Inclusion Criteria:  - Female with American Society of Anesthesiologists (ASA) physical status I-II; Elective thyroidectomy with endotracheal intubation.  Exclusion Criteria:  - History of thyroid surgery A history of preoperative sore throat; Pregnancy; Retrosternal goiter; Thyroid tumor invading trachea need trachea reconstruction; Potentially difficult airway; Clinical diagnosis of chronic sore throat; Clinical diagnosis of psychosis; Tracheotomy after operation； Transfer to intensive care unit after operation； Contraindications to tramadol； Body mass index (BMI) > 30kg/m^2.