Comparison of the Analgesic Effects of Intravenous Infusion of Dexmedetomidine Versus Bilateral Superficial Cervical Plexus Block After Thyroidectomy: A Randomized Controlled Trial.

Objectives: Dexmedetomidine (DEX) is widely used in clinical practice because of its safety and effectiveness. Superficial cervical plexus block (SCPB) can reduce pain in thyroid surgery. The objective of this study was to investigated whether intravenous DEX has an equivalent analgesic effect and patients' satisfaction to SCPB for thyroid surgery.

Materials And Methods: Ninety patients who had been scheduled for thyroidectomy under general anesthesia with endotracheal intubation were randomly divided into 3 groups. Group D: DEX was administered intravenously at an initial dose of 1 µg/kg over 10 minutes; then induction and endotracheal intubation performed, and then a continuous intravenous infusion of DEX was administered at a rate of 0.4 μg/kg/h until 30 minutes before the end of surgery. Group B: ultrasound-guided bilateral SCPB was performed, with 10 mL of 0.375% ropivacaine injected on each side. Group C: intravenous saline was administered at the same rate and dose as in group D. Patients' perioperative status, visual analog scale scores, complications and patients' satisfaction were recorded.

Results: The pain at rest at 1 hour after extubation and the movement-evoked pain within 24 hours after extubation were significantly lower in groups D and B than in group C. Patients' satisfaction was significantly higher in groups D and B than in group C. There was no difference in pain at rest, movement-evoked pain and patients' satisfaction between group D and B.

Conclusions: Perioperative intravenous infusion of DEX can effectively reduce wound pain after thyroidectomy, and the analgesic effect is equivalent to that of bilateral SCPB.