Comparative Study of Midazolam on the Characteristics of Intrathecal Bupivacaine - A Prospective Randomized Study

Introduction: Spinal Anaesthesia is the most commonly used technique for lower abdominal & lower limb surgeries as it is very economical and easy to administer. A common problem during lower abdominal & lower limb surgeries under spinal anaesthesia is visceral pain, nausea and vomiting. Local anaesthetic agents for spinal anaesthesia are used have various side effects and less duration of action. In order to minimize the side effects and maximize the duration of analgesia, various adjuvants have been used along with local anaesthetics. A number of adjuvants like fentanyl, clonidine, dexmeditomide etc., have been used to improve the quality of subarachnoid block. Midazolam a water soluble benzodiazepine is used to increase the duration of analgesia and facilitate early ambulation and reducing hospital stay of the patient. The aim of the study was to compare the subarachnoid block characteristics with Midazolam to intrathecal Bupivacaine. Methodology: After Institutional ethics committee approved and written informed consent, 100 patients between 16-60 years belonging to ASA I&II were included in the study. Patients were randomly allocated into 2 groups of 50 each. Group-1 received 3ml of 0.5% hyperbaric bupivacaine with 0.5ml of 0.9% Saline. Group-2 received 3ml of Hyperbaric Bupivacaine with 0.5m l (2.5mg) of preservative free midazolam. Total volume made upto 3.5ml to achieve subarachnoid block. Sensory block characteristics, motor block characteristics, Haemodynamic characteristics, adverse effects, duration of analgesia, statistical analysis and results were noted in all groups. Statistical analysis was done with one way analysis of variants. Duration of sensory blockade was significantly longer in group-II than in group-I. (P value < 0.001). Duration of Motor blockade was also higher in group-II only to some extent (P value < 0.01). The first request of analgesia was significantly longer in group-II than group-I. Conclusion: Addition of Midazolam to intrathecal bupivacaine produces better quality of analgesia and without