Comparison of Epidural Bupivacaine and Dexmedetomidine with Bupivacaine and Fentanyl for Postoperative Pain Relief in Lower Limb Orthopedic Surgery.

Context: Different trials have shown that multimodal analgesia through different techniques is associated with superior pain relief. Opioids as epidural adjunct to local anesthetics have been in use for long and α2 agonists are being increasingly used for same. The present study aims at comparing the hemodynamic, sedative, and analgesic effects of epidurally administered fentanyl and dexmedetomidine when combined with bupivacaine.

Aims: The aim of this study was to compare the efficacy of epidural dexmedetomidine with bupivacaine versus epidural fentanyl with bupivacaine for postoperative pain relief.

Subjects and Methods: In this ongoing randomized double-blind study, 70 patients with ASA physical status classes I and II of either sex between 20 and 60 years scheduled for lower limb orthopedic surgeries under epidural block were randomly divided into two Groups ( n = 35). After epidural block with 15 ml of 0.5% bupivacaine, Group I received 1 μg/kg of fentanyl and Group II received 1 μg/kg of dexmedetomidine. Onset and duration of sensory block, motor block, and time to request for the first postoperative analgesia were recorded.

Statistical Analysis Used: The statistical analysis was performed using SPSS (Statistical Package for the Social Sciences) Version 15.0 Statistical Analysis Software, Mann-Whitney U-test and Chi-square test.

Results: The time to achieve T10 sensory block was early in Group I (dexmedetomidine) (8.10 + 1.03 min) as compared to Group II (15.03 + 1.67 min). Onset of motor was earlier in Group I (15.10 + 1.49 min) as compared to Group II (22.77 + 1.41 min). In Group I (dexmedetomidine), the majority of patients required 2-3 rescue doses, while in Group II (fentanyl), the majority of patients required 3-4 rescue doses.

Conclusions: Dexmedetomidine seems to be a better alternative to fentanyl as an epidural adjuvant due to early onset of sensory anesthesia, prolonged postoperative analgesia, and lower consumption of rescue analgesia.