Effects of different combinations of H2 receptor antagonist with gastrokinetic drugs on gastric fluid pH and volume in children--a comparative study.

In a prospective double-blind randomized study, 100 American Society of Anesthesiologists classification I (ASAI) children (aged 2-8 years) were allocated randomly to receive 1 of the 5 different oral premedicant combination, 2 hours before surgery. Group I (control) received placebo premedication, group II (RM) received ranitidine 2 mg/kg-1 with metoclopramide 0.2 mg/kg-1, group III (RD) received ranitidine 2 mg/kg-1 with domperidone 0.3 mg/kg-1, group IV (FM) received famotidine 0.5 mg/kg-1 with metoclopramide 0.2 mg/kg-1, and group V (FD) received famotidine 0.5 mg/kg-1 with domperidone 0.3 mg/kg-1. After tracheal intubation, gastric fluid was aspirated and analyzed for pH and total fluid volume. In 9 patients there was no aspirate, hence they were excluded from the study. Eighteen children from the control group and none of the children from other groups had gastric pH < 2.5 and volume > 0.4 ml/kg-1 (p < 0.01). Mean gastric pH (> 5.16) in RM, RD, FM, and FD groups was significantly higher as compared to control group (1.83) (p < 0.01). Mean gastric volume was significantly lower in RM, RD, FM, and FD groups (< 0.24 ml/kg-1) as compared to control group (0.5 ml/kg-1) (p < 0.01). Famotidine was found to be more effective in increasing gastric pH (p < 0.01) and decreasing volume (p < 0.05) as compared to ranitidine. No difference was found between metoclopramide and domperidone in increasing gastric pH and reducing gastric volume.