PEEP & CPAP 1. PEEP: recruits a certain number of collapsed alveoli increases FRC & increases compliance in the dependent are (lower lobe) of lung *compliance decreases in the non-dependent (upper lobe) area of the lung due to overdistention

PEEP & CPAP


1. PEEP
ANSW recruits a certain number of collapsed alveoli

increases FRC & increases compliance in the dependent are (lower lobe) of lung
*compliance decreases in the non-dependent (upper lobe) area of the lung due tooverdistention

2. Indications of PEEP
ANSW Refractory Hypoxemia (will not respond to supplementalO2)

Shunt of >30%
Atelectasis with decreased FRC decreased
compliance

Certain disease processes

3. Goals of PEEP
ANSW enhance tissue oxygenation
maintain PaO2 >60 & SpO2 at or >90% @ acceptable pHRecruit alveoli & maintain

Restore FRC

4. Initiating PEEP
ANSW FIO2 >.50PIP >35 cwp

is PaO2 still <6
ANSW then start to increase PEEP by 3-5 unt
ANSW

1. acceptable oxygenation achieved
2. unacceptable side effects occur
ANSW
decreased compliance decreased
cardiac functionbarotrauma

5. Levels of PEEP
ANSW Minimum "physiologic" 3-5moderate 5-15

maximum >15

Optimal - PEEP level which achieves maximum benefits with least side effects

6. Physiologic Effects of PEEP on
ANSW
ANSW PaO2 - upFRC - up
PaCO2 - down BP -
down


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, PEEP & CPAP
PvO2 - improves Intrapulmonary
shunt - downCardiac output - down
Ca-v O2 - down ICP -
up

Compliance - improves

7. ARDS causes
ANSW
ANSW decrease compliancedecrease FRC

increase PVR




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