[A case of metabolic acidosis and tetany after ileal neobladder replacement]

A 64-year-old man visited our hospital with the complaint of macrohematuria and bilateral hydronephrosis. He had undergone total cystectomy and ileal neobladder replacement under the diagnosis of muscle invasive bladder cancer (cT2bN0M0). Tetany due to hyperventilation syndrome appeared on postoperative day 42. Blood gas analysis showed metabolic acidosis (pH 7.260, pO2 148.1 mmHg, pCO2 20.7 mmHg, HCO3 9.1 mmHg, BE -16.0 mmol/l). His condition was immediately improved after a urethral catheter was placed and sodium bicarbonate was administered. After re-removal of the urethral catheter, however, hyperventilation syndrome recurred. He was discharged from the hospital with the urethral catheter placed.