Beneficial physiological effects of positive end expiratory pressure (PEEP) include which of the following?
1) Increased PaO₂ for given FiO₂
2) Increased lung compliance (C_L)
3) Decreased shunt fraction
4) Increased functional residual capacity

Question

Quizplus · Accepted Answer

1) Positive end expiratory pressure (PEEP) increases PaO2 for a given FiO2 by improving oxygenation through recruitment of collapsed alveoli and maintenance of open airways. 
2) PEEP increases lung compliance by reducing the elastic recoil pressure of the lung, and improving ventilatory mechanics. 
3) PEEP reduces the shunt fraction by reopening atelectatic alveoli, maintaining alveolar surface area, and improving ventilation/perfusion matching. 
4) PEEP increases functional residual capacity (FRC) by preventing alveolar collapse, reducing the risk of alveolar overdistension, and improving gas exchange.

Beneficial Physiological Effects of Positive End Expiratory Pressure (PEEP) Include