Determining An Optimal Dose Range Of Rocuronium For General Anaesthesia Induction In Thyroid Surgery By Up-and-Down Allocation Sequential Method

Objective: To determine an optimal dose range of rocuronium for a single injection during anaesthesia induction in thyroid surgery with intraoperative neuromonitoring(IONM)by the up-and-down method.Methods: The sample was divided into two groups in the study.GroupⅠ was designed to find the maximum optimal dose of rocuronium bromide that would not affect the IONM results,and groupⅡ was designed to find the minimum optimal dose that would not affect the operation of anaesthesia and surgery.Rocuronium was administered as primary therapy for neuromuscular block in anaesthesia induction.Patients in the two groups were implemented respectively by Dixon sequential method with an initial dose of rocuronium bromide 0.6mg/kg.The dose was then adjusted in 0.05mg/kg gradients each time for the following patient according to the reaction of the previous patient.Recruitment continued until 8 crossovers had occurred in each group.The maximum optimal dose,minimum optimal dose,and their 95% Confidence Interval(95% CI)of rocuronium bromide were calculated by probit regression.Results: The maximum optimal dose of rocuronium was 0.75mg/kg(95% CI0.72-0.79mg/kg)in groupⅠ,and the minimum optimal dose of rocuronium was0.37mg/kg(95% CI-0.19-0.47mg/kg)in groupⅡ.Conclusion: In thyroid surgery,a single injection of rocuronium bromide in the optimal dose range(0.37mg/kg to 0.75mg/kg)can meet the needs of both the utilization of IONM and general anaesthesia during surgical procedures.