Analgesic and antacid properties of i.m. tramadol given before Caesarean section under general anaesthesia.

BACKGROUND: Intramuscular (i.m.) tramadol increases gastric pH during anaesthesia similar to famotidine. We investigated the antacid analgesic value of a single dose of i.m. tramadol given 1 h before elective Caesarean section performed under general anaesthesia.

METHODS: Sixty ASA I parturients undergoing elective Caesarean section were included in a randomized double-blind study. The patients were randomly allocated to receive i.m. tramadol 100 mg (n=30) or famotidine 20 mg (n=30) 1 h before general anaesthesia.

RESULTS: At the beginning and the end of anaesthesia, patients receiving tramadol had a median gastric fluid pH of 6.4, which was not significantly different from those treated with famotidine (median 6.3). The infant well-being, as judged by Apgar score, cord blood gas analysis, and neurobehavioural assessment showed no significant difference between the two groups. Nalbuphine consumption in the first 24 h after operation was reduced by 35% in the tramadol group. Pain intensity score on sitting and sedation were significantly greater in famotidine group up to 24 h after surgery. There was no significant difference in incidence and severity of nausea and vomiting between the two groups.

CONCLUSION: A single i.m. dose of tramadol is useful pre-treatment to minimize the risk of acid aspiration during operation, and in improving pain relief during 24 h after surgery.