Comparison of effect of intraperitoneal instillation of additional dexmedetomidine or clonidine along with bupivacaine for post-operative analgesia following laparoscopic cholecystectomy

BACKGROUND AND AIMS: Despite advances in minimally invasive surgery, postoperative pain remains a concern after laparoscopic cholecystectomy. This study aims to compare the effect of intraperitoneal instillation of bupivacaine with alpha-2 agonists (dexmedetomidine and clonidine) for postoperative analgesia. METHODS: One hundred and eight patients scheduled for elective laparoscopic cholecystectomy were randomised to receive either 20 mL of 0.5% bupivacaine (Group B), 20 mL of 0.5% bupivacaine with dexmedetomidine 1 μg/kg (Group BD) or 20 mL of 0.5% bupivacaine with clonidine 1 μg/kg (Group BC). Study drug made to equal volume (40 mL) was instilled before the removal of trocar at the end of surgery. Standard general endotracheal anaesthesia with intra-abdominal pressure of 12–14 mm Hg during laparoscopy was followed uniformly. The primary objective of our study was the magnitude of pain. One way analysis of variance (ANOVA) for continuous variables and Chi-square test for categorical variables was used. RESULTS: The Numerical Rating Scale (NRS) scores for pain intensity did not show any statistical significance at any of the pre-defined time points. Time to first request for analgesia was shortest in group BC (64.0 ± 60.6 min) when compared to the other groups (B, 78.8 ± 83.4 min; BD, 112.2 ± 93.4 min; P < 0.05). Total amount of rescue fentanyl given in groups BD (16.8 ± 29.0 μg) and BC (15 ± 26.4 μg) was significantly less than B (35.7 ± 40.0 μg); P < 0.05). CONCLUSION: The addition of alpha-2 agonists to bupivacaine reduces the post-operative opioid consumption, and dexmedetomidine appears to be superior to clonidine in prolonging time to first analgesic request.