EFFECTS OF INTRAVENOUS FAMOTIDINE ON GASTRIC-ACID SECRETION IN PATIENTS UNDERGOING CARDIAC-SURGERY

OBJECTIVE: To determine the effects of cardiopulmonary bypass and famo tidine on gastric acid secretion in adults undergoing cardiac surgery. DESIGN: Prospective, randomized, double-blind, placebo-controlled stu dy. SETTING: University teaching hospital. PARTICIPANTS: Eighteen pati ents undergoing elective cardiac surgery with cardiopulmonary bypass. MAIN OUTCOME MEASURES: Famotidine 20 mg or NaCl 0.9% placebo was admin istered intravenously following induction of anesthesia and placement of a nasogastric pH probe. A second dose was given 12 hours after surg ery in the intensive care unit. Gastric pH was measured continuously a nd gastric volume was measured every 4 hours for up to 24 hours after cardiopulmonary bypass. RESULTS: Following famotidine administration, pH increased by 43% within 45 minutes and remained above 5.5 throughou t the study period (p < 0.05 vs placebo and baseline). The gastric pH did not increase, but remained above 4.0 in most patients in the place bo group for up to 12 hours after cardiopulmonary bypass. Gastric volu mes were on average 24% lower in the famotidine group (p > 0.05). CONC LUSIONS: Gastric acid secretion is decreased during and for 12 hours a fter cardiopulmonary bypass. Perioperative administration of famotidin e suppresses gastric secretion in cardiac surgery patients.