Comparison of the effects of fentanyl, remifentanil, and dexmedetomidine on neuromuscular blockade

The aim of our study was to compare the effects of fentanyl, remifentanil, and dexmedetomidine on neuromuscular blockade under sevoflurane anesthesia.

Eighty-four patients were randomized to fentanyl, remifentanil, and dexmedetomidine groups. In the fentanyl group, fentanyl 1.5 μg/kg was given before induction of anesthesia, and additional 50-μg boluses were administered. In the remifentanil group, the initial dose of remifentanil 1 μg/kg was infused in 10 min before induction and 0.1 μg/kg/min infusion was continued during anesthesia. In the dexmedetomidine group, the initial dose of dexmedetomidine 1 μg/kg was infused in 10 min before induction and 1 μg/kg/h infusion was continued during anesthesia. Heart rate, blood pressure, SpO₂, EtCO₂, and TOF (train-of-four) values of all patients were monitored during anesthesia. Times to reach TOF 0 and TOF 25% and intubation quality were recorded.

T ₀ times and quality of intubation were found to be similar among the groups. T ₂₅ time was found to be significantly longer in the dexmedetomidine group than in the fentanyl and remifentanil groups.

Dexmedetomidine infusion increased the duration of neuromuscular blockade with vecuronium during general anesthesia. In addition to analgesic and sedative effects, dexmedetomidine may enhance the duration of neuromuscular blockade and may be used as an adjuvant anesthetic during general anesthesia.