[A case of diaphragmatic paralysis in a patient with diabetes mellitus after surgery in prolonged prone position].

A 56-year-old woman with diabetes mellitus was scheduled for bilateral kidney lithotomy. She was in the prone position for about seven hours during operation. At the end of operation, arterial blood gas analysis showed PaO2 64 mmHg and PaCO2 44 mmHg under 100% oxygen inhalation through a face mask, and the chest x-rays showed elevation of the right diaphragm. Her trachea was intubated again. The right diaphragm returned to the preoperative level by positive pressure ventilation on supine position. Hypoxemia disappeared when the patient was placed in the sitting position, and the trachea was extubated. The right diaphragm returned to the normal level on the 1st postoperative day, but hypoxia continued until the 6th postoperative day with the patient on supine position. We speculate that the diaphragmatic paralysis was caused by over-extension of the neck for a prolonged period, and that the patient might have been susceptible to nerve injury due to underlying diabetes mellitus.