Comparison of Acid Reducing Properties of Tramadol and Ranitidine Given Before Caesarean Section Under General Anesthesia

Aim: To test the hypothesis that the volume and pH of the gastric contents in patients pre-treated with Tramadol will be comparable to those patients treated with Ranitidine. Methods: Sixty ASA II parturients undergoing elective Caesarean section were included in a randomized double-blind study. The patients were randomly allocated to receive intramuscular tramadol 100mg (n=30) or ranitidine 50mg (n=30), 1 hour before general anaesthesia. Gastric contents were collected using blind gastric aspiration after induction and at the end of the procedure. Results: At the beginning and the end of anaesthesia, patients receiving tramadol had a mean gastric fluid pH of 3.5±1.7 after induction and before recovery, which was significantly different from those treated with ranitidine (mean 5.8±1.5). The infant well-being, as judged by APGAR score at 1st minute and at 5th minutes after delivery, showed significantly higher proportion of newborn with low APGAR at 1st minute with Tramadol as compared to Ranitidine. Nalbuphine consumption in first 12 hours after operation was reduced in the tramadol group. There was no significant difference in incidence and severity of nausea and vomiting between the two groups. Conclusion: In comparison with Ranitidine, the administration of Tramadol in patients undergoing elective Caesarean sections under GA resulted in significantly greater volume and acidity of the gastric contents, lower neonatal APGAR at 1st minute, reduced post operative opioid consumption.