[Withdrawal syndrome in a critically ill child after sedation with midazolam and fentanyl].

A 7-year-old girl suffered from withdrawal syndrome with systemic convulsion after sedation with midazolam and fentanyl. She had a history of severe accidental alkaline esophagitis, and under went polysurgeries. This time, she was scheduled to receive reconstruction of the esophagus with small intestine in order to resolve esophageal stenosis. Operation and anesthesia lasted for 14 hours, and 17 hours, respectively. In the postoperative period, she was under heavy sedation with midazolam and fentanyl in order to keep neck position immobile. Her sedation persisted for 14 postoperative days, and the total doses of midazolam and fentanyl were more than 100 mg x kg(-1), and 6.4 mg x kg(-1), respectively. Thereafter, her sedation was tapered and discontinued within about 24 hours. After 12 hours, she suddenly developed systemic convulsion with loss of consciousness. There was no evidence of obvious organic central nervous system abnormality. We suspected withdrawal syndrome, and gradual decrease of midazolam and fentanyl prevented her from going into withdrawal syndrome. We have to pay attention to withdrawal syndrome when heavy and long sedation with midazolam and fentanyl was employed and the drugs were then tapered and discontinued.