Assessment of Effectiveness of Addition of Midazolam to Intrathecal Bupivacaine for Infra-Umbilical Surgeries in School-Age Children: A Randomised Controlled Trial

Abstract

Introduction: To increase the duration of spinal anaesthesia, many intrathecal adjuvants are used such as opioids, ketamine, clonidine and neostigmine. However, there are many drawbacks in their utility such as such as respiratory depression, cardiovascular instability, severe nausea and vomiting. Various studies have been conducted that have confirmed the effectiveness of intrathecal midazolam in post-operative analgesia in adults. But the data on efficacy and safety of intrathecal midazolam in children is limited. Aims/ objective: To assess of effectiveness of addition of midazolam to intrathecal bupivacaine for infra-umbilical surgeries in schoolage children and study the effect of adding intrathecal midazolam on quality and duration of anaesthesia and post-operative analgesia and sedation. Materials and Method: After intrathecal administration of 0.5% hyperbaric bupivacaine, patients of control group were given 0.5 ml of normal saline intrathecally and patients of midazolam group were given 0.5 mg of midazolam via intrathecal route. Time to achieve sensory block, time to achieve motor block, effectiveness of post-operative analgesia using the observational pain–discomfort scale (OPS) and effectiveness of post-operative sedation using the modified Wilson Sedation Score (WSS) was recorded and compared. Results: Time to reach sensory block and time to reach motor block was significantly lower in midazolam group (p<0.05). No significant difference was found between two groups with respect to duration of surgery, post-operative hospitalization, mean arterial blood pressure and heart rate. Significantly better postoperative analgesia and sedation was found in midazolam group with respect to OPS score, modified bromage score and modified WSS score. Conclusion: Addition of Midazolam to intrathecal bupivacaine for infra-umbilical surgeries in school-age children was associated with better intra-operative and post-operative outcomes. Longer duration of spinal anaesthesia with better quality of sensory and motor block was achieved.