Download Megan CPR notes - DoveLewis | Emergency Animal Hospital

RECOVERing from CPR
Megan Brashear CVT, VTS (ECC)
Speaker Notes
The REassessment Campaign On VEterinary Resuscitation (RECOVER) Initiative was a
collaborative effort of over 80 veterinarian specialists in Emergency and Critical Care.
These specialists combed through both human and veterinary research to compose
consensus-based clinical CPR guidelines. Their recommendations are included in this
lecture.
The most important aspect of any emergency is being prepared. Not only should your
team have training but an area of the treatment floor should be designated to
emergencies/CPR. A crash cart should be stocked and ready to go. In most cases a tackle
box is appropriate and can be moved to the surgical suite or other areas of the hospital
where it may be needed. The crash cart should be checked daily and kept stocked at all
times. The emergency area should also have quick access to oxygen - either an
anesthesia machine or oxygen regulator. Running drills with your team will help the staff
feel comfortable in their roles and improve communication.
The key to any crash kit is ACTION above THINKING. Your crash kit should be organized
and pared down so that each area is not so overwhelming for use during an emergency.
It is also very important to prepare owners for a possible CPR event. While it rarely
happens, patients can arrest under anesthesia and the staff needs to know the owner’s
wishes before proceeding with CPR. Make sure to discuss options with owners (basic
CPR vs. open chest CPR vs. DNR) who leave their pets at the hospital for any reason.
Label the patients so it is easy for the staff to identify owner wishes and makes sure to
have phone numbers readily available.
In cases of illness, there are warning signs to impending patient arrest. Trust your gut
with these patients, as many technicians can ‘feel’ when something bad is about to
happen and are ready to act. Changes in mentation or a persistently dull mentation
should be closely monitored. Any change in respiratory pattern, rate, or depth is reason
for concern; especially if it happens without any external stimulation (temperature being
taken, recumbency changes, drugs administered). Any patient with weak or irregular
pulses is at risk for arrest, especially if they started somewhat normal and are trending
downwards. Hypotension also falls into this category – the body can compensate for a
period of time but these patients need blood pressure support as soon as it can be given.
Sudden tachy or bradycardia is immediate cause for concern – especially without external
stimulation. Sudden tachycardia can be a sign of respiratory distress and/or pain – be
sure to check for these conditions. Sudden bradycardia tends to continue to get worse so
it needs to be treated ASAP. Any patient with respiratory distress is in danger of going
into respiratory arrest and then CPA – keep a close eye on them and do what you can to
provide oxygen supplementation and sedation. Severe hypothermia (especially in cats)
can lead to arrest; these patients also must be monitored closely. In ANY emergency it is
important to take your own pulse first, take a deep breath and focus before proceeding.
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Triggers to start CPR in a patient include:
• Respiratory arrest – once an animal stops breathing full arrest isn’t far behind
• Agonal breathing patterns – while it may look like the patient is taking deep
breaths this is the deepest part of their brain stem desperately trying to keep
them alive – for all intents and purposes an agonal animal is dead.
• Non-ascultable heart beat – if you can’t hear it, it isn’t happening
• Non-palpable pulses – even in very sick patients there should be at least a faint
femoral pulse. If there is still a heart beat but no pulses the patient my not be in
full arrest but is certainly on their way and needs intervention
• Ventricular fibrillation on ECG – these patients are not longer circulating blood and
it is vital to treat this right away
Chest compressions are the most important duty in CPR. They should be started as soon
as arrest is recognized and continued throughout. These compressions are the only
means for oxygen to be carried to the brain and every time compressions are stopped the
brain is deprived of oxygen. When chest compressions are done correctly it is very tiring;
compression efficacy decreases dramatically over time, so don’t be a hero, switch out at
two minute intervals.
Chest compressions on cats are usually done with them in lateral recumbency. Cats have
a flexible ribcage and should be relatively easy to compress. You want to compress their
chest about 30% of its diameter and do 100-150 compressions a minute. Careful not to go
too fast, you want to give the heart time to refill before compressing it again.
Chest compressions in small dogs (<15#) are performed in lateral recumbency. Place the
palms of both hands over the heart (your fingers will be pointed towards the spine) and
compress with your palms. Again, compress about 30% of the chest diameter and do 100150 compressions a minute.
Chest compressions on large dogs (>15#) are commonly performed at the widest part of
the chest. There is no data to suggest that this is the ‘best’ hand placement, but it is how
compressions are commonly taught in large dogs. These dogs are designed with a lot of
tissue mass in their thoracic cavity and their hearts are too well-protected for you to be
able to compress them without using their chest mass to help. It works best to place
yourself at the spine of the dog, make sure you have some leverage (you want to be
higher than the dog so stand on a stepstool or kneel on the table next to the dog) and
place your hands at the widest part of the chest (halfway between sternum and spine –
closer to the abdomen than you think). You’ll need to lock your elbows and bend at the
waist with every compression using your body weight to compress the chest about 30%
of its diameter. You will need to do 100-150 compressions a minute. Everyone should be
trained to do chest compressions so that you can trade out every two minutes.
While compressions are started it is time to establish a patent airway. Obviously the
quickest and most simple way to achieve this is through orotracheal intubation.
Depending on the condition of the animal a tracheostomy may be necessary – be sure to
know the supplies needed and what is involved with this procedure just in case. If
possible, intubate the animal in lateral recumbency to allow for compressions to continue
and maintain as much cerebral perfusion as possible. Once the patient is intubated you
will need 100% oxygen ready – this can be achieved with an anesthesia machine or an
ambu-bag hooked up to an oxygen line. It is a good idea to have some sort of suction
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available in case there is blood or fluid in the airway, and some gauze and forceps ready
to clean out the oropharynx if necessary.
Once the patient is intubated, it is very important to secure the endotracheal tube as
soon as it is placed and to inflate the cuff. We need to be able to put pressure and hold
pressure in the lungs during CPR and if the cuff is not inflated all of the air pressure will
leak out of the lungs and your breaths will not be effective.
Once the patient is intubated and hooked up to 100% oxygen it is time to breathe for
them. Begin a rhythm of breathing at 10 breaths a minute. This seems abnormally slow,
especially with all of the adrenaline happening. There are a couple of important reasons
for this slow respiratory rate. When a patient experiences CPA the body hangs on to
oxygen – it is not using and releasing C02 like normal. Also, every time you breathe for
the patient it increases intrathoracic pressure which them decreases venous return and
lowers cardiac output. The more they breathe the less your compressions are helping.
Give them a breath every 6 seconds. If you are using an anesthesia machine be sure to
keep an eye on the pressure gauge. In most CPR cases the pressure should go to at least
20cm/H20 with each breath, talk with the DVM about increasing or decreasing that
pressure in the face of thoracic trauma. If you are using an ambu bag pay attention to the
compliance of the bag, if it is getting more difficult to squeeze the bag there may be a
pneumothorax or other condition that needs to be addressed.
IV access is an important part of circulation. Be careful not to assume that every patient
undergoing CPR needs a bolus of crystalloid fluids. Fluid overload can overfill the heart
and reduce cardiac output. Be sure to communicate with your DVM before starting a fluid
bolus. The jugular route is the best route for fluids and drugs during a CPR situation.
These medications have a direct line to the heart when given via the jugular route.
However, this is often the most challenging route when chest compressions are being
performed. If it is possible to place a jugular catheter without stopping compressions
then by all means place one! Be sure to secure it well (suture!). Next best is a peripheral
catheter. Hind legs are useless; the chances of drugs given through a saphenous catheter
reaching the heart during CPR are slim to none. Use the cephalic veins and make sure to
follow each drug with a 10-20ml bolus of saline or crystalloids and elevate the limb to let
gravity help deliver the drugs. Drugs can also be given intratracheal (IT) – the dose will
need to be adjusted (usually 10x normal dose for epinephrine) and suspended in sterile
water. Attach the syringe to a red rubber catheter and feed it down the ET tube. Drugs
are better absorbed endobronchial than via the trachea so feed the red rubber as far
down as possible and administer the drugs.
There are a variety of drugs that are kept in crash carts for various emergency situations,
the most important ones to use and be familiar with are epinephrine, atropine, and
naloxone.
• Epinephrine: Given every 3-5 minutes
Causes vasoconstriction increasing arterial pressure, improving perfusion to
the brain
0.01mg/kg IV; 0.1mg/kg IT
Watch for ventricular tachycardia post-arrest (side effect)
• Atropine: Use only if patient has a heartbeat
Increases heart rate (intense vagal stimulation)
0.5ml/10# IV
• Naloxone: Reversal for opioids. Should be given in any anesthetic arrest.
0.1 mg/kg IV
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Anesthetic arrest can happen and it allows for the best chance to revive the patient if it is
caught quickly enough. Use your monitors but don't rely solely on them. Use an
esophageal stethoscope that will allow you to quickly determine patient decline vs.
equipment malfunction.
We will briefly discuss open chest CPR as some clients wish this for their pets. Open
chest CPR involves cutting through the thoracic wall, spreading the ribs apart and
performing internal cardiac massage. This is the preferred method for many trauma cases
or if there is known thoracic trauma. If closed chest CPR has yielded no results after 5
minutes then open chest should be discussed. There is little time to prep but the lateral
thoracic cavity should be clipped and quickly cleaned. A scalpel blade is used to cut
through skin and muscle. Rib retractors or an assistant will be needed to hold open the
ribs and the DVM, wearing sterile gloves, will reach in and begin massaging the heart.
This is also a good option for anesthetic deaths, especially if the surgeon is already sterile
and in the abdominal cavity; it is simple for them to cut through the diaphragm and begin
cardiac massage.
Once you have started CPR it is important to evaluate your patient’s vital signs and
watch for changes for better or worse. Use whatever monitors you can – the
multiparameter monitors for anesthesia work great in these cases. This allows for
watching the ECG, monitoring Sp02, ETC02, body temperature, etc. If you stop
compressions to check for an ECG rhythm make sure to not stop for longer than 10
seconds. You can stop respirations for 20-30 seconds to see if they will breathe on their
own.
Run drills with your team, and be sure to include all members of the team.
Communication is important in a CPR situation so that everyone knows what everyone
else is working on. While CPR in many situations may be unsuccessful, the training and
practice is worth it for those that return home to their owners.
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