[Severe hyponatremia during transurethral resection of prostate].

We report a case of severe hyponatremia (Na 82 mEq x l(-1)) during transurethral resection of the prostate for benign prostatic hypertrophy. A 61-year-old man was managed with epidural anesthesia and intravenous propofol. Three percent sorbitol (Uromatic S) solution was used for irrigation fluid. The serum sodium level 1 and 3 hours after the start of operation was 103 mEq x l(-1) and 82 mEq x l(-1), respectively. One hour after cessation of propofol administration he did not wake up, although he responded to mechanical stimulation. Saline (1.7%) and sodium bicarbonate (8.4%) were infused. Thirteen hours after the operation, serum sodium level rose to 114 mEq x l(-1), and he opened the eyes on verbal commands. Twenty-eight hours after the operation, serum sodium level was 132 mEq x l(-1). Postoperative neurological deficit did not occur.