Effect of preanesthetic famotidine on gastric volume and pH

The effect of preanesthetic 20 mg of famotidine on gastric fluid volume and pH were studied in patients scheduled for elective surgery. One hundred and twenty-eight patients were divided into four groups-control, intravenous, intramuscular and oral with 32 patients in each group. Patients in placebo group received no famotidine and served as control. Patients in the intravenous and intramuscular groups were administered famotidine one hour before surgery. Patients in the oral group were administered famotidine the night before and on the morning of surgery. Gastric volume in the control group was 19.1 +/- 10.8 ml; in the intravenous group, 7.4 +/- 6.4 ml; in the intramuscular group, 7.3 +/- 6.9 ml; and in the oral group, 7.1 +/- 6.9 ml. Gastric pH was 3.4 +/- 2.3, 6.8 +/- 1.1, 6.9 +/- 1.6, and 6.7 +/- 1.2 in groups one through four, respectively. When compared to the control group, famotidine significantly decreased gastric volume and increased gastric pH. There were no statistical differences among the different modes of administration. No adverse effects were observed in this study. It is concluded that preanesthetic management of 20 mg of famotidine reduced the risk of acid aspiration pneumonitis.