Positive end-expiratory pressure

Overview
Positive end-expiratory pressure (PEEP) is a term used in mechanical ventilation to denote the amount of pressure above atmospheric pressure present in the airway at the end of the expiratory cycle. The equivalent in a spontaneously breathing patient is CPAP. PEEP is set on the ventilator.

Physiology
PEEP improves gas exchange by preventing alveolar collapse, recruiting more lung units, increasing functional residual capacity, and redistributing fluid in the alveoli.

Indications
Hypoxemia due to the following:
 * ARDS
 * Pneumonia
 * Pulmonary edema
 * Atelectasis

Contraindications

 * Increased Intracranial Pressure
 * Pneumothorax that has not been treated
 * Bronchopleural fistula