In all patients, standard monitors, and state and response entropy (SE and RE, respectively) will be applied. Neuromuscular blockade is measured with a train-of-four (TOF) (Datex-Ohmeda Division, Instrumentarium Corporation, Helsinki, Finland). The forearm is immobilized to prevent interfering movements. The ulnar nerve will be stimulated supramaximally at the wrist with a TOF stimuli (60 mA for 200 μsec) at 15-sec intervals. Baseline twitch amplitude is established after induction of anesthesia. TOF ratio is recorded as ratio between the fourth and the first twitch (T4/T1).