Low-Dose Intravenous Dexmedetomidine for Postspinal Shivering During Cesarean Delivery: A Randomized Double-Blind Trial Showing Comparable Efficacy With Fewer Adverse Effects at the Lower Dose.

Shivering after spinal anesthesia for cesarean delivery is common and may increase metabolic demand, impair monitoring, and reduce maternal comfort. Dexmedetomidine is effective for control of shivering, but the optimal intravenous treatment dose remains uncertain. This prospective randomized double-blind trial compared dexmedetomidine 0.2 µg/kg and 0.5 µg/kg for treatment of established shivering after cord clamping. Parturients with grade 3 or 4 shivering received one of the two study doses intravenously over 10 minutes. The primary outcome was time to shivering attenuation to grade 1 or less. Secondary outcomes included vasopressor requirement, nausea, hypotension, bradycardia, respiratory depression, sedation, and perioperative temperature change. Fifty-nine participants were included in the analysis. Median time to shivering attenuation was shorter with 0.5 µg/kg than with 0.2 µg/kg, but the difference was not statistically significant. Shivering resolved within approximately 10 minutes in both groups. The 0.5 µg/kg dose was associated with greater vasopressor use and more nausea, whereas no significant bradycardia, respiratory depression, or excessive sedation occurred in either group. Both regimens were effective, however, 0.2 µg/kg offered similar clinical benefit with fewer adverse effects and may represent the more practical treatment dose in obstetric anesthesia.