[Negative pressure pulmonary edema: 3 case reports]

Negative pressure pulmonary edema is a complication, described since 1977, caused by upper airway obstruction in both children and adults. Although its aetiopathogeny is multifactorial, especially outstanding is excessive negative intrathoracic pressure caused by the forced spontaneous inspiration of a patient against a closed glottis, that causes high arteriole and capillary fluid pressures that favor transudation into the alveolar space The resulting pulmonary edema can appear a few minutes after the obstruction of the airway or in a deferred way after several hours. The clinical manifestations are potentially serious, but normally respond well to treatment with supplemental oxygen, positive pressure mechanical ventilation and diuretics. Diagnostic suspicion is important for acting promptly. We report three clinical cases with acute negative pressure pulmonary edema.