Randomized control study to evaluate the effect of adding Dexmedetomdine to levobupivacaine in femoral sciatic block in total knee replacement

Abstract

Background In recent years there has been an increasing interest in the practice of regional anesthesia especially peripheral nerve blocks for surgical anesthesia and postoperative analgesia. Imaging guidance for nerve localization helps the promise of improving block success with fewer complications. Among the imaging modalities available nowadays, ultrasonography seems to be the most suitable for regional anesthesia. One the most significant advantage of ultrasound (US) technology is the availability to provide anatomic examination of the area of interest. Aim The aim of this study is to evaluate the additive effect of dexmedetomidine to levobupivacaine in femoral sciatic block in total knee replacement regarding the onset and duration of both sensory and motor blockade, postoperative analgesia requirements. Patients and methods After ethical approval, 60 patients aged 45–65 years old, with an American Society of Anesthesiologists (ASA) physical class I and II who underwent total knee replacement using combined femoral-sciatic nerve block, were included in this prospective, randomized, controlled, double-blinded study. Patients were randomly assigned to receive levobupivacaine alone (group B) or dexmedetomidine 100 µg added to levobupivacaine (group BD) [n=30 patients for each group] for combined femoral-sciatic nerve block. Results This study showed that the addition of dexmedetomidine 100 µg to levobupivacaine during ultrasound-guided combined femoral-sciatic nerve block for total knee replacement was associated with, −20% shorter onset times for sensory and motor block, −25% faster time for surgical readiness, and longer duration of sensory and motor block (+45% and +40%, respectively) and +50% longer duration of analgesia. Conclusion Addition of dexmedetomidine to levobupivacaine during combined femoral-sciatic nerve block for total knee replacement was associated with faster onset of sensory and motor block, decrease intraoperative and postoperative requirements of analgesia and longer duration of motor block than levobupvicaine alone.