Comparative study between Epidural Bupivacaine added to Dexmedetomidine versus Bupivacaine with Fentanyl for Postoperative Pain Relief in Lower Limb Orthopedic Surgery: Randomised Controlled Trial

Background: Epidural anesthesia is the best standard for pain relief during and after surgery for lower abdominal and limb procedures. Historically, fentanyl has been used as a supplement for epidural administration, meaning it has been given alongside a smaller quantity of local anaesthetic (LA) to obtain the same level of anaesthesia. When administered via the epidural route, dexmedetomidine, a new member of the alpha-2 agonist class, has several positive effects.
Objectives: This study aimed to evaluate and compare the effectiveness of epidural fentanyl and dexmedetomidine as supplementary agents to epidural bupivacaine in terms of block quality, duration of action, duration of postoperative analgesia, as well as intra-operative and postoperative problems.
Patients and methods: Sixty cases were enrolled in the study with a mean age of 32.58 ± 8.13 years, and were categorised according to their physical status by the American Society of Anesthesiologists (ASA). Patients in classes I and II were divided into two groups of equal size (n=30). Subjects in group I received a spinal injection of 1 g/kg dexmedetomidine and 15 ml of a 0.5% bupivacaine solution. Group II participants were administered a 15 ml solution containing 0.5% bupivacaine along with an epidural injection of fentanyl at a dosage of one μg/kg.
Results: After 5 minutes, group I had a significant increase in mean heart rate (HR) compared to group II. The average start of sensory and motor block, and the duration required to reach the highest level T10, were all significantly decreased in group I compared to group II. After 2 minutes, group I had a much higher mean score on the Bromage scale than group II had. When comparing groups, I and II, group I had much longer postoperative pain relief from their initial rescue analgesic dose.
Conclusion: Based on the findings of our study, it was determined that dexmedetomidine exhibited superior qualities as an epidural adjuvant compared to fentanyl. Specifically, dexmedetomidine demonstrated enhanced hemodynamic stability, prompt onset of action, establishment of sensory anaesthesia, prolonged postoperative analgesia, and reduced consumption of postoperative LA for epidural analgesia (EA).