PEEP in prone

Q: What is the implication of Positive End Expiratory Pressure (PEEP) in patients with a prone position?



Answer: 

The teaching point of this pearl is to emphasize the point that supraphysiologic applied PEEP (i.e.,>5) is usually nor helpful, rather may be harmful, in patients in prone position. 

In a regular ventilated patient who stays in the supine position, PEEP increases the blood flow to the dorsal portion of the lungs. It helps in maintaining a ventilation-perfusion (V/Q) mismatch. But when patients are put in a prone position, PEEP increases the blood flow to the ventral portion of the lungs which is out of proportion to the redistribution of ventilation, thereby exacerbates the V/Q mismatch.

#pulmonary


Reference:

Petersson J, Ax M, Frey J, et al. Positive end-expiratory pressure redistributes regional blood flow and ventilation differently in supine and prone humans. Anesthesiology 2010; 113:1361.