The Effect of Intravenous Dexmedetomidine During Surgery in the Prevention of Shivering After General Anesthesia in Patients Undergoing Spinal Surgery: A Randomized Clinical Trial.

Background: Postoperative shivering is an involuntary, spontaneous, and repetitive contraction of skeletal muscles that causes patient restlessness, increased oxygen consumption, wound infection, surgical bleeding, and cardiac events. Patients undergoing spine surgery in the prone position are particularly susceptible to hypothermia.

Objectives: Given the importance of controlling postoperative shivering in these patients, the present study aimed to investigate the effect of intraoperative dexmedetomidine (Dex) infusion in preventing shivering after general anesthesia in patients undergoing spine surgery in the prone position.

Methods: In this double-blind randomized clinical trial, 60 American Society of Anesthesiologists (ASA) class I or II patients undergoing vertebral surgery in the prone position were enrolled. Patients in the study group (n = 30) received Dex infusion during surgery, while those in the placebo group (n = 30) received an equivalent volume of 0.9% normal saline. Hemodynamic variables, frequency and severity of shivering, and drug side effects were recorded.

Results: The mean arterial pressure (MAP) at 90 minutes (P = 0.022), immediately before extubation (P = 0.001), and after extubation (P = 0.001), as well as HR values at 60 minutes (P = 0.020), 90 minutes (P = 0.001), immediately before extubation (P = 0.001), and after extubation (P = 0.001), were significantly lower in the study group compared to the placebo group. The frequency of bradycardia (26.7% vs. 0%, P = 0.002) and hypotension (20% vs. 0%, P = 0.012) was significantly higher in the study group. At all evaluated times, the mean body temperature in the study group was significantly higher than in the placebo group (P < 0.05). The frequency (10% vs. 30%, P = 0.003) and intensity (P = 0.001) of shivering in the study group were significantly lower than in the placebo group.

Conclusions: This study demonstrated that the preventive use of Dex infusion during surgery reduces the frequency and severity of postoperative shivering in patients undergoing spinal surgery in the prone position. However, this method was associated with hypotension and bradycardia in some patients.