Negative Pressure Pulmonary Edema Following Foramen Magnum Decompression for Chiari Malformation Type I

A 57-year-old obese female presented with vagal and hypoglossal nerve pareses, and magnetic resonance imaging revealed Chiari malformation type I. Standard surgical treatment for Chiari malformation type I was successfully performed. However, immediately after the patient was extubated, she developed signs of upper airway obstruction and chest radiography revealed pulmonary edema. Her ventilation was assisted by maintaining positive end-expiratory pressure at 8 cmH_2O. Intravenous furosemide and hydrocortisone were administered. Her respiratory status improved 12 hours later, and she was extubated 3 days after the operation. Postextubational course was uneventful, and the patient was discharged 2 weeks after extubation. The initial neurological deficits had mostly disappeared by 10 months after the operation. This unusual case of negative pressure pulmonary edema indicates that obesity and lower cranial nerve paresis are further risk factors for pulmonary edema as a postextubational complication of surgical treatment.