Diclofenac-tramadol vs. diclofenac-acetaminophen combinations for pain relief after caesarean section

We compared the analgesic efficacy of diclofenac-acetaminophen combination with diclofenac-tramadol combination to optimize multimodal post-operative analgesia in women undergoing caesarean section.

In this randomized, double-blind, parallel-group controlled trial, 204 women undergoing caesarean section under spinal anaesthesia with bupivacaine received rectal suppository diclofenac 100 mg (8 hourly till 24 h) plus either intravenous acetaminophen (1 g 6 hourly) or tramadol (75 mg 6 hourly) post-operatively. The primary outcome measure was the summed pain intensities during the entire observation period, calculated as the sum of time-weighted pain intensity scores as an area under the curve (AUC). Secondary outcome was the use of rescue analgesic, administered if the patient's numeric rating scale (NRS) scores ≥  4.

The overall pain score for the entire observation period measured as AUC was significantly lower in the diclofenac-tramadol group. However, diclofenac-tramadol combination produced Bonferroni-corrected statistically significant lower NRS pain scores only on movement at 24 h. Rescue analgesic consumption was comparable between the groups (13% vs. 12%, P = 0.872). Overall, the pain scores were low in both of the groups across various time intervals (median NRS scores 0-2 for pain both at rest and on movement), indicating satisfactory pain control in both groups. Side effects were few and comparable, except nausea (significantly more in tramadol group than acetaminophen group, 15% vs. 2%, P = 0.001).

Both diclofenac-tramadol and diclofenac-acetaminophen combinations can achieve satisfactory post-operative pain control in women undergoing caesarean section. The diclofenac-tramadol combination was overall more efficacious but associated with higher incidence of post-operative nausea.