Analgesic Efficacy of Transverse Abdominal Plane Block after Elective Cesarean Delivery - Bupivacaine with Fentanyl versus Bupivacaine Alone: A Randomized, Double-blind Controlled Clinical Trial.

BACKGROUND: The analgesic benefit of transversus abdominis plane (TAP) blocks for cesarean delivery remains controversial. In our study, we compared the analgesic efficacy of TAP block using local anesthetic bupivacaine and adjunct fentanyl with bupivacaine alone in patients undergoing elective cesarean section.

METHODS: Our study was a randomized, double-blind, controlled clinical trial where sixty patients undergoing elective cesarean delivery under subarachanoid block (2 ml of 0.5% bupivacaine) were randomized into two groups, A and B. At the end of the surgical procedure, bilateral TAP block was performed guided by the ultrasound. Group A received 38 ml of 0.25% bupivacaine and 2 ml of 50 μg of fentanyl, whereas Group B received 38 ml of 0.25% bupivacaine + 2 ml of normal saline. The total volume was divided equally and administered bilaterally. Each patient was assessed for 24 h after TAP block, for time to rescue analgesia, pain using visual analog scale (VAS) score at rest and on movement, hemodynamic parameters (heart rate and blood pressure), nausea, vomiting, and sedation. Diclofenac 75 mg was given as rescue analgesia when the patient complained of pain or when VAS score >4.

RESULTS: Prolonged postoperative analgesia was noticed with both the groups, with a mean time to rescue analgesia of approximately 6.5 h. There was no significant difference in time to rescue analgesia (6.49 ± 0.477 vs. 6.5 ± 0.480) when both the groups were compared among themselves. The pain scores among the two groups when compared did not show any added benefit. Incidence of nausea, vomiting, and sedation when compared between both the groups showed no difference.

CONCLUSION: The TAP block as a part of a multimodal analgesic regimen definitely has a role in providing superior analgesia in the postoperative period. However, adjunct fentanyl to local anesthetic bupivacaine was found to have no added advantage when quality and duration of analgesia was compared.