Effect of the pump injection of dexmetomidine combined with remifentanil and propofol on intraoperative nerve monitoring during thyroidectomy

ObjectiveTo investigate the clinical application effects of the pump injection of dexmetomidine(DEX) combined with remifentanil and propofol in intraoperative nerve monitoring(IONM) during thyroidectomy.

MethodsSeventy thyroidectomy patients with IONM were randomly divided into the observation group and control group(35 cases in each group).The observation group was induced by intravenous pumping 0.6 g/kg DEX for the first 10 min, followed by continuous pumping 0.4 μg·kg^-1·h^-1 DEX, and the drug stopped before 30 min of the end of the surgery.The control group was injected with the same amount of 0.9% sodium chloride solution.Two groups were rapidly induced using the 0.05 mg/kg midazolam, 2 mg/kg propofol, 0.4 μg/kg remifentanil and 0.3 mg/kg rocuronium bromide, and a special nerve catheter was inserted into the patient.Remifentanil and propofol were pumped intraoperatively to maintain anesthesia without muscle relaxants.The heart rate(HR), mean arterial pressure(MAP) and bispectral(BIS) index in two groups were recorded before injection(T₀), before anesthesia induction(T₁), and at the time of intubation(T₂), cutting skin(T₃) and isloating thyroid gland(T₄) and extubation(T₅).The dosage of propofol and remifentanil, recovery of anesthesia, postoperative comfort and intraoperative awareness were recorded in two groups.

ResultsThe HR and MAP in observation group at T₁ to T₄ were lower than those at T₀(P < 0.05 to P < 0.01), and the BIS in observation group at T₁ to T₅ were significantly lower than that at T₀(P < 0.01).The HR in control group at T₃ and T₄ were lower than that at T₀(P < 0.05), and the BIS in control group at T₂ to T₅ were significantly lower than that at T₀(P < 0.01).The HR and MAP in observation group at T₁ to T₄ were significantly lower than those in control group at each time-point(P < 0.05 to P < 0.01), and the BIS in observation group at T₁ was significantly lower than that in control group(P < 0.01).Neither group had intraoperative knowledge.The dosage of propofol and remifentanil in observation group were significantly lower than those in control group(P < 0.01).The incidence rate of restlessness in observation group(5.71%)(2/35) was lower than that in control group(25.71%)(9/35)(P < 0.05).The BCS score in observation group after operation was significantly higher than that in control group(P < 0.01).The differences of the opening eye time and extubation time were not statistically significant between two groups(P>0.05).

ConclusionsThe application of DEX combined with remifentanil and propofol in thyroidectomy does not affect the IONM, can meet with operation, reduce restlessness during recovery and improve postoperative comfort.