After nasal surgery, emergence cough or straining will produce venous engorgement and increase bleeding from the surgical site, so the necessity for smooth extubation without severe cough during emergence provides a challenge for the anesthetists. Recently, remifentanil is commonly used short-acting opioid, and several studies have demonstrated the antitussive effect of remifentanil via effect-site target-controlled infusion during emergence. However, there may be gender difference in response to opioid, and the previous studies about antitussive effect of remifentanil are targeted at female patients and there is no investigation of effect site concentration of remifentanil for male patients undergoing nasal surgery. The purpose of this study is to evaluate the effect-site concentration of remifentanil via target-controlled infusion for preventing cough in man after sevofluorane balanced anesthesia.

Inclusion Criteria:

• all male aged 18-60 years
• ASA(American Society of Anesthesiologists)physical status I or II
• who underwent ESS(endoscopic sinus surgery)or septoplasty under sevoflurane-remifentanil balanced anesthesia

Exclusion Criteria:

• predicted difficult airway,
• BMI(Body Mass Index) of more than 30 kg/m2,
• chronic respiratory disease,
• recent respiratory track infection,
• chronic coughing,
• significant cardiovascular,
• hepatic or renal disease,
• current smokers
• medical history of medication of opioid or ACEI(angiotensin covering enzyme inhibitor)