Optimal dose of intravenous dexmedetomidine to prevent shivering in cesarean section under spinal anesthesia: A randomized controlled trial

Abstract

Shivering is a common complication during anesthesia that causes patient discomfort, interferes with vital signs monitoring, and increases the risk of perioperative myocardial ischemia. This randomized controlled trial aimed to determine the optimal intravenous dexmedetomidine dose for preventing shivering in patients undergoing cesarean section under spinal anesthesia and to evaluate its adverse effects. A total of 140 parturient aged 18-45 years with American Society of Anesthesiologists physical status I-II scheduled for elective cesarean section under spinal anesthesia between June and August 2025 were randomly allocated into three groups: N group (n = 30) received dexmedetomidine 0.75 µg/kg, L group (n = 55) received dexmedetomidine 10 µg, and C group (n = 55) received normal saline at the same infusion rate. The incidence of shivering, vital signs, sedation scores, and adverse effects were observed intraoperatively and in the recovery room. Shivering occurred in 1 patient (3.3%) in the N group, which was significantly lower than in 12 patients (21.8%) in the L group (p = 0.024). However, both treatment groups were significantly effective in reducing shivering compared with the control group, in which shivering occurred in 23 patients (41.8%) (p < 0.001 and p = 0.024, respectively). Bradycardia occurred significantly more often in the N group. Hypotension occurred in all groups. A dose of 0.75 µg/kg is recommended for the prevention of intraoperative shivering in this setting, as it is significantly more effective than lower doses (p = 0.024).