Comparative Evaluation of Bupivacaine Plain Versus Bupivacaine with Fentanyl in Spinal Anaesthesia for Lower Abdominal and Lower Limb Surgeries.

Abstract

Spinal anaesthesia is a safe, effective, and widely used technique for lower abdominal and lower limb surgeries. Bupivacaine, a long-acting amide local anaesthetic, provides satisfactory anaesthesia but limited postoperative analgesia. The addition of opioids such as fentanyl to intrathecal bupivacaine has been shown to enhance sensory blockade and prolong analgesia due to synergistic interaction at the spinal cord level without significantly affecting motor recovery or haemodynamic stability. Objectives:  To compare the clinical efficacy of intrathecal plain bupivacaine and bupivacaine with fentanyl in terms of onset and duration of sensory and motor block, duration of postoperative analgesia, haemodynamic stability, and adverse effects in patients undergoing lower abdominal and lower limb surgeries. Methodology:  Patients were divided into two equal groups. Group A received 2.5 mL of 0.5% hyperbaric bupivacaine with 0.5 mL of normal saline, while Group B received 2.5 mL of 0.5% hyperbaric bupivacaine with 25 μg (0.5 mL) of fentanyl intrathecally. Sensory and motor block characteristics, haemodynamic changes, and duration of analgesia were recorded. Data were analysed using Student’s t-test and Chi-square test, with p < 0.05 considered statistically significant. Results: The onset of sensory and motor block was similar in both groups. The duration of sensory block and postoperative analgesia was significantly longer in the fentanyl group (p < 0.01). No significant difference was found in motor block or haemodynamic parameters. Minor side effects, including pruritus and nausea, were observed only in the fentanyl group, with no respiratory depression reported. Conclusion:  The addition of 25 μg fentanyl to 0.5% hyperbaric bupivacaine prolongs sensory blockade and postoperative analgesia without increasing side effects or compromising haemodynamic stability, making it a superior combination for spinal anaesthesia in lower abdominal and lower limb surgeries.