Dexmedetomidine as an Adjuvant to 0.25% Bupivacaine in Ultrasound Guided Femoral Nerve Block for Preoperative Positioning and Postoperative Analgesia in Patients Undergoing Elective Surgery for Fracture Shaft of Femur.

Background: Femur fracture causes excruciating pain and surgical repair is recommended. To obtain satisfactory patient co-operation in the perioperative period, various analgesics have been used. Femoral nerve block (FNB) provides an excellent alternative for analgesia in the perioperative period. Dexmedetomidine of up to 2 μg.kg^-1 has been used in FNB as adjuvants in lower limb surgeries.

Aims: The aim was to study the effect of addition of Dexmedetomidine to Bupivacaine in FNB on the comfort of positioning for subarachnoid block (SAB) and postoperative analgesia.

Materials and methods: Prospective, randomized, double-blind design was followed. Seventy American Society of Anesthesiologist I and II patients aged 18-70 years of either gender were randomly allocated into Group B (20 mL 0.25% Bupivacaine + 2 mL Normal Saline) and Group BD (received 20 mL 0.25% Bupivacaine + Dexmedetomidine 2 μg.kg^-1 diluted to 2 mL) for FNB. Numerical rating scale (NRS) was recorded before and after FNB and comfort of positioning graded. After 10 min, subarachnoid block (SAB) was administered. NRS was recorded postoperatively until 24 h.

Results: The comfort of positioning improved in both the groups after FNB but was statistically not significant when compared among the groups (P = 0.7). Duration of postoperative analgesia was significantly higher in the Group BD (741 min ± 97 min) compared to the Group B (440 min ± 45 min) (P = 0.001) and was statistically significant.

Conclusion: FNB improved the comfort of positioning for SAB, but the addition of Dexmedetomidine did not have any added advantages with respect to comfort of positioning. However, the addition of Dexmedetomidine significantly increased the duration of postoperative analgesia with minimal hemodynamic changes.