A Comparative Study of Intrathecal Tramadol–Bupivacaine (Heavy) Versus Fentanyl–Bupivacaine (Heavy) for Spinal Anaesthesia in Lower Abdominal Surgeries: A Prospective Randomised Controlled Trial
Abstract
Objective: To compare the onset and duration of sensory and motor blockade, postoperative analgesic efficacy, haemodynamic profile, and adverse effect incidence between intrathecal tramadol–bupivacaine (H) and fentanyl–bupivacaine (H) in adults undergoing elective lower abdominal surgery. Methods: A prospective, randomised, double-blind controlled trial was conducted at Narayan Medical College and Hospital, Sasaram, Bihar, India (June 2023–May 2025). One hundred ASA Grade I–II patients were randomised equally: Group T received intrathecal 0.5% hyperbaric bupivacaine 15 mg with tramadol 25 mg; Group F received the same bupivacaine dose with fentanyl 25 μg. Primary outcomes were onset and duration of sensory and motor block. Secondary outcomes included time to first rescue analgesia, VAS pain scores, haemodynamic parameters, and adverse effects. All continuous variables were confirmed normally distributed (Shapiro–Wilk p>0.05) before parametric analysis. Results: Both groups were demographically comparable (p>0.05 for all baseline parameters). Onset of sensory block was significantly faster in Group F (3.2±0.7 min vs. 4.3±0.9 min; p<0.001). Duration of sensory block (185.4±12.6 vs. 172.2±10.4 min; p<0.001) and time to first rescue analgesia (212.4±18.6 vs. 195.8±16.4 min; p<0.001) were significantly prolonged in Group T. VAS scores and total number of rescue analgesic doses were significantly lower in Group T at all postoperative time points. Pruritis occurred exclusively in Group F (10.0% vs. 0.0%; p = 0.022). Conclusion: Intrathecal tramadol–bupivacaine (H) provides superior duration of analgesia and a lower incidence of pruritis compared to fentanyl–bupivacaine (H), with equivalent haemodynamic safety. It represents a clinically advantageous and cost-effective choice for spinal anaesthesia in lower abdominal surgery.