PEEP (Positive end-expiratory pressure)

PEEP is an adjustment on mechanical respirators that keeps a constant pressure against the lungs and helps open the alveolar pathways in situations where the lungs are failing to function normally. The higher the pressure, however, the greater the danger that one of these pathways may rupture, leading to further, severe complications. There are a number of other potential complications of positive pressure ventilation besides barotrauma (injury to the lung as mentioned above), hemodynamic disturbance due to a decrease in venous return associated with the increase in intrathoracic pressure (decreased cardiac output, decreased blood pressure, decreased urine output), fluid retention (due to decreased renal perfusion and increased antidiuretic hormone), respiratory alkalosis, increased intracranial pressure (due to the elevated intrathoracic pressure), nutritional disturbance (due to not being fed), and nosocomial pneumonia.