Comparison of the Effect of Pre-operative Single Oral Dose of Tramadol and Famotidine on Gastric Secretions pH and Volume in Patients Scheduled for Laparoscopic Cholecystectomy.

OBJECTIVE: To evaluate and compare the effects of pre-operative single oral dose of tramadol and famotidine on gastric secretions pH and volume in patients electively scheduled for laparoscopic cholecystectomy. STUDY DESIGN: Randomized control trial. PLACE AND DURATION OF STUDY: Department of Anaesthesia, King Saud University Riyadh, Saudi Arabia, from August 2011 to June 2013. METHODOLOGY: Ninety adult, ASA-I and II patients scheduled for laparoscopic cholecystectomy were included in the study. Patients were randomly assigned to receive pre-operatively either placebo (Group-C, n=30), oral tramadol 100 mg (Group-T, n=30) or famotidine 40 mg (Group-F, n=30). After induction of general anaesthesia, gastric fluid was aspirated through orogastric tube. The gastric secretions volume and pH was measured using pH meter. RESULTS: There was no statistically difference between groups in age, weight and gender. The gastric secretions mean pH was 2.06 ± 0.22,2.04 ± 0.20, 5.79 ± 0.77 and volume was 0.59 ± 0.17, 0.59 ± 0.14 and 0.28 ± 0.16 ml/kg in Group-C, Group-T and Group-F respectively. There was a significant statistical difference in the mean pH values between Group-C vs. Group-F (p < 0.001) and Group-T vs. Group-F (p < 0.001). Statistically significant difference was also found in the mean gastric secretions volume between Group - C vs. Group-F (p < 0.001) and Group-T vs. Group-F (p < 0.001). There was no significant difference in the mean gastric fluid pH values (p=0.99) and mean gastric secretions volume (p=0.99) between Group-T and Group-C. CONCLUSION: As compared to famotidine, pre-operative single oral dose of tramadol was unable to elevate the desired level of gastric fluid pH (> 2.5) and decrease in gastric secretions volume (< 0.4 ml/kg).

Effect of single oral dose of tramadol on gastric secretions pH.

BACKGROUND: Tramadol is an atypical analgesic agent. It has been shown that intramuscular or intravenous injection tramadol is able to inhibit M3 muscarinic receptors. Tramadol is able to mediate smooth muscles contraction and glandular secretions. We have evaluated the effects of single oral dose of tramadol given preoperatively on gastric juices pH in patients electively scheduled for laparoscopic cholecystectomy. MATERIALS AND METHODS: Sixty adult, American Society of Anesthesiologist I and II patients scheduled for laparoscopic cholecystectomy were included in the study. Patients were randomly assigned to receive either placebo (n = 30) or oral tramadol 50 mg (n = 30). General anesthesia was induced using propofol, fentanyl and cisatracurium. After induction of anesthesia 5 ml of gastric fluid was aspirated through orogastric tube. The gastric fluid pH was measured using pH meter. RESULT: There was no significant difference in the pH between the groups. Gastric pH of the placebo and tramadol groups was 1.97 versus 1.98 (P = 0.092) respectively. CONCLUSION: Preoperatively single oral dose of tramadol was unable to elevate the desired level of gastric acid secretions pH (>2.5). This may be due to pharmacokinetic disparity between the analgesic and pH elevating properties of tramadol.