Effects of oral nizatidine on preoperative gastric fluid pH and volume in children

Abstract

We have studied the effect of oral nizatidine 6 mg kg-1 in total on preoperative gastric fluid pH and volume in children. One hundred and four healthy children, aged 4-11 yr, were allocated randomly to four groups (n=26): placebo administered at 21:00 and 06:30 the night before and on the day of surgery, respectively (placebo-placebo: control); nizatidine 6 mg kg-1 at 21:00 and placebo at 06:30 (nizatidine-placebo); placebo at 21:00 and nizatidine 6 mg kg-1 at 06:30 (placebo-nizatidine); and nizatidine 3 mg kg-1 at 21:00 and 06:30 (nizatidine-nizatidine). Each child ingested a large volume of apple juice 3 h before estimated induction of anaesthesia. After induction of anaesthesia, pH and volume of gastric fluid obtained via an orogastric tube were measured. Mean pH in the placebo-nizatidine and nizatidine-nizatidine groups was significantly higher than that in the placebo-placebo group (5.7 (sem 0.3), 6.0 (0.3) vs 1.8 (0.2), respectively) (P<0.05). Mean pH in the nizatidine-placebo group was similar to that in the control group (2.3 (0.3) vs 1.8 (0.2)). The number of children with pH < 2.5 and volume > 0.4 ml kg-1 in the nizatidine-nizatidine (0%) and placebo-nizatidine (4%) groups was reduced compared with the control (46%) or nizatidine-placebo (38%) group. These data suggest that oral nizatidine 6 mg kg-1 in total, if given at one dose on the morning of the day of surgery or in two equal doses at bedtime before surgery and on the morning of surgery, may have a role in the prophylaxis of acid aspiration syndrome. Further studies are needed to determine the optimal dose and safety of the drug in children. © 1994 British Journal of Anaesthesia.