Comparative Efficacy and Safety of Intravenous Nalbuphine and Tramadol for Treatment of Post-Spinal Anaesthesia Shivering in Patients Undergoing Lower-Limb Surgery

Abstract

Background: Shivering is a common complication of spinal anaesthesia, affecting 40–70% of patients, and may increase oxygen consumption, metabolic stress, and discomfort. Both nalbuphine and tramadol can be used to control shivering. Objective: To compare the efficacy of intravenous nalbuphine (0.05 mg/kg) and tramadol (1 mg/kg) for post-spinal shivering control in patients undergoing lower limb surgeries under spinal anaesthesia. Methods: In this prospective, randomised, open-label study, 56 patients with Wrench grade III–IV shivering were allocated 1:1 to Group N (nalbuphine, n = 28) or Group T (tramadol, n = 28). The primary outcome was the time to cessation of shivering. Continuous variables were compared using Student's t-test, and categorical variables were compared using Fisher's exact test; Wrench grade comparisons were adjusted using Bonferroni correction. Results: Time to cessation was significantly shorter in Group T (3.54 ± 1.46 vs 4.58 ± 1.52 min; p = 0.012). Wrench grades were significantly lower in Group T at 2, 10, and 15 min (adjusted p = 0.007, < 0.001, < 0.001). Control within 5 min was achieved in 92.9% vs 89.3% (p = 1.000). Recurrence (21.4% vs 10.7%) and rescue medication (7.1% vs 3.6%) did not differ significantly. Haemodynamic appeared comparable. Nausea (17.9% vs 3.6%), vomiting (10.7% vs 3.6%) and sedation (14.3% vs 3.6%) were not statistically different; no respiratory depression occurred. Conclusion: Both drugs controlled post-spinal shivering; tramadol acted faster, whereas nalbuphine may have exhibited a more favourable gastrointestinal adverse effect profile. Both preserved haemodynamic stability and may be suitable for clinical use.

Keywords: Post-spinal shivering; nalbuphine; tramadol; spinal anaesthesia; lower limb surgeries; Wrench grade