Acute hypoxemia after repositioning of patient: a case report.

Hypoxemia occurred after induction of anesthesia and repositioning in a patient undergoing hip pinning. The patient had previously presented to the emergency department with multiple fractures and hemodynamic instability sustained in a motor vehicle accident. Three days after admission to the intensive care unit the patient remained intubated with respiratory insufficiency and had developed acute respiratory distress syndrome with marginal oxygen saturation. The patient was transported to the operating room for hip pinning, and anesthesia was induced with midazolam, fentanyl, vecuronium, and isoflurane. When the patient was turned to the left lateral position, oxygen saturation suddenly worsened from 94% to 78%, with Pao2 from arterial blood gas measured at 54 mm Hg. The patient was returned to the supine position, but despite maneuvers to improve oxygen saturation, the patient's saturation remained below 87% and pulmonary thromboembolism was suspected. However, other signs of pulmonary embolus such as hemodynamic deterioration and right ventricular dysfunction were not present. Chest radiographs demonstrated severe left lung atelectasis, and surgery was postponed. Upon return to the intensive care unit, fiberoptic bronchoscopy was performed, and a large mucous plug was removed from his left upper and lower lobes, with subsequent improvement of Pao2 to 77 mm Hg with an oxygen saturation of 94%.