A Randomized Controlled Study To Evaluate The Effects With Or Without Intravenous Dexmedetomidine As A Pre Medication On Sensory Block Induced By Spinal Anesthesia With 0.5 Percent Hyperbaric Bupivacaine In Lower Limb Surgeries SMS Medical College Jaipur

Spinal anesthesia is a type of regional anesthesia which is commonly used technique for lower abdominal , lower limb surgeries. Spinal anesthesia with bupivacaine is the  most preferred technique of anesthesia . Bupivacaine when used in recommended doses, under spinal anesthesia produces complete sensory and motor blockade. Various adjuvants like dexmedetomidine , opioids are added to enhance the effects of the local anesthetics .Dexmedetomidine potentiates the anesthetic effects of all intraoperative anesthetics, regardless of method of administration .Recent studies show  that dexmedetomidine prolongs the sensory  blockade induced by spinal anesthesia . 

For this a total of 66 patients(n=66) undergoing lower limb surgeries will be randomly divided into two groups(Group A and Group B).Group A patients will receive 10 ml 0.9% normal saline as infusion over 10 minutes ,20 minutes prior to subarachnoid block with 15 mg 0.5% hyperbaric bupivacaine and Group B patients will receive 1mcg/kg body weight dexmedetomidine in 10 ml 0.9% normal saline as infusion over 10 minutes, 20 minutes prior to subarachnoid block. 

Patient will be received in operation theatre , intravenous cannula will be secured and hemodynamic variables will be noted .Loading dose of intravenous dexmedetomidine and normal saline as per study group will be given.

Surgery will be started after T10 level sensory blockade is achieved. Quantitative values of time of onset and duration of sensory and motor blockade ,time taken for sensory regression and request of first rescue analgesia will be recorded.