A Randomized, Double-Blind Clinical Trial Comparing Prophylactic Intravenous Paracetamol and Intravenous Meperidine for Shivering During Cesarean Delivery Under Spinal Anesthesia

Abstract

Background: Shivering is a distressing and common complication of spinal anesthesia for cesarean delivery (CD), with reported incidence rates of up to 55%. It increases maternal metabolic demand, thereby posing risks for patients with cardiopulmonary conditions. Although meperidine is an effective and well-established prophylactic agent, its use is limited by opioid-related adverse effects. Intravenous (IV) paracetamol is a non-opioid alternative that may reduce shivering by centrally modulating the thermoregulatory set point. Objectives: This randomized, double-blind clinical trial compared the prophylactic efficacy of intravenous paracetamol and intravenous meperidine in preventing shivering during CD under spinal anesthesia. Methods: In this randomized, double-blind clinical trial, 151 patients undergoing CD under spinal anesthesia were allocated to receive 1 g IV paracetamol (PARA), 0.3 mg/kg IV meperidine (MEP-IV), or normal saline (CTL) preoperatively. The primary outcomes were the incidence and intensity of shivering, assessed using a 4-point scale. Secondary outcomes included shivering onset time, hemodynamic stability (including mean arterial pressure [MAP] and heart rate [HR]), and adverse events. Longitudinal hemodynamic data were analyzed using repeated-measures analysis of variance. Results: The overall incidence of shivering did not differ significantly among the groups (P = 0.146), with rates of 49.0% in the PARA group, 33.3% in the MEP-IV group, and 49.0% in the CTL group. Although IV paracetamol did not significantly reduce the overall incidence of shivering compared with meperidine or placebo, it was associated with a delayed onset and lower shivering severity. Conclusions: Intravenous paracetamol may represent a potential non-opioid option for managing shivering during CD under spinal anesthesia.