[Benzodiazepine poisoning in a neonate: clinical and toxicokinetic evaluation following enterodialysis with activated charcoal]

Abstract

Case report: A pregnant woman who was a regular user of anxiolytics was admitted to the maternity ward at 38 weeks and 4 days amenorrhea after a massive overdose of clorazepate dipotassium, a benzodiazepine. The exact quantity ingested was undetermined. The infant, born at 39 weeks, presented no spontaneous breathing and tracheal intubation was necessary in the delivery room. The neonatal blood concentrations of the clorazepate metabolites were very high at delivery (26 mg/l nordiazepam and 3.5 mg/l oxazepam) and showed little change over the next 5 days (16 mg/l nordiazepam and 2.1 mg/l oxazepam, with an apparent half-life of 168 h for nordiazepam and 160 h for oxazepam). By day 6, the infant was still dependent on ventilator support and enterodialysis was begun with repeated doses of activated charcoal (1 g/kg every 6 h by gastric tube). Treatment was continued for 5 days and a spectacular diminution in the serum concentrations of the two metabolites was noted on day 11: 1.5 mg/l nordiazepam and less than 0.1 mg/l oxazepam. The nordiazepam and oxazepam half-lifes were reduced to 42 h and 30 h respectively. The concomitant clinical improvement authorized the weaning from ventilation on day 12.

Conclusion: This is the first report of the use of enterodialysis to treat severe benzodiazepine poisoning in a neonate. Depuration of the toxin was accelerated and the duration of intensive care was shortened thanks to this technique.