Nefopam for Analgesia Following Cardiac Surgery: A Randomized Placebo-Controlled Double-Blind Clinical Trial

Abstract

Objective: To evaluate the analgesic efficacy, opioid-sparing effects, and safety profile of nefopam compared with placebo following elective cardiac surgery. Design: Randomized, double-blind, placebo-controlled trial at a tertiary care center. Setting: Perioperative care. Participants: A total of 103 adults (mean age, 57.9 ± 11.3 years) undergoing elective cardiac surgery via median sternotomy were randomized to receive nefopam (n = 50) or placebo (n = 53). Interventions: Patients were randomized to receive nefopam (20 mg intravenous [IV] bolus, followed by an 80 mg continuous infusion over 24 hours) or placebo, with both groups receiving standardized IV fentanyl via patient-controlled analgesia. Measurements and Main Results: The primary outcome was cumulative fentanyl consumption over 48 hours. Secondary outcomes included pain scores (NRS 0-10), intubation duration, intensive care unit (ICU)/hospital length of stay, and adverse events. Both fentanyl consumption and pain scores were assessed at 3, 6, 12, 24, and 48 hours postoperatively. The nefopam group consumed 25% less fentanyl over 48 hours (mean, 16.3 ± 1.6 µg/kg vs 21.9 ± 1.6 µg/kg; p = 0.014), with significant reductions from 6 hours to 48 hours. Pain scores were lower in the nefopam group at rest at 48 hours (p = 0.03) and during movement at 24 and 48 hours (p = 0.04 and 0.01), although overall pain remained mild. Adverse events (eg, sinus tachycardia, agitation/delirium) were comparable in the 2 groups. Duration of intubation and ICU/hospital length of stay did not differ between the 2 groups. Conclusions: Nefopam was well tolerated and associated with statistically significant but clinically modest reductions in fentanyl use and pain scores after cardiac surgery, supporting its role as a safe adjunct in multimodal analgesia.