High-dose dexmedetomidine increases the opioid-free interval and decreases opioid requirement after tonsillectomy in children.

PURPOSE

Dexmedetomidine, a selective α(2) adrenoreceptor agonist, has analgesic and sedative properties, minimal impact on respiratory parameters, and reportedly decreases analgesic requirements after surgery. Given its pharmacodynamic profile, dexmedetomidine might have a role for postoperative pain control in children undergoing tonsillectomy. In this study, we hypothesized that dexmedetomidine would delay and decrease opioid requirements after tonsillectomy.

METHODS

In a double-blind controlled trial, participants undergoing tonsillectomy were randomized to receive one intravenous dose of fentanyl (1 μg·kg(-1) or 2 μg·kg(-1)) or dexmedetomidine (2 μg·kg(-1) or 4 μg·kg(-1)) immediately after endotracheal intubation. Primary outcomes included requirement for rescue morphine in the initial postoperative period.

RESULTS

One hundred and one children were enrolled. During the postoperative period, dexmedetomidine (2 and 4 μg·kg(-1) groups combined) significantly prolonged the opioid-free interval of children who underwent tonsillectomy compared with fentanyl (1 and 2 μg·kg(-1) groups combined) (P < 0.001). Children treated with dexmedetomidine 2 μg·kg(-1) vs dexmedetomidine 4 μg·kg(-1) had similar cumulative incidence curves for time to morphine rescue, whereas there was a small difference in time to first morphine rescue administration when comparing fentanyl 1 μg·kg(-1) vs fentanyl 2 μg·kg(-1). Furthermore, length of stay in the postanesthesia care unit was significantly longer for children treated with dexmedetomidine vs children treated with fentanyl (P = 0.0016).

CONCLUSIONS

High-dose dexmedetomidine decreases opioid requirements, prolongs the opioid-free interval after tonsillectomy, and prolongs length of stay in the postanesthesia care unit. It is conceivable that these early opioid-sparing effects could benefit patients at risk for respiratory complications early in the postoperative course after tonsillectomy (e.g., patients with obstructive sleep apnea). (ClinicalTrials.gov number, NCT00654511).