Comparative Evaluation of Epidural Dexmedetomidine Versus Fentanyl as Adjuvants to Bupivacaine in Thoracic Surgery: A Randomized Controlled Trial

Abstract Background: Thoracic surgery is associated with significant postoperative pain, often managed with epidural analgesia. This study compared the analgesic efficacy, sedation profile, opioid-sparing effect, and patient satisfaction of epidural dexmedetomidine versus fentanyl when used as adjuvants to bupivacaine. Methods: In this prospective, randomised, double-blind trial, 50 patients undergoing elective thoracotomy were allocated equally into two groups. Group A received epidural dexmedetomidine (50 μg) with 0.125% bupivacaine, while Group B received fentanyl (50 μg) with 0.125% bupivacaine. Primary outcomes included postoperative analgesic requirements and sedation scores. Secondary outcomes included haemodynamic parameters, numeric rating scale (NRS) for pain, and patient satisfaction over 24 h postoperatively. Results: Baseline characteristics were comparable between groups. Mean arterial pressure and heart rate decreased significantly from baseline in both groups; however, the heart rate remained lower in the dexmedetomidine group throughout the intraoperative period ( P < 0.05). Postoperatively, the dexmedetomidine group required significantly less morphine (0.08 ± 0.4 mg vs 0.88 ± 1.8 mg, P = 0.047) and exhibited lower NRS scores ( P = 0.001). Sedation scores were significantly higher with dexmedetomidine ( P = 0.001), and patient satisfaction was markedly improved ( P = 0.001). Side effect incidence was comparable, with no significant increase in hypotension, nausea, or vomiting. Conclusions: Dexmedetomidine, when used as an epidural adjuvant to bupivacaine in thoracic surgery, provides superior sedation and analgesia with reduced opioid use and improved patient satisfaction, without increasing adverse effects. It represents a valuable alternative to fentanyl in thoracic epidural analgesia.