A Comparative Study on Efficacy of Intravenous Dexmedetomidine Vs Intravenous Clonidine to Prolong Bupivacaine Spinal Anaesthesia

Many techniques and drug regimens, with partial or greater success, have been tried from time to time to eliminate the anxiety component and to prolong the postoperative analgesia during regional anesthesia. α 2 agonists like clonidine, dexmedetomidine are used as adjuvant to local anaesthetics in order to prolong the duration of spinal anaesthesia. They potentiate the effect of local anesthetics and prolong the duration of both motor, sensory spinal blockade and postoperative analgesia. The objective of the study was to compare the duration of sensory and motor block, sedation scores, intra-operative haemodynamic stability of the patients, intraoperative and post operative analgesia and side effects between the groups. In this study time of onset of sensory block (2.58±1.18min) and motor block (3.54+0.45* min), time for attaining highest level of sensory block (11.6±1.9 min) were significantly reduced in dexmedetomidine group compared to clonidine and control groups however there is slight reduction in Duration for motor blockade to reach Modified Bromage scale 3. The Duration for 2 dermatomal Regression of sensory blockade (137.4±10.9 mins), duration of sensory blockade (269.8±20.7min) and duration for motor block regression to Modified Bromage scale 0 (220.7±16.5 mins) prolonged significantly than clonidine and control groups. The heart rate, systolic, diastolic and mean arterial pressures were stable indicating the hemodynamic stability. This concludes that intravenous dexmedetomidine and clonidine prolong the spinal anaesthesia and dexmedetomidine was an effective adjuvant than clonidine for bupivacaine spinal anesthesia.