Negative pressure pulmonary hemorrhage.

Negative pressure pulmonary edema, a well-recognized phenomenon, is the formation of pulmonary edema following an acute upper airway obstruction (UAO). To our knowledge, diffuse alveolar hemorrhage has not been reported previously as a complication of an UAO. We describe a case of negative pressure pulmonary hemorrhage, and we propose that its etiology is stress failure, the mechanical disruption of the alveolar-capillary membrane.