Female gender patients undergoing thyroidectomy

Male gender patients undergoing thyroidectomy

Targeted effect-site TCI remifentanil for preventing cough effectively during emergence from general anesthesia. For effect-site TCI of remifentanil, a TCI pump was used and pump operation was based on Minto and colleagues' pharmacokinetic model. By Dixon's up-and-down method, the predetermined effect-site concentration(Ce) of remifentanil was determined according to the cough response of the previous patient. The initial target Ce of remifentanil for the first patient was 2.0 ng/ml. If the patients did not cough throughout the peri-extubation period, the predetermined Ce of remifentanil for the subsequent patient was decreased by 0.4 ng/ml. If the patient coughed anytime around extubation, the predetermined Ce for the subsequent patient was increased by 0.4 ng/ml. The stopping rule, as well as for the requirement of at least six turning points in the same direction of the sequential allocation response graph, required the recruitment of more than 20 patients.

The cough was defined as a sudden contraction of the abdomen. The level of cough was assessed and recorded by the following cough grading system: Grade 0, no cough; Grade 1, single cough with mild severity; Grade 2, cough persistence less than 5 sec with moderate severity; Grade 3, severe, persistent cough for more than 5 sec.

The patients will be followed from Sevolurane off to being transported to PACU.