Download Chelan- South Douglas CPAP Training PowerPoint July 2013

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Our Goal in the Field using CPAP
The Physiological Effects
Delivery Systems
Indications/Contraindications
• “Learn the Lingo”
– NIPPV – Non-Invasive Positive Pressure Ventilation
• Includes CPAP, BiPAP and BVM
– CPAP – Continuous Positive Airway Pressure
• What we are going to be using
– PEEP – Positive End Expiratory Pressure
• Used on Ventilators with Intubated PT’s
– BiPAP – Bi-Level Positive Airway Pressure
CPAP
BiPAP
• Continuous Pressure
• Same pressure during
exhalation and inhalation
• Continuous pressure
• Pressures are different
between inhalation and
exhalation
– 5cmH20 Exhal; 15cmH20 Inhal
• Used in field
• Uses simple device or
complicated
• Needs little monitoring
– Set it and forget it
• Cheaper than BiPAP
• Not commonly used in field
• No simple devices
• Needs monitoring of delivered
pressures
• Expensive
• Pressurized air that is continuously delivered
throughout the entire respiratory cycle
– Both inhalation and exhalation
– Similar when you stick your head out of a moving
car window at constant Speed
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Non-Invasive
Easily Applied
Easily Discontinued
Used on CHF, COPD, Asthma, Near Drownings,
and Pneumonia
• Still able to use with other medications
• Is a bridge to keep patient going until
medications begin having effect
• “Alternative” to ETT Intubation
– “Prospective randomized trials demonstrated 50%70% of patients with severe exacerbation of COPD and
who receive non-invasive ventilation can avoid being
intubated” 1
– “Paramedics can be trained to use CPAP for patients in
severe respiratory failure. There was an absolute
reduction in tracheal intubation rate of 30% and an
absolute reduction in mortality of 21% in
appropriately selected out-of-hospital patients who
received CPAP instead of usual care.” 2
– COPD patients who do get intubated often are
ventilator dependent for long periods
1 Consensus
Conference. Noninvasive positive pressure ventilation. Respiratory Care 1997; 42:364369
2 Out-of-hospital continuous positive airway pressure ventilation versus usual care in acute respiratory
failure: a randomized controlled trial. Thompson J, Petrie DA, Ackroyd-Stolarz S, Bardua DJ. Ann
Emerg Med. 2008 Sep;52(3):232-41, 241.e1. doi: 0.1016/j.annemergmed.2008.01.006. Epub 2008
• Redistributes lung fluids
• Reduces work of breathing
• Counteracts intrinsic PEEP
– (Pursed lip breathing)
• Improved lung compliance
• Reverses areas of Atelecatsis
– Collapsed aveoli
• Decreases Preload/Afterload
– Good for CHF Patients
• Decreased V/Q Mismatch
• Improves Gas exchange
• When ventilation and perfusion do not match
• Causes:
– Pulmonary Edema
– Pulmonary Embolism
– Pneumonia
– Dead space increase
• Upper lungs
– V>P
• Mid lungs
– V=P
• Lower lungs
– V<P
• Overall Avg: 80%
• Caused by enough ventilation, but not enough
perfusion
– Pulmonary Embolism
– Cardiac Arrest
– Hypovolemia
• Normal in dead space
– Ventilation,
but no capillaries
• Caused by enough perfusion, but not enough
ventilation
– Atelectasis
– Increased secretions
– Mucus plugging
– Bronchial intubation
• Also called shunt perfusion
• Hypothetical pressure of a gas were it to
occupy the same volume of space as the
mixture it is in.
– Air at sea level has a pressure of 1 atmosphere, or
760mmHg.
– Air is 21% O2
– The partial pressure of room air O2 is 760 x 0.21 =
159mmHg
• The differences in pressure between a higher
concentration of gas and a lower
concentration of gas is called a pressure
gradient
– Gasses of a higher partial pressure have a
tendency to move towards areas of lower
pressure, until equilibrium is reached.
– This pressure gradient is what causes O2 to enter
the blood, and CO2 to leave it.
• Since expired air is 16% O2, expired air O2 has
a partial pressure of 760mmHg x 0.16 =
121mmHg
– (Room air was 139mmHg)
• This difference between the partial pressure
of expired air and inspired air causes O2 from
room air to enter the blood where the partial
pressure is lower, moving towards equilibrium.
• So, how does this apply to CPAP?
– CPAP changes the pressure gradient!
– We measure CPAP pressures with cmH20
– 1 cmH20 = 0.735mmHg
– On a typical patient, a CPAP of 10cmH20 will
increase the partial pressure of O2 by ~2.25%
– This increase in pressure “forces” more oxygen
into the blood!
– Even though it might seem small, the clinical
significance can be all that is needed
• Increased Pressure in Airways
– Stenting open of airways that are at risk of
collapsing due to excess fluid
– Extends aveoli to prevent collapse during
expiration
• Causes greater surface area = more exchange
– Easier for the patient to breathe air in
– Maintains gas exchange
• Increased oxygen Levels
• Reduced work of breathing
• Reduced V/Q mismatch
• Indications – Severe respiratory distress from
the following:
– Pulmonary Edema (including from near
drownings)
– Asthma exacerbations not responding to normal
treatments
– COPD failing conventional treatments
– Pneumonia
• Don’t use CPAP when patient is
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Unconscious
Unable to cooperate or maintain their own airway
Hypotensive (<90mmHG)
Vomiting
Suspected Pneumothorax
Trauma
Facial abnormalities
Unable to maintain mask seal
Extreme caution in pulmonary fibrosis
• Every CPAP system will be different
1. Overall goal is to increase airway pressure and gas
exchange
2. Verbally coach patient, explain the procedure
3. Apply waveform capnography (ETCO2)
4. Apply CPAP with pressure of 5-10 cmH20
5. Coach and reassure the patient
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Watch for resistance and apprehension
Check for leaks around mask/face seal
6. Reassess lung sounds and vitals q 5 mins. at least
7. In line nebulizers can be administered at
same time as CPAP
8. Nitroglycerin may be administered by
momentarily lifting facemask
9. If patient continues to worsen consider
advanced airway measures
• CPAP may cause a drop in blood pressure due
to increased intrathoracic pressure
• Watch for GI distention, which may lead to
vomiting
• Patient may become claustrophobic or
unwilling to tolerate mask
– Can be overcome with coaching
• Proceed to advanced airway for patients with
worsening respiratory distress or decreasing
level of consciousness.
• Not for use in children <12 Y/O
• Advise receiving hospital of CPAP so they can
prepare
• Pulmonary Edema patients will improve
within minutes of administration
– “CPAP to Pulmonary Edema is like D50 to
Hypoglycemia”
• Visual inspection of chest wall movement
should demonstrate improved respiratory
excursion
– Bilateral chest wall movement, retractions, etc.
– The look and feel of “Look, listen, and feel”
• When to do what:
• Respiratory Distress – increased effort and
frequency of breathing in maintaining normal
O2 and CO2 in blood
• Respiratory Failure – inability to maintain
normal amounts of O2 and CO2 in blood
• Signs of Respiratory Distress:
– Tachypnea
– Tachycardia
– Accessory Muscle Use
– Decreased Tidal Volume
– Paradoxical Abdominal Motion
• CPAP can generally be used on these patients
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Declining tidal volume
Irregular/Gasping Breaths
Decline in LOC
CO2 levels will climb, reducing LOC
High CO2 lowers pH, causing acidosis
• CPAP can provide a patient adjunct to allow
medications to take effect – B2 agonists,
Steroids, etc.
• CPAP Reverses CHF induced pulmonary edema
• Is less invasive than ET Intubation
• Helps COPD patients avoid ventilator
dependency
• Fixes V/Q mismatch, opens airways, increases
O2 pressure gradient, etc.