Reexpansion hypotension. A complication of rapid evacuation of prolonged pneumothorax.

Three cases of hypotension are described that followed rapid evacuation of persistent unilateral pneumothorax. Common features included the presence of a pneumothorax for approximately one week before treatment commenced and profuse unilateral reexpansion edema, a rising hematocrit reading, hypotension, and anuria after evacuation of the pneumothorax in spite of a relatively normal pulmonary capillary wedge pressure. In one case, cardiac output was measured and found to be low (1.54 and 1.65 L/min/sq m), with a pulmonary capillary wedge pressure of 10 to 14 mm Hg. Death due to cardiovascular collapse occurred in one patient; ischemic colitis, acute renal failure, disseminated intravascular coagulation, and ischemic necrosis of both humeral heads occurred in another. The cases presented and the literature reviewed suggest that cardiovascular compromise was the end result of the combined effects of intravascular volume depletion and myocardial depression.