Effect of PEEP on gas exchange, pulmonary mechanics, and hemodynamics in adult respiratory distress syndrome (ARDS).

The effect of positive end-expiratory pressure on a value resulting in maximum static effective compliance was studied in 13 artificially ventilated patients suffering from adult respiratory distress syndrome. Applying positive end-expiratory pressure in this manner resulted in improvement of oxygen delivery and left ventricular stroke work. In the patients with high venous admixture under zero end-expiratory pressure cardiac output increased but in those with moderate pre-existing venous admixture cardiac output decreased. We conclude that the response to positive end-expiratory pressure depends on the importance of the venous admixture. Artificial ventilation with positive end-expiratory pressure on a level resulting in maximum static effective compliance is indicated in cases with high venous admixture.