Intravenous Ondansetron, Nefopam, and Paracetamol for Prevention of Post-Spinal Shivering During Caesarean Section: A Randomized, Controlled, Double-blind Study

Abstract

Background: Shivering is a common complication of spinal anaesthesia, with an incidence of approximately 50%-60%, and is associated with increased perioperative morbidity. Although several pharmacological agents have been investigated for its antishivering prophylaxis, each has inherent limitations, and the optimal prophylactic agent remains a subject of ongoing debate. This study compared the anti-shivering efficacy of prophylactic intravenous paracetamol, ondansetron, and nefopam in obstetric patients undergoing spinal anaesthesia. Methods: Eligible obstetric patients were randomly allocated into four groups: Group P (paracetamol, n = 16), Group O (ondansetron, n = 16), Group N (nefopam, n = 16), and Group C (normal saline, n = 16). The primary outcome was the incidence of post-spinal shivering. Secondary outcomes included the severity of shivering, incidence of nausea, vomiting, hypotension, and perioperative haemodynamic variables. Continuous variables were analysed using one-way analysis of variance (ANOVA), while categorical variables were analysed using the chi-square test. A p-value of <0.05 was considered statistically significant. Results: No patient in the nefopam group developed shivering. The incidence of shivering was significantly lower in the ondansetron and nefopam groups than in the control group (p < 0.001), with nefopam demonstrating complete prophylaxis. Patients who developed shivering in the ondansetron group predominantly experienced mild-to-moderate shivering, whereas those in the paracetamol and control groups mainly exhibited moderate-to-severe shivering, with the difference being statistically significant. The incidence of nausea, vomiting, hypotension, and the perioperative trends in heart rate, mean arterial pressure, and peripheral oxygen saturation were comparable across all study groups. Conclusion: Prophylactic intravenous nefopam demonstrated the greatest efficacy in preventing post-spinal shivering in obstetric patients undergoing spinal anaesthesia, followed by ondansetron and paracetamol. Nefopam may therefore be considered a superior prophylactic agent for the prevention of post-spinal shivering in this patient population.