The participants will be applied AMG and EMG on each arm of both arms when they finish routine monitoring before the induction of general anesthesia. After the participants being unconscious, we will find each participant's supramaximal current before injecting the neuromuscular blocking agents. During the operation, when the TOF count reaches 4 again and the height of T1 reaches 50% of baseline, we perform TOF tests using 4 currents (Supramaximal current, 0.7×supramaximal current, 0.5×supramaximal current, 0.3×supramaximal current), three times for respective current to figure out that low current can show the same level of TOF ratio as the supramaximal current. When the operation ends and the T1 reaches 100% of baseline, we perform TOF tests with 4 currents again. In the postanesthesia care unit, we use EMG only and perform TOF tests with 4 currents again. The participants can feel pain by the stimulants during the tests, so if they refuse the tests, we stop the tests and record it.

Give 4 electrical stimulants on the ulnar nerve to see if the 4 responses (T1 ~ T4) of adductor pollicis fade or not. If there's no neuromuscular block, it shows no fade, or it fades. When an operation is over under general anesthesia, we use the ratio of the height of T4 to T1, and the ratio is over 90%, the neuromuscular block is recovered enough to extubation.

The minimal current among the four currents we use which is showing not significantly lower TOF ratio than TOF ratio of supramaximal stimulant.