A Comparative Study of Intrathecal Hyperbaric Bupivacaine 0.5% with Morphine and Dexmedetomidine in Lower Limb Orthopedic Surgeries: A Double-Blind Randomized Clinical Trial

Anesth Essays Res. 2022 Jul-Sep;16(3):373-377. doi: 10.4103/aer.aer_116_22. Epub 2022 Nov 15.

Abstract

Background: Pain and its alleviation have been a challenge for humans for centuries. Sub arachnoid block is most commonly practiced method for anaesthesia for lower limb surgeries. Adjuvants like opioids and alpha 2 agonists have proven benefits in augmentation of effects of local anaesthetics for spinal anesthesia. The aim of this study was to compare the effects of morphine and dexmedetomidine for sub arachnoid block in lower limb orthopaedic surgeries.

Material and methods: This is a prospective randomised controlled trial done in 120 patients who were posted for lower limb orthopaedic surgery. Along with bupivacaine, Group A received intrathecal dexmedetomidine while group B received intrathecal morphine.

Results: the demographic profile was comparable in both the groups. The mean duration of motor block in Group A was 359.33 ± 34.4 and in Group B was 265.71 ± 28.47. The duration of rescue analgesia was almost double in Group A as compared to Group B with P < 0.0001 (CL 95%).

Conclusion: Intrathecal dexmedetomidine and morphine both provided good postoperative analgesia. Dexmedetomidine provided a longer duration of analgesia than morphine, thereby increasing the time for first rescue analgesia, but at the cost of greater side effects.

Keywords: Alpha-2 agonist; intrathecal opioid; postoperative pain; spinal anesthesia.