title: Unilateral negative pressure pulmonary edema during anesthesia with a laryngeal mask airway.
abstract: OBJECTIVE
  To present a case of unilateral pulmonary edema after upper airway obstruction.
  
  
  METHODS
  In a 21-yr-old man, anesthesia was induced with propofol and maintained with N2O/O2/isoflurane via an LMA. After being placed in the lateral position, he had an episode of upper airway obstruction while breathing spontaneously. Hypoxemia (SpO2 80-83%) refractory to the administration of oxygen (F1O2 1.0) ensued following relief of the obstruction. Chest X-ray showed edema of the dependent lung. Treatment consisted of placing the patient in the sitting position and supplemental oxygen. The situation resolved over a few hours.
  
  
  CONCLUSIONS
  If airway obstruction occurs in the lateral position, development of negative pressure pulmonary edema (NPPE) in the dependent lung is favoured by hydrostatic forces and possibly the elevated resting position of the dependent hemidiaphragm.
authors.affiliation: Department of Anaesthesia and Intensive Care, Cairns Base Hospital, Queensland, Australia. kellmat.interlog.com.
authors.forename: M
authors.initials: M
authors.lastname: Sullivan
mesh_terms: D000328:Adult; D000402:Airway Obstruction / Q000150:complications*; D000758:Anesthesia; D006801:Humans; D017214:Laryngeal Masks / Q000009:adverse effects*; D008297:Male; D011654:Pulmonary Edema / Q000209:etiology*