Comparative study of hyperbaric 0.5% bupivacaine and hyperbaric 0.5% bupivacaine with low dose dexmedetomidine in spinal anaesthesia

Abstract

Background: Spinal anaesthesia remains one of the basic techniques in the arsenal of modern anaesthesiology despite the waxing and waning of its popularity over last 100 years since its introduction into clinical practice.It avoids biochemical and metabolic changes consequent to the stress of general anesthesia for surgery as well as provides near optimal conditions for surgery. In present study, we tried to study effectiveness of intrathecal 0.5% heavy bupivacaine alone with Dexmedetomidine as an adjuvant to intrathecal 0.5% heavy bupivacaine for lower limb and lower abdominal surgeries.Methods: The present study was conducted in the department of anaesthesiology from December 2011 to September 2013.This study was a prospective, randomised controlled, single blind, study conducted in 100 patients of ASA grade I and II undergoing elective surgeries under spinal anaesthesia. The patients were divided randomly into two groups, containing 50 patients in each group. Dosages of drugs selected are divided as Group B: Patients received 3 ml of 0.5% hyperbaric bupivacaine (15mg) and Group BD: Patients received 3 ml of 0.5% hyperbaric bupivacaine (15mg) plus 10 µg Dexmedetomidine. Spinal block characteristics, Mean arterial pressure, Mean pulse rate, sedation and side effects were studied during intra-operative and postoperative period.Results: It was found from present study that in Dexmedetomidine group time to reach T10 sensory blockade and complete motor blockade was earlier and a higher level of sensory blockade compared to control group achieved. Duration of sensory, motor blockade and duration of analgesia was significantly prolonged in the Dexmedetomidine group compared to the control group. Hemodynamic parameters were preserved both intra-operatively and postoperatively. However there were a small percentage of patients who developed hypotension and bradycardia which were easily managed without any untoward effect. Hence Dexmedetomidine is a better neuraxial adjuvant for providing early onset of sensory and motor blockade, prolonged sensory blockade and post operative analgesia and adequate sedation.Conclusions: Intrathecal low dose Dexmedetomidine in a dose of 10µg along with 0.5% hyperbaric bupivacaine is an addition into anaesthesiologist's armamentarium for spinal anaesthesia in patients undergoing elective lower abdominal and lower limb surgeries.