The effect of maintenance remifentanil infusion with target controlled infusion during laryngeal mask airway removal on hemodynamic parameters and emergence quality is going to be investigated.

In all patients (control group and remifentanil group induction of anesthesia will be achieved with desflurane and remifentanil.Anesthesia will be maintained with remifentanil (1-4 ng/mL) by TCI target controlled infusion, and desflurane . Throughout the surgery hemodynamic parameters are going to be recorded. As soon as the surgery has been finished, in control group remifentanil infusion and desflurane inhalation is going to be stopped.In remifentanil group,desflurane inhalation is going to be stopped and remifentanil infusion will be maintained until the removal of LMA. During the emergence period the time of eye opening, hemodynamic parameters and emergence quality (score 1-2)are going to be recorded.

Inclusion Criteria:

• ASA I-II status
• aged 18-60 years old
• presenting for ureterorenoscopy

Exclusion Criteria:

• history of hypertension
• asthma and chronic obstructive lung disease
• recent respiratory tract infections

During the surgery

serious and/or other [non-serious] adverse events were not collected/assessed.

The limitation of our study is age and ASA status of the included patients'. The relatively older or ASA status III,IV population may interfere the effect-site concentration TCI of remifentanil