually has an affinity for
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
47
both beta-1 and beta-2 receptors; when stimulating the beta-1 receptors, it
acts as an inotrope and when stimulating beta-2 receptors, it can promote
mild vasodilation. The drug is meant to only be used as a short-term
preparation.1,23,23,103
A standard dose of dobutamine ranges from 2.5 to 10 mcg/kg/minute; as
with dopamine, dobutamine is almost always given as a continuous
intravenous infusion and not as an intermittent bolus. Once administered, its
onset of action is within two minutes, leading to a fairly rapid response. It
may be titrated based on patient response and by parameters ordered by
the physician. For example, a patient’s dose of dobutamine may be
increased as needed every 15 to 20 minutes by 2 mcg/kg/minute based on
the receiving patient’s blood pressure response.
In cases of decreased cardiac function because of shock, the patient may
exhibit poor perfusion and decreased oxygenation because of poor cardiac
output, which can greatly increase overall mortality. Administration of
dobutamine for treatment of shock can increase blood flow through
increased cardiac output and can promote tissue oxygenation. It has a halflife of 2 minutes.
As with dopamine, dobutamine given in the presence of hypovolemia cannot
be expected to correct low volume. When cardiac arrhythmias, including
atrial fibrillation, are present, the patient requires an antiarrhythmic agent
such as digoxin prior to receiving dobutamine; the arrhythmia should be
treated first to prevent a deleterious response.
Dobutamine causes side effects related to its effects on the cardiovascular
system, including angina, ectopic heartbeats, an increase in atrioventricular
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
48
conduction, and tachycardia. It may also lead to an increase or decrease in
blood pressure. Other adverse effects often seen with dobutamine include
nausea, vomiting, paresthesia, dyspnea, and leg cramps.24 Although
dobutamine causes initial vasodilation, some patients may experience such
an increase in heart rate that systolic blood pressure levels may also greatly
increase, requiring a dose reduction. The routine and continuous monitoring
of patient hemodynamic status is essential with administration of
dobutamine to prevent complications of cardiac arrhythmias, tachycardia,
and hypertension.
Isoproterenol
Isoproterenol (Isuprel®) is an inotropic sympathomimetic drug used for the
management of certain cardiovascular conditions, including myocardial
infarction, hypotension leading to shock, heart failure, and certain cardiac
arrhythmias. Isoproterenol works by stimulating the beta-1 receptors in the
heart and the beta-2 adrenergic receptors found in the lungs and in the
arteries of the skeletal muscles.1,34,35,38,113
Stimulation of the beta-1 receptors causes an increase in cardiac
contractility, thereby improving the heart rate and the strength of the
heart’s contractions. Beta-2 receptor stimulation dilates the size of the
bronchioles, which improves respiratory rate by increasing air flow. The
arteries of the skeletal muscles are also dilated, which increases blood flow
to the muscles.
Isoproterenol has an almost immediate onset of action when it is
administered intravenously. It has a half-life of 2.5 to 5 minutes and its
effects can last almost 15 minutes. Because of this, isoproterenol may need
to be given as a repeat bolus dose or as a continuous infusion, depending on
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
49
the reasons for its use. It is rapidly distributed through the bloodstream
following administration, metabolized at various locations in the body but
primarily in the liver, and excreted through the urine.
Side effects associated with isoproterenol include tachycardia, palpitations,
diaphoresis, cardiac arrhythmias, tremor, and pulmonary edema. The
increase in cardiac contractility leads to an increase in oxygen consumption
and the patient may experience angina. Additionally, some people
experience increased feelings of anxiety, restlessness, nervousness,
headache, and dizziness.
Within critical care, isoproterenol is primarily used in cases of cardiovascular
compromise to support the patient’s hemodynamic system and improve
blood flow. This is often during emergency cases or very critical situations in
which the patient is suffering from a life-threatening condition. According to
the manufacturer’s guidelines, isoproterenol is indicated in cases where
shock or pacing is either not necessary or is not yet available, such as in
cases of heart block, bradycardia, myocardial infarction and cardiac arrest;
and for cases of bronchospasm that can develop during surgery and with
mechanical ventilation.
Because isoproterenol has significant effects on the cardiovascular system, it
is also used in off-label methods with some success. Isoproterenol has
effectively been used in some cases where other cardiac medications have
not been successful in increasing cardiac contractility, in episodes of
ventricular arrhythmias, or in patients receiving treatment for overdose of
beta-blocker medications. Formerly, isoproterenol was administered as part
of the algorithm of advanced cardiac life support (ACLS), but it is no longer
considered to be a first-line treatment. Instead, isoproterenol should only be
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
50
administered after atropine, dopamine, and epinephrine if pacing is not
available. It is never given to pediatric patients as part of advance life
support procedures for cardiac arrest; it is only given for episodes of
bronchospasm associated with status asthmaticus in this population.
Isoproterenol is almost always administered as a continuous infusion and
very rarely as a bolus dose, except in certain cases of off-label use, such as
with rare, inherited conditions that cause cardiac arrhythmias. Even in these
cases, isoproterenol is administered with a bolus dose followed by infusion.
For most adults, the usual dose range is 0.1 to 1.5 mcg/kg/minute. Any
patient that receives isoproterenol should be closely monitored for side
effects of vasodilation, including the effects of hypotension.
Isoproterenol has been implicated as possibly being responsible for the
development of life-threatening cardiac arrhythmias, which further supports
its need for frequent monitoring with use and discontinuation as soon as
feasibly possible. A case study in The Journal of Innovations in Cardiac
Rhythm Management discussed a situation where a female patient was
admitted for treatment of narrow-complex tachycardia. She underwent
electrophysiology studies to determine the source of the tachyarrhythmia
and received an infusion of isoproterenol during the procedure, which lasted
approximately 90 minutes. Following electrophysiology, she developed
severe hypotension that progressed into pulseless electrical arrest and which
required CPR. The healthcare team was able to resuscitate the patient and
her initial hemodynamic studies showed damage consistent with stressinduced cardiomyopathy, a condition in which the left ventricle becomes
enlarged, yet there is not evidence of an obstruction in the coronary
arteries. The condition is sometimes called “broken heart syndrome.” The
patient recovered from the cardiomyopathy after several weeks, but the
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
51
case study authors postulated that the condition developed because of the
infusion of isoproterenol. Their theory is that the isoproterenol caused the
cardiomyopathy because of its potential for cardiac arrhythmias and that a
prolonged infusion in this case led to the release of more catecholamines
that contributed to the left ventricular damage. Further studies are needed
to determine whether isoproterenol infusions can have this direct effect;
additionally, the case study itself remained a hypothesis of the negative
effects of isoproterenol, rather than a clinically proven causative factor in the
cardiomyopathy.
Due to its effects on the cardiovascular system, in particular the vasodilation
of the blood vessels, isoproterenol should not be administered with other
drugs with vasodilatory effects, such as dopamine. Because cardiac
arrhythmia is one of the major side effects associated with isoproterenol, the
patient who receives this drug should be placed on hemodynamic monitoring
during administration, including continuous ECG, blood pressure, and heart
rate monitoring, with care observation and assessment for any changes in
cardiac rhythms.
Phosphodiesterase Inhibitors
Phosphodiesterase (PDE) inhibitors are drugs that work by blocking the
effects of phosphodiesterase, an enzyme that contributes to various
functions within the body. The PDE inhibitors are classified into different
groups that range from PDE1 to PDE12. The PDE3 and PDE5 inhibitors are
the most commonly administered drugs within critical care. PDE3 inhibitors
are given to strengthen the intensity of cardiac contractions by decreasing
preload and afterload, thereby increasing cardiac output. They are most
often used for heart failure, particularly in cases that are otherwise
unresponsive to other treatments.1,104-106
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
52
The drugs are thought to work by increasing the movement and storage of
calcium in the cardiac cells. One of the more commonly administered PDE
inhibitors that may be used in critical care is milrinone. Cilostazol, another
PDE3 inhibitor, may be administered for some patients who suffer from
intermittent claudication as a result of peripheral artery disease.
Milrinone is an inotropic agent in that it strengthens the heart muscle; it also
acts as a vasodilator to improve blood flow. Cyclic adenosine
monophosphate (cAMP) is a signaling molecule, called a second messenger,
that triggers physiological cell changes and that plays a role in metabolism
and regulation of hormones. Milrinone acts as a selective inhibitor for cAMP
phosphodiesterase enzymes in the heart and the smooth muscles of the
blood vessels. This action impacts the movement of calcium into the cell and
increases the force of the cardiac contraction. Milrinone can also increase left
ventricular pressure and cause a vasodilatory effect.
Milrinone is administered by IV infusion; it may take effect within 15 minutes
of administration. For patients with heart failure, milrinone leads to
decreased vascular resistance, decreased capillary wedge pressure, and
slightly increased heart rate. The administration may then increase urine
output in this population and if a patient with heart failure also has a
prescribed diuretic, the dose may need to be adjusted.
Milrinone has also been shown to improve symptoms of pulmonary
hypertension in patients with heart failure. An article in the Annals of the
American Thoracic Society stated that milrinone is often a first choice of
medication among patients in this population. Although milrinone acts as an
inotropic agent, it has less effect on the cardiac conduction system and will
not increase cardiac output so much as to affect pulmonary artery pressures.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
53
The PDE5 inhibitors are most commonly known for their effects on
circulation for the treatment of erectile dysfunction; an example of one of
these drugs is sildenafil (Viagra®). However, they may also be implemented
for treatment of some patients with pulmonary hypertension, which occurs
as an increase in pulmonary artery pressure that leads to increased vascular
resistance and ultimately, heart failure. Pulmonary hypertension can cause a
decrease in PDE5, also known as cyclic guanosine monophosphate (cGMP)
phosphodiesterase type 5, as well as a decrease in the production of nitric
oxide, which acts as a vasodilator. PDE5 is produced in the lungs and breaks
down cGMP, which is normally responsible for keeping the blood vessels
dilated. Inhibition of PDE5 then produces an opposite effect and allows
vasodilation. The effects of sildenafil can be used to increase blood flow to
correct erectile dysfunction, but the same effects improve vasodilation in the
pulmonary vasculature to manage pulmonary hypertension. When
administered for the latter purpose, it is marketed under the brand name
Revatio®.
Revatio may be given as an oral medication or as an IV injection. When
administered intravenously, the dose is 2.5 to 10 mg three times per day,
given every 4 to 6 hours. The drug has a half-life of approximately 4 hours.
Patients who have been given Revatio have been shown to achieve a
significant reduction in pulmonary artery pressures after administration.
There are different types of pulmonary hypertension that are classified by
the World Health Organization, so research into the effectiveness of different
PDE inhibitors is an ongoing process. The continued use of both PDE3 and
PDE5 inhibitors may provide prospective treatment for other forms of cardiac
disease and hypertensive states in critical care patients in the future.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
54
Epinephrine
Epinephrine is a natural substance in the body that has several actions,
including that of a hormone and a neurotransmitter. Epinephrine is normally
created from norepinephrine within a specific area of the kidneys. It works
by increasing blood flow to the tissues and improving cardiac output.1,41,85-88
When given as a medication, epinephrine binds to alpha-1 adrenergic
receptors found in the blood vessels. This binding effect causes
vasoconstriction, which improves blood pressure and can relieve
hypotension. A patient with such hypotension as to affect blood flow and
oxygen to the critical organs may respond to epinephrine administration,
thus restoring adequate blood flow. Binding of epinephrine to the alpha-1
adrenergic receptors also improves cardiac output, further increasing
circulation of oxygenated blood. The increased cardiac output is manifested
as an increase in cardiac contractility (an improvement in the force of the
heart’s contractions), as well as an increase in heart rate and improved
conduction of the heart’s electrical system through the atrioventricular node,
which stimulates the heart to contract.
Epinephrine is also a beta-1 and beta-2 receptor agonist in that it stimulates
the beta receptors in the heart, which also promotes cardiac contractility. It
stimulates the beta-2 receptors in the lungs and in the skeletal muscles,
which increases blood flow to these sites, thereby improving breathing
mechanisms and skeletal muscle movement.
Epinephrine is one of the main drugs given during ACLS; it is particularly
effective for the treatment of situations in which the patient has suffered
cardiac arrest. During an emergency, epinephrine can be administered in 1
of 3 ways: intravenously, through an endotracheal tube, or through the
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
55
intraosseous method. The doses are slightly different, depending on the
route of administration. When given as a rapid push intravenously or into
the bone through the intraosseous method, the dose is administered as 0.1
mg of a 1:10,000 solution, given every 3 to 5 minutes, as needed.
Endotracheal administration is also given as a bolus dose; during ACLS,
epinephrine can be administered directly into the endotracheal tube when
ventilation is stopped momentarily to instill the medication directly. In this
method, the epinephrine is absorbed through the lungs. The dose to
administer when the drug is given through the endotracheal route is 2 to 2.5
mg epinephrine, diluted in 10 mL of normal saline.
Epinephrine is sometimes referred to as adrenaline, and it is associated with
the fight-or-flight mechanism. During times of acute stress, the sympathetic
nervous system is stimulated and body processes speed up, including heart
rate and muscle tone, as a result of the release of stress hormones,
including epinephrine. This natural occurrence increases the heart rate and
blood pressure normally in response to fear. Epinephrine then has a similar
effect when it is administered as a medication. At low doses, epinephrine
causes increased output; greater doses of epinephrine result in increased
MAP due to greater levels of vasoconstriction.
Of note, when a patient has suffered ischemia due to myocardial infarction,
epinephrine should be used with caution. The increase in blood flow and
cardiac contractility produced by the drug can raise blood pressure but also
increase demand for oxygenated blood for the heart. This may actually
cause the opposite of the intended effect by worsening ischemia.
Epinephrine can be used for the treatment of septic shock and is considered
the second choice of drug to administer, following norepinephrine.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
56
Additionally, epinephrine may be added to norepinephrine in some cases
that otherwise show poor response to initial treatment. Some studies have
shown that addition of epinephrine after initial norepinephrine dosing
resulted in improved hemodynamic parameters because the epinephrine is
thought to augment the effects of norepinephrine through is inotropic and
vasoconstrictive actions. The decision of whether to add epinephrine after
initial dosing with norepinephrine in cases of septic shock should be based
on the patient’s clinical response.
The patient’s clinical status will often be the first indicator of whether
epinephrine administration has been successful in improving cardiac output
and blood pressure. Typically, epinephrine is administered in situations
where the patient is already receiving continuous hemodynamic monitoring,
which will reflect sometimes even minor fluctuations in MAP and central
venous pressure. The patient’s response is a useful indicator to guide
administration of epinephrine, whether by hemodynamic changes following
continuous infusion or by rapid bolus to stimulate the heart after arrest.
Norepinephrine
Norepinephrine is a naturally-occurring neurotransmitter in the body that
affects the sympathetic adrenergic nerves. It is synthesized and released
from the nerves following a combination of steps involving the release of the
amino acid tyrosine, which is converted to DOPA and then to dopamine,
which acts as a precursor and facilitates release of norepinephrine.1,37-40,86
Following release, much of the norepinephrine is eventually taken back up
into the nervous system; however, some is also released into capillary
circulation. Larger amounts of sympathetic stimulation lead to an increase in
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
57
norepinephrine release into circulation, which causes vasoconstriction and
supports cardiac contractility.
When administered in the clinical care setting, norepinephrine may be called
by its brand name of Levophed™. It acts as an alpha-adrenergic receptor
agonist to cause vasoconstriction, thereby increasing blood pressure and
relieving some hypotension. Note that alpha-adrenergic receptors are not
located within the skeletal muscles, as the beta receptors are. This is
because when the alpha receptors are stimulated, they constrict, which is
good for central blood pressure, but vasoconstriction within the muscle
tissue is not necessarily helpful in the relief of hypotension and the skeletal
muscles need to keep these arteries dilated in order to receive as much
blood flow as possible. Norepinephrine also acts on the beta-adrenergic
receptors of the heart to dilate the coronary arteries, resulting in more blood
flow to the heart and improving its ability to contract.
Norepinephrine is primarily used for the management of significant
hypotension caused by certain disease states. It may also be administered in
cases of cardiac arrest that result in life-threatening hypotension.
Norepinephrine is always administered by intravenous injection, preferably
into a central line rather than a peripheral IV.
Due to its vasoconstrictive effects, norepinephrine has the potential to cause
side effects associated with hypoxia from a lack of blood flow to certain
tissues. While vasoconstriction can improve blood pressure, it can also
increase the risk of obstruction within circulation, possibly leading to tissue
ischemia. Other side effects that have been noted with norepinephrine
include bradycardia, cardiac arrhythmias, anxiety, headache, and respiratory
difficulties. When norepinephrine is administered as continuous infusion, the
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
58
patient should also receive concomitant fluid and electrolyte therapy to
support circulation and blood pressure maintenance. This recommendation
also prevents the significant drop in blood pressure that could occur when
norepinephrine is discontinued.
The typical rate of administration of norepinephrine for adult patients is
between 0.01 and 0.2 mcg/kg/minute. If possible, when first administering
norepinephrine for correction of hypotension, the infusion rate should start
out slowly and the patient should be monitored closely for the effects of the
drug. The blood pressure level, once increased to a low-minimum systolic
level (~90 to 100 mmHg) can then be maintained with the current rate of
norepinephrine to avoid organ and tissue ischemia.
When vasopressors are needed to sustain adequate blood pressure in the
critical care setting, early administration of norepinephrine is preferable to
delaying administration and has been shown to reduce overall mortality in
ICU patients. A study by Bai, et al., in the journal Critical Care showed that
timing of vasopressor administration matters more than the actual kind of
vasopressor given and that a greater delay in administration of
norepinephrine for treatment of hypotension associated with septic shock
was related to a significantly increased risk of death. The study showed that
in cases of septic shock that were under review, for every one-hour delay
that norepinephrine was initiated, there was an increase in mortality rate by
5.3 percent. Each case may vary slightly in which vasopressors are needed
and the actual time of the drug is given. As discussed, there are some cases
in which fluid resuscitation is needed to correct hypovolemia before pressors
such as norepinephrine can be given; alternatively, sometimes excess fluid
volume is unnecessary to correct hypotension and would actually be
detrimental to the patient’s condition. When this occurs, the delay of
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
59
administering norepinephrine has been shown to be harmful for some
patients.
In cases of septic shock, norepinephrine is considered the first choice of
vasopressor to use for correction of arterial blood pressure. Researchers
arrived at this conclusion after extensive testing and analyses of research
results. Although dopamine can also be used as a vasoconstrictor,
norepinephrine works more rapidly than dopamine; it also produces a
stronger response that is more consistent in its effects. Further studies are
needed to consider the success of norepinephrine in comparison to other
types of vasopressor medications.
Phenylephrine
The drug phenylephrine is given to counteract the effects of hypotension,
particularly among patients undergoing anesthesia or those with septic
shock. Phenylephrine is an alpha-1 agonist, so it binds to these receptors in
the vascular smooth muscles to cause vasoconstriction.1,58,84-86,89
Prior to administering phenylephrine, the clinician should ensure that the
patient’s blood volume levels have been corrected, as the drug may not be
effective when hypovolemia is present. Further, metabolic acidosis may also
impact the effectiveness of phenylephrine, so patient monitoring with arterial
blood gases and for symptoms of respiratory compromise should be
considered and corrected prior to administration.
Phenylephrine may be given as a bolus dose or continuous infusion,
depending on the conditions in which it is administered. It is more likely to
be given as a bolus in cases where a patient has hypotension due to surgical
anesthesia. When administering a bolus, a typical initial dose is 50 to 250
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
60
mcg, with the patient being constantly monitored for blood pressure effects.
Following an initial bolus, an ongoing infusion of phenylephrine may be
needed, depending on patient response.
Phenylephrine may be administered as part of treatment for septic shock,
however it is not considered a first choice when compared to norepinephrine.
The Surviving Sepsis Campaign states that in cases of septic shock,
phenylephrine should only be used when norepinephrine could cause cardiac
arrhythmias, where the patient has consistently low blood pressure but not
decreased cardiac output, or as another resort when the patient has not
responded to other treatments. When given for treatment of shock,
phenylephrine should only be administered as continuous infusion and not as
a bolus dose. A dose of 0.5 to 6 mcg/kg/min may be given on a continuous
basis and titrated according to blood pressure response. Note that doses
greater than 6 mcg/kg/min are not necessarily associated with higher levels
of blood pressure.
In a manner similar to some other types of vasopressors, phenylephrine can
cause some negative effects associated with the cardiovascular system. It
may worsen cases of angina, if present, because it can affect the
vasoconstriction of the coronary vessels. Additionally, patients who have
suffered spinal cord injuries or have neurogenic shock should not be given
phenylephrine because it could cause reflex bradycardia. Finally, the use of
phenylephrine, when combined with other pressor drugs that cause
vasoconstriction, can have serious adverse effects, including ischemia. Any
patient who experiences bradycardia or symptoms of ischemia when being
monitored after phenylephrine administration should have the drug
discontinued and may need treatment with an alpha-adrenergic agonist to
counteract the effects.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
61
Ephedrine
Ephedrine is a drug that is derived from plants of the Ephedra genus; it is
used as a treatment for hypotension and for bronchodilation. Ephedrine acts
as an alpha- and beta-adrenergic receptor to stimulate heart contractions
and promote smooth muscle cell relaxation to improve breathing rates when
an individual is suffering from wheezing or asthma-associated conditions.1,109
Some patients, when recovering from anesthesia, may experience
hypotension, particularly following spinal anesthesia. Ephedrine may be
administered in these cases to counteract the hypotension and to raise blood
pressure. It is thought that the increase in blood pressure comes primarily
from increased cardiac output of ephedrine and less from peripheral
vasoconstriction.
Ephedrine is known as an adrenergic activator in that it has the added effect
of releasing norepinephrine from storage, which can be beneficial in the
circulatory system. The release of norepinephrine in turn affects the
adrenergic receptors to exert further effects, which is an indirect activity of
ephedrine.
Ephedrine is less commonly used as an ongoing infusion in the ICU when
compared to its use during surgery for treatment of anesthesia-induced
hypotension. The drug may also be administered prophylactically during
surgery to reduce the risk of low blood pressure, but the exact dose still
needs clarification. A study in the Journal of Anaesthesiology Clinical
Pharmacology found that administration of high-dose ephedrine (0.15
mg/kg) during surgery with general anesthesia can have a significant effect
in preventing hypotension associated with anesthesia induction. The study
compared high-dose ephedrine with low dose preparations (0.07 mg/kg) and
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
62
placebo, and the participants with the least decline in mean arterial
pressures were those who received high-dose ephedrine. The induction
agents in the study were propofol and remifentanil, however, other drugs
given with anesthesia administration can also cause hypotension that may
need further treatment with ephedrine.
Intravenous ephedrine has a half-life of up to 6 hours and duration of action
of 3 hours. It can take effect within 2 minutes of administration. Intravenous
administration of ephedrine for acute hypotension may be given as a bolus
dose or as continuous infusion. A bolus dose of ephedrine can be given as
200 to 300 mcg IV over 1 minute, and repeated in 15 minutes for effect.
This bolus can also be followed by continuous infusion at a rate of 5 to 20
mcg/minute.
When given for treatment of bronchospasm associated with asthma,
ephedrine may be given as an inhaled preparation. A dose of inhaled
ephedrine is given as 100 to 200 mcg (1 to 2 puffs) through metered-dose
inhaler, every 4 hours, or 5 mg diluted in 10 mL of sodium chloride every 4
to 6 hours when given through a nebulizer. Note that ephedrine is not
necessarily a first choice of treatment for bronchospasm; while useful in
releasing constricted bronchioles, there are other agents that may be more
therapeutic in these cases.
Ephedrine has the potential to produce positive outcomes in patients with
unstable blood pressure, although it may not be used as commonly as some
other vasopressors. However, because it exerts both direct and indirect
adrenergic activity, ephedrine can be considered as a treatment used in the
same methods as some catecholamine drugs, including norepinephrine and
epinephrine.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
63
Vasopressin
Vasopressin is a hormone that can be added to some of the more powerful
vasopressors used to control blood pressure (epinephrine, norepinephrine).
The addition of vasopressin may further support vasoconstriction to resolve
hypotension.1,85-87,106,109
As noted, vasopressin acts on V receptors, found throughout the blood
vessels, kidneys, liver, and the brain, to regulate vasoconstriction, body
temperature, and urine output. Vasopressin can control some intravascular
volume by exerting antidiuretic effects to maintain fluid in the body instead
of allowing it to be excreted as urine. Vasopressin does not necessarily
increase blood pressure levels when administered to healthy adults, but
when given to those who are already suffering from hypotension as a result
of disease states, it can produce significant changes in blood pressure. It is
indicated for the treatment of hemorrhage, such as in cases of bleeding
esophageal varices, to reduce the overall rate of blood loss.
During cases of septic shock, vasopressin may be added along with
norepinephrine to assist with raising blood pressure levels if the patient is
otherwise unresponsive to other pressor therapy. Historically, vasopressin
was administered as part of ACLS protocol for treatment of cardiac arrest,
but it was removed from the algorithm in 2015.
Vasopressin has a half-life of up to 20 minutes, so it is often given as
continuous IV infusion to exert its effects. For cases of septic shock,
vasopressin is administered at a rate of 0.01 to 0.04 units/hour.108 This
infusion rate increases SVR while maintaining normal blood flow in other
vital areas, including the brain, lungs, and kidneys. Vasopressin may cause
some adverse effects related to blood flow due to vasoconstriction; however,
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
64
side effects are not as common when the drug is given in smaller doses. One
of the more common effects is myocardial ischemia, which can occur if
vasopressin causes significant constriction of the coronary blood vessels,
thereby reducing blood flow to the heart.
Vasopressin analogs are drugs that are similar to antidiuretic hormone in
that they exert many of the same effects, but they do not have the same
chemical structures. One of the more commonly administered vasopressin
analogs is terlipressin, which may have some advantages over vasopressin
itself.
Terlipressin is a type of synthetic vasopressin analog that can be used for
management of low blood pressure in cases where there is acute blood loss,
such as with treatment of bleeding esophageal varices. In situations such as
septic shock when the first drug of choice, norepinephrine is unsuccessful,
terlipressin may be administered instead. In studies among animal models
studying treatment of hemorrhagic shock, administration of terlipressin has
been shown to be beneficial when given during the early stages. A review in
the journal BioMed Research International showed that in some cases of
hemorrhagic shock, vasopressin was more effective than other types of
vasopressors. Note that vasopressin or terlipressin are not indicated for use
as the sole pressor for support in cases of shock, including septic shock.
A patient who experiences hypotension as a result of shock or bleeding can
benefit from administration of vasopressin. While the drug is often not a
strong enough vasopressor to be used entirely alone in very critical
situations, it is a useful adjunctive medication that can support other
pressors in targeting low blood pressure.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
65
Nitroglycerin
Nitroglycerin (Nitrostat®, NitroMist®) is a nitrate medication primarily used
for the treatment of chest pain associated with angina, as well as for some
patients experiencing myocardial infarction, to some people with heart
failure or those suffering severe hypertension, and for patients following
certain types of cardiac surgery.1,53,55,56,98
Nitroglycerin was discovered for its use as a medication over 150 years ago
and is commonly employed as a first-line treatment for patients experiencing
cardiac ischemia. The drug is a nitrate that releases the chemical compound
nitric oxide. In turn, the nitric oxide activates guanylate cyclase, a type of
enzyme that promotes formation of guanosine 3'5' monophosphate in the
smooth muscles. The smooth muscles of the blood vessels are regulated by
myosin light chains; these chains play a significant role in the contraction of
the blood vessels to control vasodilation and vasoconstriction. As a result of
the creation of guanosine 3’5’ monophosphate, the myosin light chains are
altered through dephosphorylation, leading to relaxation of the muscle cells
and consequent vasodilation.
Angina develops when the coronary blood vessels that supply blood to the
heart become blocked and blood flow is reduced. Most often, this obstruction
occurs as a result of coronary artery disease. This feeling is often temporary
and can be alleviated by taking a drug such as nitroglycerin to increase the
size of the coronary blood vessels and to improve blood flow. An individual
who experiences angina may have one of two forms: stable or unstable
angina. Stable angina describes the feelings of discomfort that occur after
activity or exercise. Increased activity results in increased oxygen demands
and blood supply to the heart, but if the coronary blood vessels are
occluded, angina can develop. Unstable angina occurs when the individual
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
66
experiences chest pain in the absence of increased activity or movement;
the discomfort occurs even when there is not a particular increased demand
for oxygenated blood to the heart.
Nitroglycerin has been shown to improve discomfort associated with both
stable and unstable angina. For many people who have been diagnosed with
coronary artery disease and who experience angina, a typical dose as
prescribed may be taken at the onset of chest pain. For example, someone
who has stable angina and has developed chest pain may administer 1 or 2
sublingual sprays of nitroglycerin to alleviate the pain. If the chest pain
remains unresolved after self-administration of nitroglycerin, the person may
go to the emergency department for further help.
Nitroglycerin is available in a variety of forms and routes for administration.
The most appropriate route to use depends on the patient’s current condition
and his ability to take the medication. Nitroglycerin can be administered
sublingually to be dissolved, as a sublingual spray into the mouth, as an oral
tablet or capsule (available as regular and extended-release formulations);
as a transdermal patch, typically applied to the chest or back; in ointment
form, in which the medication is smoothed onto the skin, and as an
intravenous dose.
Sublingual tablets of nitroglycerin are available as compressed tablets that
can dissolve under the tongue. The sublingual route of administration is
most commonly used for management of angina, whether in the emergency
department or when the patient is at home and prior to arrival for care. The
sublingual form is available in three different strengths: 0.3 mg, 0.4 mg, and
0.6 mg. For the patient who is complaining of angina, one sublingual tablet
may be given every five minutes until angina is controlled, however,
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
67
administration of more than three tablets in 15 minutes requires further
medical care. Sublingual nitroglycerin is primarily metabolized by the liver,
and metabolism is the primary route of drug elimination. It has a half-life of
approximately 2 to 3 minutes, and the effects remain for up to 25 minutes
after administration.
A myocardial infarction is a clinically serious situation, even if it may present
with similar symptoms as angina. Unstable angina itself may progress to
myocardial infarction; the two conditions are sometimes confused upon the
patient’s initial presentation for care. Myocardial infarction also often
develops as a result of coronary artery disease, but rather than causing a
temporary blockage in the coronary arteries, portions of the heart tissue die
from lack of oxygen. The cell injury causes a rise in cardiac enzymes that
can be identified upon laboratory testing. The heart’s function, particularly
the left ventricle, eventually becomes strained. Ejection fraction decreases,
leading to electrical conduction abnormalities that are noted on ECG,
particularly as ST-T segment changes. Eventually, the patient experiences
heart failure and a shock state that includes inadequate perfusion to vital
organs.
In the inpatient setting, nitroglycerin is also administered to patients who
are experiencing myocardial ischemia. It may also be implemented following
open-heart surgery, including during the post-op period after coronary
artery bypass grafting (CABG) to maintain blood flow and vasodilation, and
because the risk of coronary artery spasm during this period is elevated.
Because of its effects on the blood vessels, nitroglycerin reduces the strain
on the heart by decreasing preload to decrease overall oxygen demand.
When the veins dilate from the action of the drug, there is a slight increase
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
68
in blood pooling in the peripheral tissues and consequent decrease in venous
blood return to the heart, which causes the decreased preload.
In addition to a decrease in preload, nitroglycerin reduces afterload through
a decrease in arterial venous pressure with dilation of the arteries.
Additionally, dilation of the coronary vessels improves oxygen supply to the
heart, so the effects of nitroglycerin are actually two-fold: it has the ability
to balance the supply-demand relationship between oxygen and nutrients in
the heart when ischemia occurs.
Nitroglycerin is also used for the treatment of severe hypertension, as its
vasodilatory effects increase the size of blood vessels and cause a reduction
in blood pressure levels. The effects on the venous circulation lead to a
reduction in central venous pressure when levels are high and left
ventricular cardiac output is improved because of decreased systemic
vascular resistance. Because of its effects, nitroglycerin should not be
administered with some other drugs that can cause synergistic outcomes.
For example, use of nitroglycerin with a patient who has a prescription for
sildenafil for pulmonary hypertension can cause a rapid drop in blood
pressure and should be avoided. Although nitroglycerin is used for severe
hypertension, it should also not be given to any patient who is experiencing
hypertensive encephalopathy because it can cause an increase in intracranial
pressure.
Long-term use of nitroglycerin may cause deleterious effects for the patient,
particularly in response to some vasoconstricting drugs. Ferreira, et al., in
the Circulation Journal state that prolonged use of nitroglycerin can lead to
changes in the heart muscle cells that may lead to an increase in infarct size
when myocardial infarction is present. Additionally, repeated and ongoing
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
69
doses of nitroglycerin may result in pharmacological resistance and a
decreased effect. This nitrate tolerance that develops with consistent use of
nitroglycerin causes a loss of the therapeutic effects on the cardiovascular
system, requiring higher doses each time to achieve the same outcomes. To
avoid nitrate tolerance that may develop with this drug, the patient may
need to have breaks from the drug, known as nitrate-free intervals for
several hours per day.
When administering nitroglycerin as an intravenous infusion, the dose must
be diluted first within a dextrose solution or in normal saline. An initial adult
starting dose of IV nitroglycerin is approximately 5 mcg/minute as an
infusion, increasing the dose as needed every 3 to 5 minutes by 5
mcg/minute each time, until a maximum dose of 20 mcg/minute. The
provider may continue to increase the dose incrementally to achieve desired
effects, but this process should be considered on a case-by-case basis. The
patient should be continuously monitored through drug administration for
the presence of adverse effects as well as signs of drug effectiveness and
hemodynamic stability.
Nitroglycerin should always be administered with caution, with the patient
carefully monitored throughout the time of dosing to determine if any ill
effects have developed. Additionally, nitroglycerin may cause headache, and
symptoms of low blood pressure, including dizziness, weakness, palpitations,
pallor, and diaphoresis. The dose of nitroglycerin can cause very rapid and
powerful effects in the patient, leading to relief of angina and improved
circulation, but also a risk of hypotension and further ischemia.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
70
Nitroprusside
Sodium nitroprusside (Nitropress®) is a potent vasodilator that increases
the size of the arteries and veins after administration. It is most commonly
administered for patients in hypertensive crisis.1,57,58,
Nitroprusside induces a drop in blood pressure by its effects on
oxyhemoglobin; when combined, nitroprusside splits to form methemoglobin
while simultaneously releasing nitric oxide. This reduces intracellular calcium
in the smooth muscle cells and contributes to vasodilation. Although sodium
nitroprusside can have significant effects on circulation, its impact on cardiac
output is less consistent when compared to nitroglycerin. As with
nitroglycerin, a small amount of pooling of blood in the peripheral tissues
can decrease pressure on the heart and may lead to a decrease in venous
return to the heart as well as decreased blood pressure.
Nitroprusside is given by continuous IV infusion and not as a bolus injection.
The usual rate of infusion for adults is approximately 0.5 – 4
mcg/kg/minute. The dose should start at a slower rate, increasing as the
patient tolerates and depending on clinical response. Nitroprusside takes
effect within a few seconds after administration. It has an approximate halflife of 2 to 3 minutes, which requires continuous infusion for ongoing effects.
All patients who receive sodium nitroprusside should be monitored
continuously for side effects, effects of the drug, and to maintain
hemodynamic stability, particularly for blood pressure.
Because of its effects on blood pressure, nitroprusside can cause significant
hypotension, which can be corrected by stopping the infusion. The patient
may suffer such severely low blood pressure that vital organs suffer from a
lack of perfusion. Prolonged infusion of the drug can also exacerbate
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
71
myocardial ischemia when the vasodilatory effects increase the oxygen
requirements of the heart. The coronary vessels benefit from the effects of
nitroprusside, however, other areas may divert blood to support the cardiac
cells but can then become depleted and develop ischemia.
Prolonged administration of nitroprusside is also associated with cyanide
toxicity and elevated methemoglobin levels. When nitroprusside combines
with oxyhemoglobin and releases nitric oxide, it also releases free cyanide.
In small amounts, this may have negligible effects, however, there is
potential for toxicity when the infusion rate of the nitroprusside is faster than
the rate of cyanide excretion. A patient who has developed cyanide toxicity
may exhibit confusion and tachypnea; laboratory evaluations typically
manifest as metabolic acidosis and the venous blood sample may appear
bright red. If symptoms of cyanide toxicity develop, the nitroprusside
solution should be discontinued and the patient should be given sodium
thiosulfate, as well as 100 percent oxygen. An alternative drug with similar
effects may need to be employed; other drugs such as labetalol, nicardipine
(Cardene®), and fenoldopam (Corlopam®) all have similar antihypertensive
effects as sodium nitroprusside but without the risk of cyanide toxicity.
Additionally, nitroprusside administration may increase the risk of
methemoglobinemia, although this effect is often only associated with high
levels of drug administration. Nitroprusside forms methemoglobin when it
combines with carboxyhemoglobin after administration. Elevated levels of
methemoglobin can then lead to methemoglobinemia, in which the patient
experiences cyanosis and shortness of breath because the hemoglobin is
unable to bind to oxygen in the bloodstream.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
72
Nitroprusside affects all areas of the circulatory system to promote healthy
blood pressure levels because it is non-selective. It contributes to increased
circulation in the brain by dilating the cerebral blood vessels. It should
therefore be used with extreme caution among patients at risk of increased
intracranial pressure, as the effects of nitroprusside can contribute to such
an increase in cerebral blood flow as to worsen elevated intracranial
pressure. Most people who receive nitroprusside in the hospital are already
on continuous hemodynamic monitoring and may have continuous arterial
pressure monitoring, which is beneficial for ongoing evaluation of blood
pressure and patient response to the drug. Overall, the use of nitroprusside
requires a distinct balance of administering enough of the drug to counteract
hypertension and avoid severe consequences of hypertensive crisis, while
eluding such a drop in blood pressure as to cause other adverse effects.
Labetalol
Labetalol is a beta-blocker medication that is primarily used for the
treatment of severe hypertension. It is an adrenergic receptor antagonist
that blocks the actions of alpha-1 as well as beta-adrenergic receptors. The
drug is selective for alpha-1 receptors but is non-selective for beta
receptors. Its effects on these receptors lead to a decrease in
atrioventricular condition and sinoatrial discharge, a decrease in the force of
heart muscle contractions, decreased systemic vascular resistance, and
vasodilation.1,59,110
Labetalol’s effects on peripheral vascular resistance, as well as an increase in
cardiac output occur with mixed effects and are not always consistent in all
patients. Labetalol may be administered as an oral tablet; a prescription for
the drug is sometimes given to patients with hypertension to control blood
pressure and to maintain normal levels when it is taken at home. When
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
73
given orally, labetalol has the same effect on the cardiovascular system as
when it is given intravenously, but the effects of oral dosing take longer
because of the added step of drug absorption after administration. Oral
labetalol may be started for hospitalized patients after adequate blood
pressure levels have been achieved with IV infusion. Once ready to start oral
labetalol, the initial dose is 200 mg, which can be repeated in 6 to 12 hours,
depending on patient response.
Labetalol is typically administered as an IV infusion for hospitalized patients;
it may be given as an IV injection or as continuous dose. Individual
injections are given slowly over the course of 2 minutes, with repeat doses
given after 10 minutes, depending on the patient’s blood pressure response.
Continuous infusion must be given with the dose diluted in solution and the
dose and rate titrated according to the patient’s blood pressure response.
The patient who receives labetalol should be on continuous hemodynamic
monitoring to assess blood pressure levels.
The most common side effect associated with labetalol is orthostatic
hypotension. As the side effects are worsened when the patient is not lying
down, anyone who receives labetalol and who develops hypotension should
be kept supine or assisted to lie in the supine position. When starting an
infusion of labetalol, the patient should be lying down to prevent the risk of
orthostatic hypotension and to decrease the effects of low blood pressure if
it should develop. Additionally, labetalol should not be given to patients who
already have a history of hypotension or cardiogenic shock, those with
bradycardia, heart failure, or greater than first-degree heart block. Other
side effects of labetalol include dizziness, lightheadedness, fatigue, and
headache.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
74
Labetalol may also be used in patients who have increased intracranial
pressure associated with a brain injury. Acute intracranial hypertension
describes a state in which intracranial pressure (ICP) is sustained above 20
mmHg. The condition may develop as a result of massive stroke,
intracerebral hemorrhage, or traumatic brain injury, and it typically requires
intensive and critical patient care. One element of managing intracranial
hypertension is to optimize cerebral perfusion pressures. Administration of
labetalol is one method of lowering ICP. A review by Ragland, et al., in the
Journal of Neurocritical Care recommended that administration of a shortacting blood pressure lowering agent such as labetalol could decrease the
patient’s MAP, which may then cause a reduction in the ICP.
Despite the negative effects associated with high blood pressure, too rapid of
vasodilation could occur with drug administration, causing hypotension. As
result, blood pressure levels must be continuously monitored with labetalol
use, not only during the infusion, but also for time afterward until the drug
has cleared the body to ensure that the patient remains in a stable clinical
state.
Summary
The safe administration of medications to critically ill patients is part of the
overall goals of care for this population. Effective drug administration
involves using critical thinking skills to determine the most appropriate drug
for the situation based on knowledge of its therapeutic effects, and being
able to respond to changes in the patient’s clinical status after the drug has
been given. This specific population of patients is particularly vulnerable to
changes in medication dosages and to mistakes that could happen with
improper medication administration. Identifying the most appropriate
methods of administration, as well as possible complications of medications
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
75
in the critical care and emergency settings is essential for providing effective
care.
Because the patients being cared for in the ICU and ED often have unstable
conditions, administration of medications can lead to rapid changes. When
drugs are administered inappropriately, there is a greater chance of harm to
the patient, even if the incorrect action would be considered a minor error if
it were made outside the ICU and ED setting. Most patients in critical care
are sicker overall when compared to their counterparts in other areas of the
healthcare facility; they often have higher numbers of comorbidities present
and they receive more medications. Critical care patients also undergo more
treatments and procedures that can induce pain or anxiety and so they may
have more medications given as needed for comfort as well.
Ideally, the clinician should be familiar with the common drugs used to treat
critical care patients, including common drug interactions. Being familiar
with a drug’s time of onset, duration, and half-life will help to support clinical
decision-making during a patient’s course of care. By utilizing reference
guides, checking with other personnel, and using medical equipment
appropriately, the clinician can safely administer medications and achieve
benefit the patient.
Please take time to help NurseCe4Less.com course planners evaluate
the nursing knowledge needs met by completing the self-assessment
of Knowledge Questions after reading the article, and providing
feedback in the online course evaluation.
Completing the study questions is optional and is NOT a course
requirement.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
76
1. Within the ICU and critical care environment, metered-dose
inhalers (MDIs) typically include medication formulations that
have been created for MDIs, such as
a.
b.
c.
d.
inhalable powder medications.
any drug available in nebulized form.
powder, liquid and water-soluble gel forms.
bronchodilator medications and corticosteroids.
2. True or False: Pharmacokinetics in critical care patients are the
only constant factors because drugs are absorbed, metabolized,
and excreted based on the drug’s composition, not the current
health status of the patient.
a. True
b. False
3. The following statement(s) is/are correct with respect to the use
of inhaled medications in the critical care environment, such as
ICU?
a. Inhaled medications are rarely used in ICU.
b. Inhaled medications are used except in patients who require
mechanical ventilation.
c. The method of administering inhaled drugs depends largely on the
patient’s ability and health status.
d. All of the above
4. _______________ is a muscarinic agonist that is used in an
inhaled preparation form to test and diagnose asthma.
a.
b.
c.
d.
Methacholine
Budesonide
Ipratropium bromide
Albuterol
5. Which of the following inhaled medications specifically act on the
beta-2 adrenergic receptors of the lungs to cause vasodilation of
the bronchioles and to improve breathing?
a.
b.
c.
d.
Ipratropium
Heparin
Methacholine
Albuterol
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
77
6. True or False: Intubated patients may also receive inhaled
medications when the drug is administered through the ventilator
tubing.
a. True
b. False
7. Muscarinic receptors are a type of acetylcholine receptor that can
be found in the
a.
b.
c.
d.
lung tissue.
neuromuscular junction.
skeletal muscles.
liver.
8. When stimulated, muscarinic receptors cause
a.
b.
c.
d.
an increase in heart rate.
vasodilation.
constriction of the bronchioles.
All of the above
9. ______________ is given as an inhaled medication to block the
muscarinic receptors and to cause bronchodilation, which
increases airflow in the lungs and makes it easier for the patient
to breathe.
a.
b.
c.
d.
Methacholine
Albuterol
Ipratropium
Isoproterenol
10. Clinical trials have shown that ____________, a beta-2
receptors stimulator, has a greater effect on smooth muscle
relaxation in the bronchial tissue than isoproterenol with fewer
cardiovascular effects than isoproterenol.
a.
b.
c.
d.
azithromycin
tobramycin
methacholine
albuterol
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
78
11. The most common side effects of ipratropium include
a.
b.
c.
d.
vasodilation.
bronchodilation.
an increase in heart rate.
exacerbation of COPD symptoms.
12. The American College of Chest Physicians’ and the American
College of Asthma, Allergy, and Immunology’s guidelines for
delivery of short-acting beta-2 agonist through an MDI or
nebulizer in cases of acute asthma and bronchospasm include:
a. use of an MDI is not recommended.
b. delivery through an MDI or nebulizer is appropriate, based on the
patient’s ability to accurately use these devices.
c. use of dry powder inhalers is recommended over MDI or nebulizer.
d. the use of dry powder inhalers is recommended based on the
patient’s ability to use this device.
13. Nebulizers known as ________________ work by breaking
down the liquid into particles using compressed oxygen or air
and a reservoir.
a.
b.
c.
d.
Jet nebulizers
Bronchodilators
Mesh nebulizers
Ultrasonic nebulizers
14. True or False: According to the American College of Chest
Physicians and the American College of Asthma, Allergy, and
Immunology, patients who are not using mechanical ventilation
but who are severely dyspneic, should not use intermittent or
continuous nebulizers to administer medications.
a. True
b. False
15. Which type of nebulizer is not used as often within the ICU
because of its size and cost to use?
a.
b.
c.
d.
Jet nebulizers
Dilator nebulizers
Mesh nebulizers
Ultrasonic nebulizers
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
79
16. There is also less risk of contamination associated with the use
of ______________ nebulizers because the reservoir is
separate from the ventilator circuit.
a.
b.
c.
d.
jet
dilator
mesh
ultrasonic
17. True or False: Bronchodilators are some of the more common
drugs administered by inhalation; however, antibiotics,
including tobramycin and azithromycin, can be administered in
this method as well.
a. True
b. False
18. Intravenous administration of medications act very quickly and
produce rapid responses because they are administered directly
into systemic circulation while
a.
b.
c.
d.
eliminating the risk of infection from administering drugs.
bypassing the distribution stage.
bypassing the absorption stage.
bypassing the blood-brain barrier system.
19. Part of the calculation for the IV flow rate includes the
______________________, which is the amount of the drug
that is available within the given solution.
a.
b.
c.
d.
drug concentration
medication dose
calculate drops (gtts) per minute
time-spacing of drug administration
20. When a continuous infusion is in place for more than 24 hours,
the IV tubing and the medication container often must be
changed
a.
b.
c.
d.
to
to
to
to
adjust the rate of administration.
decrease the drug concentration.
catch any errors of drug concentration.
decrease the risk of infection.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
80
21. True or False: The nurse should be familiar with the basic units
of common drugs that are given to be able to catch any errors of
concentration if they occur.
a. True
b. False
22. A nurse receives an order for 1000 mL D5 ½ NS to be given over
8 hours. To calculate the infusion rate when a pump will be
used, the nurse would ______________________ to obtain the
mL/hour.
a.
b.
c.
d.
divide 8 hours by 1000 mL D5 ½ NS
need to know drops (gtts) per minute
multiply 60 minutes times 8
divide 1000 mL D5 ½ NS by 8 hours
23. The size of the drip set may range from a mini-drip set to a
regular drip set. A mini-drip set has a gtt factor (drops per
minute) of
a.
b.
c.
d.
10-20 gtts/mL.
15 gtts/mL.
60 gtts/mL.
25 gtts/mL.
24. A nurse receives an order for Ancef, with the dose in a 50 mL
solution, which must be given over 30 minutes. The gtt factor is
20 gtts/mL. The nurse uses the following calculation:
a.
b.
c.
d.
(20 gtt ÷ 50 mL) x 30 minutes = 12 gtts/minute.
(50 mL ÷ 20 gtt) x 30 minutes = 75 gtts/minute.
20 gtt x 30 minutes ÷ 50 mL = 12 gtts/minute.
50 mL x 20 gtt ÷ 30 minutes = 33.3 gtts/minute.
25. True or False: Before administration of certain intravenous
medications, the clinician should be familiar with all possible
effects of all drugs.
a. True
b. False
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
81
26. Oral medications are not as commonly administered in critical
care environments when compared to intravenous drugs
because
a. oral medications are never the easiest way to administer drugs.
b. many critically ill patients do not have the ability to swallow oral
tablets.
c. oral administration is not effective in ICU settings.
d. oral administration requires drug distribution, whereas IV does not.
27. _________________ typically act as sedative-hypnotics in the
central nervous system in response to GABA receptors.
a.
b.
c.
d.
Butyrophenones
Haloperidol
Benzodiazepines
Droperidol
28. Benzodiazepines are often administered to patients in critical
care to control
a.
b.
c.
d.
confusion.
hallucinations.
pain and distress.
symptoms from glaucoma.
29. Lorazepam is a benzodiazepine that has been shown
a.
b.
c.
d.
to be beneficial in controlling seizure activity.
to impact the cardiovascular system regularly.
to be beneficial with a reduced risk of delirium.
All of the above
30. True or False: Splitting tablets to administer one-half of a dose
is a relatively common practice but it also increases the risk of
errors.
a. True
b. False
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
82
31. Which of the following benzodiazepines, used in critical care,
has a half-life of up to 120 hours?
a.
b.
c.
d.
Lorazepam
Propofol
Midazolam
Diazepam
32. ____________ is a sedative-hypnotic medication that is most
commonly used to induce anesthesia during surgery.
a.
b.
c.
d.
Diazepam
Propofol
Midazolam
Lorazepam
33. ____________________ are a type of antipsychotic medication
that may be administered for the management of various
conditions, including acute psychosis or confusion.
a.
b.
c.
d.
Benzodiazepines
Neuroleptic medications
Opioid analgesics
Butyrophenones
34. When propofol is administered intravenously
a.
b.
c.
d.
its effects begin within approximately 40 seconds.
it has a half-life of 4 hours.
it cannot be used for long procedures.
it is best used together with analgesic drugs.
35. True or False: Historically, haloperidol has been a first choice of
treatment of ICU delirium, however, it does carry an increased
risk of adverse effects, some of which could be life-threatening.
a. True
b. False
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
83
36. _________________ are the first-line drug of choice to treat
non-neuropathic pain in critically ill adult patients.
a.
b.
c.
d.
Neuroleptic medications
Butyrophenones
Opioid analgesics
Benzodiazepines
37. Which of the following opioid analgesics is not recommended in
critically ill patients because of its risks of causing
neurotoxicity?
a.
b.
c.
d.
Methadone
Meperidine
Hydromorphone
Remifentanil hydrochloride
38. ______________________ is a vasopressor medication most
commonly administered for the control of blood pressure and
prevention of hypotension.
a.
b.
c.
d.
Meperidine
Ibuprofen
Ketorolac
Dopamine hydrochloride
39. Another element that must be considered with ____________
administration is its lipophilic tendencies, in that it has the
potential to accumulate in the adipose tissue of the patient.
a.
b.
c.
d.
meperidine
ibuprofen
propofol
ketorolac
40. ________________is a beta-blocker medication that is
primarily used for the treatment of severe hypertension.
a.
b.
c.
d.
Dobutamine
Labetalol
Ketorolac
Isoproterenol
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
84
CORRECT ANSWERS:
1. Within the ICU and critical care environment, metered-dose
inhalers (MDIs) typically include medication formulations that
have been created for MDIs, such as
d. bronchodilator medications and corticosteroids.
“Within the ICU and critical care environment, metered-dose inhalers
(MDIs) may also be used; their use is restricted to those medication
formulations that have been created for this specific mechanism of
administration, and typically include bronchodilator medications and
corticosteroids…. Metered-dose inhalers are very easy to use with
the ventilator, however, not all drugs that are given as inhaled
products are available through this device and must be given in
nebulized form instead.”
2. True or False: Pharmacokinetics in critical care patients are the
only constant factors because drugs are absorbed, metabolized,
and excreted based on the drug’s composition, not the current
health status of the patient.
b. False
“Pharmacokinetics in a critical care patient may be altered because
of the patient’s current health status; in other words, because critical
illness can affect how drugs are absorbed, metabolized, and
excreted, patients in the critical care environment are at higher risk
of complications associated with drug administration when their
bodies cannot process the drugs properly.”
3. The following statement(s) is/are correct with respect to the use
of inhaled medications in the critical care environment, such as
ICU?
c. The method of administering inhaled drugs depends largely on the
patient’s ability and health status.
“Inhaled medications are those drugs that are delivered to the lungs
and that are taken into the body while breathing in. They may be
commonly administered in the critical care environment, particularly
in situations where patients have breathing difficulties due to chronic
lung disease or bronchospasm, as well as among some patients who
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
85
require mechanical ventilation. The method of administering inhaled
drugs depends on the patient’s ability to take the medication, often
as a result of the patient’s health status.”
4. _______________ is a muscarinic agonist that is used in an
inhaled preparation form to test and diagnose asthma.
a. Methacholine
“… methacholine is an inhaled preparation that is a muscarinic
agonist that is used to test and diagnose asthma because it can
cause shortness of breath and wheezing.”
5. Which of the following inhaled medications specifically act on the
beta-2 adrenergic receptors of the lungs to cause vasodilation of
the bronchioles and to improve breathing?
d. Albuterol
“Certain inhaled medications specifically act on the beta-2 adrenergic
receptors of the lungs to cause vasodilation of the bronchioles and to
improve breathing. Albuterol (Proventil®, Ventolin®) is an example
of this type of medicine.”
6. True or False: Intubated patients may also receive inhaled
medications when the drug is administered through the ventilator
tubing.
a. True
“Intubated patients may also receive inhaled medications when the
drug is administered through the ventilator tubing.”
7. Muscarinic receptors are a type of acetylcholine receptor that can
be found in the
a. lung tissue.
“Muscarinic receptors are a type of acetylcholine receptor that can be
found in the lung tissue. They are responsible for controlling and
modifying smooth muscle tone, regulating mucus production, and
managing lung inflammation.”
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
86
8. When stimulated, muscarinic receptors cause
c. constriction of the bronchioles.
“When stimulated, muscarinic receptors cause a decrease in heart
rate, a decrease in cardiac contractility, and constriction of the
bronchioles.”
9. ______________ is given as an inhaled medication to block the
muscarinic receptors and to cause bronchodilation, which
increases airflow in the lungs and makes it easier for the patient
to breathe.
c. Ipratropium
“Ipratropium is given as an inhaled medication to block the
muscarinic receptors and to cause bronchodilation, which increases
airflow in the lungs and makes it easier for the patient to breathe.
Ipratropium can also decrease the amount of mucus secretions in the
patient’s lungs, which also promotes a clear airway and easier
breathing.”
10. Clinical trials have shown that ____________, a beta-2
receptors stimulator, has a greater effect on smooth muscle
relaxation in the bronchial tissue than isoproterenol with fewer
cardiovascular effects than isoproterenol.
d. albuterol
“Albuterol is often used as a rescue medication and it is the first
choice of treatment of bronchospasm and has been shown through
clinical trials to have a greater effect on smooth muscle relaxation in
the bronchial tissue than isoproterenol, a sympathomimetic drug that
also stimulates beta-2 receptors in the lungs, as well as having
longer-lasting effects and fewer cardiovascular effects than
isoproterenol.”
11. The most common side effects of ipratropium include
d. exacerbation of COPD symptoms.
“Ipratropium can also decrease the amount of mucus secretions in
the patient’s lungs, which also promotes a clear airway and easier
breathing. It may cause some negative side effects associated with
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
87
the respiratory system. The most common side effects of ipratropium
include respiratory tract infection, bronchitis, cough, sinusitis, and
exacerbation of COPD symptoms. Other side effects may also include
urinary tract infection, dyspepsia, and flu-like symptoms.”
12. The American College of Chest Physicians’ and the American
College of Asthma, Allergy, and Immunology’s guidelines for
delivery of short-acting beta-2 agonist through an MDI or
nebulizer in cases of acute asthma and bronchospasm include:
b. delivery through an MDI or nebulizer is appropriate, based on the
patient’s ability to accurately use these devices.
“The American College of Chest Physicians and the American College
of Asthma, Allergy, and Immunology have given guidelines about
selection of the most appropriate device and drug in different
situations within the emergency department or the ICU. In short, the
executive summary that was released determined that within the
emergency department, including among cases of acute asthma and
bronchospasm, the delivery of short-acting beta-2 agonist through
an MDI or nebulizer is appropriate, based on the patient’s ability to
accurately use these devices. The use of dry powder inhalers for
these same conditions is not recommended at this point due to a
lack of evidence regarding effectiveness.”
13. Nebulizers known as ________________ work by breaking
down the liquid into particles using compressed oxygen or air
and a reservoir.
a. Jet nebulizers
“Jet nebulizers are relatively easy to use and are one of the more
inexpensive methods of inhaled medication administration in the
ventilator-dependent population. Jet nebulizers work by breaking
down the liquid into particles using compressed oxygen or air and a
reservoir…. Ultrasonic nebulizers work by creating ultrasonic
vibrations that convert the medication solution into a mist that can
be inhaled…. The mesh nebulizer converts liquid to particles for
inhalation by moving the liquid through a fine mesh barrier.”
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
88
14. True or False: According to the American College of Chest
Physicians and the American College of Asthma, Allergy, and
Immunology, patients who are not using mechanical ventilation
but who are severely dyspneic, should not use intermittent or
continuous nebulizers to administer medications.
b. False
“Additionally, the two medical associations have issued guidelines for
the use of short-acting beta-2 agonists administered in the inpatient
hospital setting, which state that the use of metered-dose inhalers
and nebulizers, used with spacers when needed, are both
appropriate for administration of these drugs. Among patients who
are not using mechanical ventilation but who are severely dyspneic,
the use of either intermittent or continuous nebulizers to administer
medications is appropriate.”
15. Which type of nebulizer is not used as often within the ICU
because of its size and cost to use?
d. Ultrasonic nebulizers
“… ultrasonic nebulizers may leave some residual medication that the
patient does not receive. This type of nebulizer is not used as often
within the ICU because of its size and cost to use.”
16. There is also less risk of contamination associated with the use
of ______________ nebulizers because the reservoir is
separate from the ventilator circuit.
c. mesh
“Mesh nebulizers have been shown to have a reduced drug residual
with use, which means a greater amount of the inhaled drug reaches
the patient. There is also less risk of contamination associated with
their use because the reservoir is separate from the ventilator
circuit.”
17. True or False: Bronchodilators are some of the more common
drugs administered by inhalation; however, antibiotics,
including tobramycin and azithromycin, can be administered in
this method as well.
a. True
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
89
“Clearly, bronchodilators are some of the more common drugs
administered by inhalation; however, antibiotics, including
tobramycin and azithromycin, can be administered in this method as
well.”
18. Intravenous administration of medications act very quickly and
produce rapid responses because they are administered directly
into systemic circulation while
c. bypassing the absorption stage.
“Intravenous administration of medications is one of the most
common routes utilized in critical care. Many of these drugs act very
quickly and produce rapid responses because they are administered
directly into systemic circulation while bypassing the absorption
stage.”
19. Part of the calculation for the IV flow rate includes the
______________________, which is the amount of the drug
that is available within the given solution.
a. drug concentration
20. When a continuous infusion is in place for more than 24 hours,
the IV tubing and the medication container often must be
changed
d. to decrease the risk of infection.
“When a continuous infusion is in place for more than 24 hours, the
IV tubing and the medication container often must be changed to
decrease the risk of infection.”
21. True or False: The nurse should be familiar with the basic units
of common drugs that are given to be able to catch any errors of
concentration if they occur.
a. True
“The nurse should be familiar with the basic units of common drugs
that are given to be able to catch any errors of concentration if they
occur. The dose of the drug should be available through the
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
90
provider’s prescription and it should specify whether the drug should
be given over a period of minutes or hours.”
22. A nurse receives an order for 1000 mL D5 ½ NS to be given over
8 hours. To calculate the infusion rate when a pump will be
used, the nurse would ______________________ to obtain the
mL/hour.
d. divide 1000 mL D5 ½ NS by 8 hours
“… a nurse receives an order for 1000 mL D5 ½ NS to be given over
8 hours. To calculate the infusion rate, the nurse would input the
following:
1000 mL D5 ½ NS = 125 mL/hour
8 hours”
23. The size of the drip set may range from a mini-drip set to a
regular drip set. A mini-drip set has a gtt factor (drops per
minute) of
c. 60 gtts/mL.
“The size of the drip set may range from a mini-drip set, which has a
gtt factor of 60 gtts/mL, to a regular drip set, which has a rate of 1020 gtts/mL.”
24. A nurse receives an order for Ancef, with the dose in a 50 mL
solution, which must be given over 30 minutes. The gtt factor is
20 gtts/mL. The nurse uses the following calculation:
d. 50 mL x 20 gtt ÷ 30 minutes = 33.3 gtts/minute.
“… a nurse receives an order for Ancef, with the dose in a 50 mL
solution, which must be given over 30 minutes. The gtt factor is 20
gtts/mL. The nurse uses the following calculation:
50 mL x 20 gtt = 33.3 gtts/minute
30 minutes”
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
91
25. True or False: Before administration of certain intravenous
medications, the clinician should be familiar with all possible
effects of all drugs.
b. False
“Ideally, the clinician should be familiar with common drug
interactions associated with certain intravenous medications before
administration. While it is not possible to know all possible effects of
all drugs, referencing potential interactions and spacing the timing of
drug administration, when possible, can decrease the potential for
these effects. This also includes familiarity with each drug’s time of
onset, duration, and half-life, and what type of IV solution is
compatible for administration. By utilizing reference guides, checking
with other personnel, and using medical equipment appropriately,
the clinician can safely administer intravenous medications that will
be of great benefit to the patient.”
26. Oral medications are not as commonly administered in critical
care environments when compared to intravenous drugs
because
b. many critically ill patients do not have the ability to swallow oral
tablets.
“Oral medications are not as commonly administered in critical care
when compared to intravenous drugs; many critically ill patients do
not have the ability to swallow oral tablets or cannot tolerate
ingestion and absorption of these drugs from the gastrointestinal
tract. However, in the right circumstances, giving medications by
mouth can be one of the easiest ways to administer drugs. There are
some clinicians who believe that the oral route of administration is
not as effective when compared to IV drugs. However, there are
some medications that are only available through the oral route and
that cannot be given any other way; drugs used to treat
hyperlipidemia, such as atorvastatin, are some such examples.
Further, if an orally administered drug is able to achieve the same
tissue distribution as that of an intravenous drug, an oral medication
is no less effective than the same kind of drug given via a different
route. Although the route of oral administration requires an
additional step of absorption to reach systemic circulation, the oral
preparation is not necessarily less effective than other routes;
instead, it may simply take longer to exert its effects.”
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
92
27. _________________ typically act as sedative-hypnotics in the
central nervous system in response to GABA receptors.
c. Benzodiazepines
“Benzodiazepines typically act as sedative-hypnotics in the central
nervous system in response to GABA receptors.”
28. Benzodiazepines are often administered to patients in critical
care to control
c. pain and distress.
“Benzodiazepines are often administered to patients in critical care
because of the pain and distress that is often involved with care in
these areas. Critically ill patients often undergo painful and
frightening procedures and may be more likely to suffer from anxiety
and pain as a result…. One contraindication that is common to most
benzodiazepines is that these drugs should not be given to anyone
with a history of glaucoma. People who have narrow-angle glaucoma
or untreated open-angle glaucoma should not be given
benzodiazepines, as the drugs may increase intraocular pressure.”
29. Lorazepam is a benzodiazepine that has been shown
a. to be beneficial in controlling seizure activity.
“Lorazepam also acts as a central nervous system depressant in that
it causes sedation but does not necessarily impact the cardiovascular
system. Lorazepam has been shown to be beneficial in reducing
anxiety, promoting sedation, and controlling seizure activity…. Like
midazolam, there may be an increased risk of delirium with use of
lorazepam, and patients who have been given this drug should also
be monitored for signs of excessive sedation.”
30. True or False: Splitting tablets to administer one-half of a dose
is a relatively common practice but it also increases the risk of
errors.
a. True
“Splitting tablets to administer one-half of a dose is a relatively
common practice but it also increases the risk of errors. When
dividing doses by splitting tablets, the provider should note whether
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
93
the drug is safe for splitting, as noted on the packaging, and whether
it is scored on the tablet. The nurse should use a pill splitter to divide
the dose, which is the most accurate method of breaking the pill in
half.”
31. Which of the following benzodiazepines, used in critical care,
has a half-life of up to 120 hours?
d. Diazepam
“Another GABA agonist benzodiazepine that may be used in critical
care is diazepam has a half-life of up to 120 hours.”
32. ____________ is a sedative-hypnotic medication that is most
commonly used to induce anesthesia during surgery.
b. Propofol
“Propofol (Diprivan®) is a sedative-hypnotic medication that is most
commonly used to induce anesthesia during surgery;…”
33. ____________________ are a type of antipsychotic medication
that may be administered for the management of various
conditions, including acute psychosis or confusion.
d. Butyrophenones
“Butyrophenones are a type of antipsychotic medication that may be
administered for the management of various conditions, including
acute psychosis or confusion.”
34. When propofol is administered intravenously
a. its effects begin within approximately 40 seconds.
“The effects of propofol begin within approximately 40 seconds after
it has been administered intravenously. It has a half-life of 1 to 3
minutes, which means that it may be administered either on a
continuous basis throughout a procedure or additional doses must be
given in order to maintain its effects…. Propofol can have a
significant impact on the cardiovascular and respiratory systems.
Patients who receive propofol can be at risk of decreased oxygen
saturations, increased carbon dioxide levels, and hypotension, which
may occur before an overall decrease in cardiac output. These effects
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
94
are aggravated further when propofol is given with another drug that
affects hemodynamics, such as with analgesic drugs.”
35. True or False: Historically, haloperidol has been a first choice of
treatment of ICU delirium, however, it does carry an increased
risk of adverse effects, some of which could be life-threatening.
a. True
“Historically, haloperidol has been a first choice of treatment of ICU
delirium, however, it does carry an increased risk of adverse effects,
some of which could be life-threatening.”
36. _________________ are the first-line drug of choice to treat
non-neuropathic pain in critically ill adult patients.
c. Opioid analgesics
“Opioid analgesics are the first-line drug of choice to treat nonneuropathic pain in critically ill adult patients.”
37. Which of the following opioid analgesics is not recommended in
critically ill patients because of its risks of causing
neurotoxicity?
b. Meperidine
“Other examples of opioid analgesics that may be considered for use
in critically ill patients include hydromorphone, methadone, and
remifentanil hydrochloride (Ultiva®). Note that the administration of
meperidine is not recommended in critically ill patients because of its
risks of causing neurotoxicity.”
38. ______________________ is a vasopressor medication most
commonly administered for the control of blood pressure and
prevention of hypotension.
d. Dopamine hydrochloride
“Dopamine hydrochloride is a vasopressor medication most
commonly administered for the control of blood pressure and
prevention of hypotension.”
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
95
39. Another element that must be considered with ____________
administration is its lipophilic tendencies, in that it has the
potential to accumulate in the adipose tissue of the patient.
c. propofol
“Another element that must be considered with propofol
administration is its lipophilic tendencies, in that it has the potential
to accumulate in the adipose tissue of the patient, particularly when
it is administered over a longer period of time.”
40. ________________is a beta-blocker medication that is
primarily used for the treatment of severe hypertension.
b. Labetalol
“Labetalol is a beta-blocker medication that is primarily used for the
treatment of severe hypertension. It is an adrenergic receptor
antagonist that blocks the actions of alpha-1 as well as betaadrenergic receptors.”
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
96
References
The References below include published works and in-text citations of
published works that are intended as helpful material for your further
reading.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Physician’s Desk Reference (2017). Retrieved online at
http://www.pdr.net/browse-by-drug-name.
Le, J. (2016). Overview of pharmacokinetics. Retrieved from
http://www.merckmanuals.com/professional/clinicalpharmacology/pharmacokinetics/overview-of-pharmacokinetics
Marini, J., Wheeler, A. (2010). Critical care medicine: the essentials.
Philadelphia, PA: Lippincott Williams & Wilkins
UNC Eshelman School of Pharmacy. (2017). Intramuscular. Retrieved
from http://pharmlabs.unc.edu/labs/parenterals/intramuscular.htm
Spruill, W., Wade, W., DiPiro, J., Blouin, R., Pruemer, J. (2014).
Concepts in clinical pharmacokinetics (6th ed.). Bethesda, MD: ASHP
Hedaya, M. (2012). Basic pharmacokinetics (2nd ed.). Boca Raton, FL:
Taylor and Francis Group
Rosenbaum, S. (Ed.). (2017). Basic pharmacokinetics and
pharmacodynamics: an integrated textbook and computer simulations
(2nd ed.). Hoboken, NJ: John Wiley & Sons, Inc.
Rolfe, V. (2013). Metabolism.
http://www.nottingham.ac.uk/nmp/sonet/rlos/bioproc/liverdrug/
Edward, K. (2015). Why nurses need to know about pharmacokinetics
and pharmacodynamics – informing practice towards better medication
competence. Retrieved from
http://journalofadvancednursing.blogspot.com/2015/10/why-nursesneed-to-know-about.html
Jancova, P., Siller, M. (2012). Phase II drug metabolism, Topics on
Drug Metabolism, Dr. James Paxton (Ed.)., InTech, DOI:
10.5772/29996. Retrieved from
http://www.intechopen.com/books/topics-on-drug-metabolism/phaseii-drug-metabolism
Reade, M., Finfer, S. (2014). Sedation and delirium in the intensive
care unit. The New England Journal of Medicine 370: 444-454.
Retrieved from
http://www.nejm.org/doi/full/10.1056/NEJMra1208705#t=article
Nickson, C. (2016). Sedation in ICU. Retrieved from
http://lifeinthefastlane.com/ccc/sedation-in-icu/
Coviden. (2015). Sedation: tools for assessment. Boulder, CO:
Coviden AG
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
97
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
American College of Emergency Physicians. (2011). Sedation in the
emergency department. Retrieved from
https://www.acep.org/Content.aspx?id=75479
Jevon, P., Ewens, B. (2012). Monitoring the critically ill patient (3rd
ed.). West Sussex, UK: John Wiley & Sons
From New to ICU. (2016). How to perform train of four monitoring.
Retrieved from http://fromnewtoicu.com/blog/2016/3/11/train-of-four
O’Connor, D., Gwinnutt, C. (n.d.). Pharmacology of neuromuscular
blocking drugs and anticholinesterases. Retrieved from
http://www.anaesthesiauk.com/documents/PharmacologyNMBDsandA
nticholinesterasesFinal.pdf
Price, D., Kenyon, N., Stollenwerk, N. (2012). A fresh look at
paralytics in the critically ill: real promise and real concern. Annals of
Intensive Care 2: 43. Retrieved from
https://annalsofintensivecare.springeropen.com/articles/10.1186/2110
-5820-2-43
Zhou, C., Wu, L., Ni, F., Ji, W., Wu, J., Zhang, H. (2014). Critical
illness polyneuropathy and myopathy: a systematic review. Neural
Regen Res. 9(1): 101-110. Retrieved from
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4146320/
McLean, D., Diaz-Gil, D., Farhan, H., Ladha, K., Kurth, T., Eikermann,
M. (2015). Dose-dependent association between intermediate-acting
neuromuscular-blocking agents and postoperative respiratory
complications. Anesthesiology, Vol 122, 1201-1213. Retrieved from
http://anesthesiology.pubs.asahq.org/article.aspx?articleid=2278676
Rodrigues Nunes, R., Porto, V., Miranda, V., Quezado de Andrade, N.,
Carneiro, L. (2012). Risk factor for intraoperative awareness. Revista
Brasileira de Anestesiologia 62(3). Retrieved from
http://www.scielo.br/pdf/rba/v62n3/en_v62n3a09.pdf
Hammerschmidt, M. (2014). Pressors and vasoactives. Retrieved from
http://icufaqs.org/
Drugs.com. (n.d.). Dopamine side effects. Retrieved from
https://www.drugs.com/sfx/dopamine-side-effects.html
Algozzine, G., Algozzine, A. Lilly, D. (2010). Critical care intravenous
drug handbook (3rd ed.). St. Louis, MO: Elsevier Mosby
American Society of Anesthesiologists. (2014). Statement on safe use
of propofol. Retrieved from http://www.asahq.org/
Davis Drug Guide.com. (n.d.). Morphine. Retrieved from
http://www.drugguide.com/ddo/view/Davis-DrugGuide/51518/all/morphine
Drugs.com. (2012). Sublimaze. Retrieved from
https://www.drugs.com/pro/sublimaze.html
National Safety Council. (2014). Opioid painkillers: how they work and
why they can be risky. Itasca, IL: National Safety Council
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
98
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
Drahl, C. (2014). How does acetaminophen work? Researchers still
aren’t sure. Chemical & Engineering News 92 (29): 31-32. Retrieved
from http://cen.acs.org/articles/92/i29/Does-Acetaminophen-WorkResearchers-Still.html
ICU Delirium and Cognitive Impairment Study Group. (n.d.). Assess,
prevent, and manage pain. Retrieved from
http://www.icudelirium.org/pain.html
Action, Q.A. (2011). Issues in Pain Therapies and Research. Atlanta,
Georgia.
ICU Delirium and Cognitive Impairment Study Group. (n.d.).
Behavioral Pain Scale (BPS). Retrieved from
http://www.icudelirium.org/docs/behavioral-pain-scale.pdf
PDR.net. (n.d.). Propofol – drug summary. Retrieved from
http://www.pdr.net/drug-summary/diprivan?druglabelid=1719
Drugs.com. (n.d.). Isoproterenol. Retrieved from
https://www.drugs.com/ppa/isoproterenol.html
University of Illinois. (2013). College of Medicine at Chicago. Retrieved
from
http://chicago.medicine.uic.edu/UserFiles/Servers/Server_442934/Ima
ge/1.1/residentguides/final/icuguidebook.pdf.
Klabunde, R. (2012). Norepinephrine, epinephrine and acetylcholine –
synthesis, release and metabolism. Retrieved from
http://cvpharmacology.com/norepinephrine
PDR.org. (2017). Levophed. Retrieved online at
http://www.pdr.net/drug-summary/Levophed-norepinephrinebitartrate-868.
Hamadah, A., Newman, D., Mulpuru, S. (2014). Acute cardiogenic
shock after isoproterenol infusion for induction of atrial tachycardia.
The Journal of Innovations in Cardiac Rhythm Management, 5 (2014),
1512-1514.
Claris Life Sciences. (2011). Norepinephrine bitartrate injection, USP.
Retrieved from
http://www.us.clarislifesciences.com/pdf/Norepinephrine/Norepinephri
ne-Injection-USP-Package-Insert.pdf
Bai, X., et al. (2014). Early versus delayed administration of
norepinephrine in patients with septic shock. Critical Care 18: 532.
Retrieved from
https://ccforum.biomedcentral.com/articles/10.1186/s13054-0140532-y
ACLS Algorithms.com. (2016). ACLS and epinephrine. Retrieved from
https://acls-algorithms.com/acls-drugs/acls-and-epinephrine/
Cyriac, J., James, E. (2014). Switch over from intravenous to oral
therapy: a concise overview. J Pharmacol Pharmacother. 5(2): 83-87.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
99
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
Retrieved from
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4008927/
Coe College. (n.d.). Calculating flow rate formulas. Retrieved from
http://www.public.coe.edu/departments/Nursing/psychomotorskills/cal
culatingflowrateformula.htm
Stoelting, R., Hines, R., Marschall, K. (2012). Stoelting’s anesthesia
and co-existing disease (6th ed.). Philadelphia, PA: Elsevier Saunders
Erstad, B. (n.d.). Special caveats of drugs used in critical care
medicine, CCM Handbook, McGovern Medical School. Retrieved from
https://med.uth.edu/anesthesiology/files/2015/05/Chapter-41Special-Caveats-of-Drugs-Used-in-Critical-Care-Medicine.pdf
Upchurch, J. (2010). Receptors and the autonomic nervous system.
Retrieved from https://www.ems1.com/airwaymanagement/articles/893632-Receptors-and-the-autonomic-nervoussystem/
Ari, A., Fink, J., Dhand, R. (2012). Inhalation therapy in patients
receiving mechanical ventilation: an update. Journal of Aerosol
Medicine and Pulmonary Drug Delivery 25(6): 319-332.
Ari, A. (2012). Aerosol therapy for ventilator-dependent patients:
devices, issues, selection & technique. Clinical Foundations. Retrieved
from http://www.clinicalfoundations.org/assets/foundations14.pdf
MannKind Corporation. (2016). Afrezza. Retrieved from
https://www.afrezza.com/
Ari, A. and Restrepo, R. (2012). Aerosol Delivery Device Selection for
Spontaneously Breathing Patients. AARC Clinical Practice Guidelines.
Retrieved online at
http://www.rcjournal.com/cpgs/pdf/aerosol_delivery_2012.pdf.
Drugs.com. (2015). Albuterol. Retrieved from
https://www.drugs.com/pro/albuterol.html
Drugs.com. (2016). Ipratropium. Retrieved from
https://www.drugs.com/pro/ipratropium.html
Hambrecht, R., Berra, K., Calfas, K. (2013). Managing your angina
symptoms with nitroglycerin. What about exercise? Circulation
127(22). Retrieved from
http://circ.ahajournals.org/content/127/22/e642
Elefteriades, J., Tribble, C., Geha, A., Siegel, M., Cohen, L. (2013).
House officer’s guide to ICU care: fundamentals of management of the
heart and lungs. Minneapolis, MN: Cardiotext Publishing, LLC
Ferreira, J., Mochly-Rosen, D. (2012). Nitroglycerin use in myocardial
infarction patients: risks and benefits. Circ J. 76(1): 15-21. Retrieved
from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3527093/
Drugs.com. (2016). Nitroglycerin sublingual tablet. Retrieved from
https://www.drugs.com/pro/nitroglycerin-sublingual-tablet.html
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
100
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
Global RPH. (2016). Vasodilators. Retrieved from
http://www.globalrph.com/vasodilators.htm#Nitroglycerin
Bersten, A., Soni, N. (Eds.). (2014). Oh’s intensive care manual (7th
ed.). Waltham, MA: Butterworth Heinemann
Drugs.com. (2016). Labetalol. Retrieved from
https://www.drugs.com/pro/labetalol.html
Jones, D. (2016). FASTtrack pharmaceutics dosage form and design
(2nd ed.). London, UK: Pharmaceutical Press
McAuley, W., Kravitz, L. (2012). Pharmacokinetics of topical products.
Dermatological Nursing 11(2): 40-44.
Le, J. (2016). Drug distribution to tissues. Retrieved from
http://www.merckmanuals.com/professional/clinicalpharmacology/pharmacokinetics/drug-distribution-to-tissues
Tantisira, K. and Weiss, S.T. (2017). Overview of Pharmacogenomics.
UpToDate. Retrieved online at
https://www.uptodate.com/contents/overview-ofpharmacogenomics?source=search_result&search=pharmacokinetics&
selectedTitle=1~150.
Shargel, L., et al. (2012) Applied Biopharmaceutics and
Pharmacokinetics, Sixth Edition. McGraw-Hill.
Colwell, C. and Moore, E. (2017). Initial evaluation and management
of abdominal gunshot wounds in adults. UpToDate. Retrieved online at
https://www.uptodate.com/contents/initial-evaluation-andmanagement-of-abdominal-gunshot-wounds-inadults?source=search_result&search=gunshot%20wound%20treatmen
t&selectedTitle=2~150.
Harro, J. (2004). Textbook of biological psychiatry. Appendix A.
Wilmington, DE: Wiley-Liss, Inc.
Kim, D., et al. (2016). Predicting unintended effects of drugs based on
off-target tissue effects. Biochemical and Biophysical Research
Communications 469(3): 399-404. Retrieved from
http://www.sciencedirect.com/science/article/pii/S0006291X15309645
Uetrecht, J., Naisbitt, D. (2013). Idiosyncratic adverse drug reactions:
current concepts. Pharmacol Rev 65: 779-808. Retrieved from
http://pharmrev.aspetjournals.org/content/pharmrev/65/2/779.full.pd
f
Khetarpal, S., Fernandez, A. (2014). Dermatological emergencies.
Retrieved from
http://www.clevelandclinicmeded.com/medicalpubs/diseasemanageme
nt/dermatology/dermatological-emergencies/
Smith, R. (2012). Understanding how diabetes affects patient response
to medications. Podiatry Today 25(10). Retrieved from
http://www.podiatrytoday.com/understanding-how-diabetes-affectspatient-response-medications
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
101
71.
72.
73.
74.
75.
76.
77.
78.
79.
80.
81.
Farinde, A. (2016). Overview of pharmacodynamics. Retrieved from
http://www.merckmanuals.com/professional/clinicalpharmacology/pharmacodynamics/overview-of-pharmacodynamics
Center for Substance Abuse Research. (2013). Benzodiazepines.
Retrieved from http://www.cesar.umd.edu/cesar/drugs/benzos.asp
Glenbrook South High School. (2010). Barbiturates. Retrieved from
http://ic.galegroup.com/ic/scic/ReferenceDetailsPage/DocumentToolsP
ortletWindow?displayGroupName=Reference&jsid=4b0d8077a9024293
7c08f7470cd4da34&action=2&catId=&documentId=GALE%7CCV2645
000006&u=gotitans&zid=919f2c975b5d714087fb9cb2f2dce0fd
Moore, G. and Pfaff, J. (2017). Assessment and emergency
management of the acutely agitated or violent adult. UpToDate.
Retrieved online at https://www.uptodate.com/contents/assessmentand-emergency-management-of-the-acutely-agitated-or-violentadult?source=search_result&search=sedation%20and%20antipsychoti
cs&selectedTitle=7~150.
Caro, D. (2016). Induction agents for rapid sequence intubation in
adults. Retrieved from http://www.uptodate.com/contents/inductionagents-for-rapid-sequence-intubation-in-adults
McGrane, S., Pandharipande, P. (2012). Sedation in the intensive care
unit. Minerva Anestesiologica 78(3): 369-80. Retrieved from
http://www.minervamedica.it/en/getfreepdf/L4zOpYpzi0tFJGArBOMFcc
DGwygIxB2C514tGhBQaRnU8v0aOMnmCTeoqvxyw%252FuvblX5Polas
%252Bo9hd8jRAfOaw%253D%253D/R02Y2012N03A0369.pdf
Sleigh, J., Harvey, M., Voss, L., Denny, B. (2014). Ketamine – more
mechanisms of action than just NMDA blockade. Trends in Anaesthesia
and Critical Care 4(2-3): 76-81. Retrieved from
http://www.sciencedirect.com/science/article/pii/S2210844014200062
NIH Medline Plus. (2011). Chronic pain: symptoms, diagnosis, &
treatment. Medline Plus 6(1): 5-6. Retrieved from
https://medlineplus.gov/magazine/issues/spring11/articles/spring11pg
5-6.html
Ayasrah, S., O’Neill, T., Abdalrahim, M., Sutary, M., Kharabsheh, M.
(2014). Pain assessment and management in critically ill intubated
patients in Jordan: a prospective study. Int J Health Sci 8(3): 287298. Retrieved from
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4257364/
Thiele, H., Ohman, E., Desch, S., Eitel, I., de Waha, S. (2015).
Management of cardiogenic shock. European Heart Journal 36(20):
1223-1230. Retrieved from
https://academic.oup.com/eurheartj/article/36/20/1223/2293258/Man
agement-of-cardiogenic-shock
Galeski, D. and Mikkelsen, M. (2017). Evaluation of and initial
approach to the adult patient with undifferentiated hypotension and
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
102
82.
83.
84.
85.
86.
87.
88.
89.
90.
91.
92.
shock. UpToDate. https://www.uptodate.com/contents/evaluation-ofand-initial-approach-to-the-adult-patient-with-undifferentiatedhypotension-andshock?source=search_result&search=hypovolemic%20shock&selected
Title=1~150.
Beloncle, F., Meziani, F., Lerolle, N., Radermacher, P., Asfar, P.
(2013). Does vasopressor therapy have an indication in hemorrhagic
shock? Ann Intensive Care 3(13). Retrieved from
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3691630/
Orlando Health Surgical Critical Care. (2011). Vasopressor and
inotrope usage in shock. Retrieved from
http://www.surgicalcriticalcare.net/Guidelines/Vasopressors%20and%
20Inotropes%20in%20Shock.pdf
Angus, D., van der Poll, T. (2013). Severe sepsis and septic shock.
New England Journal of Medicine, 369: 840-851. Retrieved from
http://www.nejm.org/doi/full/10.1056/NEJMra1208623#t=article
Society of Critical Care Medicine, European Society of Intensive Care
Medicine. (2013). Surviving Sepsis Campaign: international guidelines
for management of severe sepsis and septic shock. Retrieved from
http://www.survivingsepsis.org/SiteCollectionDocuments/ImplementPocketGuide.pdf
Pollard, S., Edwin, S., Alaniz, C. (2015). Vasopressor and inotropic
management of patients with septic shock. Pharmacy and Therapeutics
40(7): 438-442. Retrieved from
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4495871/
Mitra, J., Roy, J., Sengupta, S. (2011). Vasopressin: its current role in
anesthetic practice. Indian J Crit Care Med. 15(2): 71-77. Retrieved
from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3145307/
Cossu, A., et al. (2014). Vasopressin in hemorrhagic shock: a
systematic review and meta-analysis of randomized animal trials.
BioMed Research International (2014), Article ID 421291, 9 pages.
Retrieved from https://www.hindawi.com/journals/bmri/2014/421291/
Kruer, R., Jarrell, A., Latif, A. (2014). Reducing medication errors in
critical care: a multimodal approach. Clinical Pharmacology: Advances
and Applications 2014: 6 117-126.
U.S. Food and Drug Administration. (2016). Regulatory information.
Retrieved from
http://www.fda.gov/RegulatoryInformation/Guidances/default.htm
Drugs.com. (2016, Nov.). Midazolam injection. Retrieved from
https://www.drugs.com/pro/midazolam-injection.html
U.S. Food and Drug Administration. (n.d.). Ativan (lorazepam)
injection. Retrieved from
http://www.accessdata.fda.gov/drugsatfda_docs/label/2006/018140s0
28lbl.pdf
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
103
93.
94.
95.
96.
97.
98.
99.
100.
101.
102.
103.
104.
105.
106.
Glaucoma Research Foundation. (2016, Aug.). Types of glaucoma.
Retrieved from http://www.glaucoma.org/glaucoma/types-ofglaucoma.php
Global RPH. (2016). Intravenous dilution guidelines. Retrieved from
http://www.globalrph.com/propofol_dilution.htm
Loh, N., Nair, P. (2013). Propofol infusion syndrome. Contin Educ
Anaesth Crit Care Pain (2013) doi: 10.1093/bjaceaccp/mkt007.
Retrieved from
http://ceaccp.oxfordjournals.org/content/early/2013/02/20/bjaceaccp.
mkt007.full
Orlando Health Surgical Critical Care. (2011). Delirium management in
the ICU. Retrieved from
http://www.surgicalcriticalcare.net/Guidelines/delirium_2011.pdf
Drugs.com. (2016, Feb.). Haloperidol. Retrieved from
https://www.drugs.com/pro/haloperidol.html
Page, V., et al. (2013). Effect of intravenous haloperidol on the
duration of delirium and coma in critically ill patients (Hope-ICU): a
randomized, double-blind, placebo-controlled trial. The Lancet
Respiratory Medicine 1(7): 515-523. Retrieved from
http://www.sciencedirect.com/science/article/pii/S2213260013701668
Mayo Clinic. (2017). Nitroglycerin. Retrieved online at
http://www.mayoclinic.org/drugs-supplements/nitroglycerin-oralroute-sublingual-route/description/drg-20072863.
Corvallis, Oregon EMS. (n.d.). Droperidol. [Protocol]. Retrieved from
http://www.corvallisoregon.gov/emsprotocols/Pharmacology%20Section/Droperidol-Final.pdf
Barr, et al. (2013). Clinical practice guidelines for the management of
pain, agitation, and delirium in adult patients in the intensive care
unit. Critical Care Medicine 41(1): 263-306.
McKnight, L. (2013). Pain management: non-opioid medications.
Pharmacy Times. Retrieved from
http://www.pharmacytimes.com/publications/health-systemedition/2013/july2013/pain-management-non-opioid-medications
Drugs.com. (2014, Jun.). Dobutamine. Retrieved from
https://www.drugs.com/pro/dobutamine.html
Drugs.com. (2016, Jul.). Milrinone. Retrieved from
https://www.drugs.com/pro/milrinone.html
Ventetuolo, C., Klinger, J. (2014). Management of acute right
ventricular failure in the intensive care unit. Annals of the American
Thoracic Society 11(5): 811-822.
U.S. Food and Drug Administration. (2014). Highlights of prescribing
information: Revatio. Retrieved from
https://www.accessdata.fda.gov/drugsatfda_docs/label/2014/021845s
011,022473s004,0203109s002lbl.pdf
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
104
107. Marino, P. (2014). Marino’s the ICU book (4th ed.). Philadelphia, PA:
Wolters Kluwer Health
108. Drugs.com. (2016). Ephedrine sulfate injection. Retrieved from
https://www.drugs.com/pro/ephedrine-sulphate-injection.html
109. Tiziani, A. (2013). Harvard’s nursing guide to drugs (9th ed.).
Chatswood, NSW: Elsevier Australia.
110. Masjedi, M., Zand, F., Kazemi, A., Hoseinipour, A. (2014). Prophylactic
effect of ephedrine to reduce hemodynamic changes associated with
anesthesia induction with propofol and remifentanil. Journal of
Anaesthesiology Clinical Pharmacology 30(2): 217-221. Retrieved from
http://www.joacp.org/article.asp?issn=09709185;year=2014;volume=30;issue=2;spage=217;epage=221;aulast=
Masjedi
111. Ragland, J., Lee, K. (2016). Critical care management and monitoring
of intracranial pressure. J Neurocrit Care 9(2): 105-112. Retrieved
from https://www.e-sciencecentral.org/articles/?scid=SC000020342
112. Reeder, G. and Prasad, A. (2017). Clinical manifestations and
diagnosis of stress (takotsubo) cardiomyopathy. UpToDate. Retrieved
online at https://www.uptodate.com/contents/clinical-manifestationsand-diagnosis-of-stress-takotsubocardiomyopathy?source=search_result&search=broken%20heart%20s
yndrome&selectedTitle=1~63.
The information presented in this course is intended solely for the use of healthcare
professionals taking this course, for credit, from NurseCe4Less.com. The information is
designed to assist healthcare professionals, including nurses, in addressing issues
associated with healthcare.
The information provided in this course is general in nature, and is not designed to address
any specific situation. This publication in no way absolves facilities of their responsibility for
the appropriate orientation of healthcare professionals.
Hospitals or other organizations using this publication as a part of their own orientation
processes should review the contents of this publication to ensure accuracy and compliance
before using this publication.
Hospitals and facilities that use this publication agree to defend and indemnify, and shall
hold NurseCe4Less.com, including its parent(s), subsidiaries, affiliates, officers/directors,
and employees from liability resulting from the use of this publication.
The contents of this publication may not be reproduced without written permission from
NurseCe4Less.com.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
105