Analgesic effect of perineural dexamethasone on transversus abdominis plane block: A randomised controlled trial at a tertiary hospital in Ghana

Background: Postoperative pain management remains a significant challenge after Caesarean delivery (CD), with many patients experiencing inadequate analgesia despite conventional methods. This is particularly concerning as uncontrolled pain can lead to increased opioid consumption, delayed recovery, and prolonged hospital stay. This study aimed to evaluate the analgesic efficacy of adding perineural dexamethasone to bupivacaine in ultrasound-guided transversus abdominis plane (TAP) blocks for patients undergoing CD under spinal anaesthesia. Materials and Methods: In this prospective, randomized, double-blind study, 99 patients scheduled for elective CD under spinal anaesthesia were randomly allocated into three equal groups (n=33). Each participant received a bilateral TAP block with one of the following: bupivacaine (0.25%) plus dexamethasone (8 mg) [Group D], bupivacaine (0.25%) alone [Group B], or 0.9% saline [Group S]. Outcomes included the time to first analgesic request, postoperative opioid consumption, pain scores based on the Numerical Rating Scale (NRS), and patient satisfaction. Results: A total of 92 patients completed the study. Group B showed a significantly longer duration before requesting analgesia compared to Group S (327.5 ± 98.7 vs. 256.5 ± 72.3 minutes; p = 0.023). The addition of dexamethasone in Group D further extended this duration (485.2 ± 143.0 minutes; p < 0.001). Both Groups B and D demonstrated a significant reduction in opioid consumption within the first 24 hours postoperatively compared to Group S (p < 0.001), with Group D requiring the least amount of opioids (p < 0.001). Conclusion: Adding dexamethasone to bupivacaine-based TAP blocks significantly improves postoperative analgesia and reduces opioid consumption following Caesarean delivery, compared to bupivacaine alone or saline. This combination provides a clinically relevant benefit, reducing 24-hour pethidine consumption by approximately 70% compared to control, suggesting its potential role in optimizing postoperative pain management and enhancing recovery outcomes.