Acute postobstructive pulmonary edema.

Pulmonary edema developing after the relief of upper airway obstruction has been reported in association with a variety of factors including laryngospasm, foreign bodies, and tumors. However, as the phrase "negative pressure pulmonary edema" suggests, markedly negative intrapleural pressure is the dominant mechanism for the genesis of pulmonary edema associated with upper airway obstruction. A review for anesthesia providers of this poorly recognized and often perplexing syndrome may help to reduce the occurrence of this potential complication and facilitate its treatment.