ULTRASOUND GUIDED FEMORO SCIATIC NEEVE BLOCK FOR LOWER LIMB SURGERIES: COMPARISON BETWEEN CLONIDINE AND DEXMEDETOMIDINE WITH LEVOBUPIVACAINE

Abstract

Introduction: Peripheral nerve blocks are effective for postoperative pain management in lower limb surgeries. The addition of adjuvants to local anesthetics can enhance the quality and duration of analgesia. This study aimed to compare the efficacy and safety of clonidine versus dexmedetomidine as adjuvants to levobupivacaine in ultrasound-guided femoro-sciatic nerve blocks for lower limb surgeries. Methods: In this prospective, randomized, double-blind study, 90 ASA I-II patients scheduled for lower limb surgeries were randomly allocated into two groups. Group A (n=45) received levobupivacaine with clonidine (1 μg/kg), and Group B (n=45) received levobupivacaine with dexmedetomidine (1 μg/kg) for ultrasound-guided femoro-sciatic nerve blocks. Postoperative pain was assessed using Visual Analog Scale (VAS) scores at 0, 2, 4, 8, 12, and 24 hours. Secondary outcomes included hemodynamic parameters (heart rate, blood pressure), motor blockade (Bromage score), and side effects (bradycardia, hypotension, nausea/vomiting). Results: Demographic parameters were comparable between the groups. VAS scores were significantly lower in the dexmedetomidine group compared to the clonidine group at all time points (p<0.001). Bromage scores, indicating motor blockade, were significantly higher in the clonidine group at 2, 4, and 8 hours (p<0.001). The dexmedetomidine group had a significantly higher incidence of bradycardia (33.3% vs. 15.6%, p=0.050) and hypotension (26.7% vs. 4.4%, p=0.004). Systolic blood pressure was significantly lower in the dexmedetomidine group at 4 and 8 hours (p=0.009 and p=0.026, respectively). Mean arterial pressure showed significant differences at multiple time points with variable patterns. Conclusion: Dexmedetomidine provides superior analgesia compared to clonidine when used as an adjuvant to levobupivacaine in femoro-sciatic nerve blocks but is associated with a higher incidence of cardiovascular side effects. Clonidine results in more intense motor blockade with a more favorable cardiovascular profile. The choice between these adjuvants should be individualized based on patient characteristics and surgical requirements.