Sedative and Analgesic Effect of Intravenous Dexmedetomidine in Patients Undergoing Meshplasty for Inguinal Hernia Repair under Spinal Anaesthesia: A Prospective Study.

ABSTRACT

Background: We studied the sedative and analgesic effect of intravenous dexmedetomidine in patients posted for meshplasty for the repair of inguinal hernia under subarachnoid block with 0.5% hyperbaric bupivacaine. Methods: Fifty patients of the American Society of Anaesthesiologists (ASA) physical status I or II of either sex (20 – 50 years) presenting for meshplasty for inguinal hernia were included in the prospective double-blind randomized study. All patients received 2.5 ml of 0.5% hyperbaric bupivacaine intrathecally. Patients were randomly allocated on the basis of a sealed envelope technique to receive one of the following after subarachnoid block Group D (n=25) - Loading dose of 1 μg kg-1 dexmedetomidine over 10 minutes started 20 minutes after spinal block + maintenance dose of 0.4 μg kg-1 hr-1 dexmedetomidine till the end of surgery; Group P (n=25) - same calculated volume of normal saline as a loading dose over 10 minutes + maintenance till end of surgery. Data regarding the VAS score, duration of analgesia were recorded. Results: Patients in group D had a significantly higher sedation score than those in group P (p< 0.001). Dexmedetomidine significantly reduced the requirement of diclofenac injection for pain relief in 24 hours postoperative period (p< 0.001). Conclusion: Intravenous dexmedetomidine resulted in significant prolongation of time to VAS ≥ 4, reduced postoperative analgesic requirement and produced good sedation levels without significant haemodynamic compromise.