Abstract: A muscle relaxation monitoring apparatus includes a calibration processing section. The calibration processing section is configured to: set an initial stimulation current value as a starting stimulation current value; determine, as a current value variable process, one of a first and a second current value variable process; detect, as a first peak value and a second peak value, amplitude peak values of an electric signal; and detect a stimulation current value of a maximal stimulation of a subject, based on a result of a comparison of the first peak value and the second peak value, and acquires a stimulation current value that is obtained by adding a step current value to the stimulation current value, as the stimulation current value of a supramaximal stimulation of the subject.

Abstract: A muscle relaxation monitoring apparatus includes: a stimulating circuit that stimulates a nerve of a living body; a signal detecting circuit that detects an electric signal generated by a muscle reacting to the stimulation performed by the stimulating circuit; a reaction time calculating circuit that calculates a reaction time which elapses from the stimulation of the nerve by the stimulating circuit until the electric signal is detected by the signal detecting circuit; and a relaxation degree determining circuit that determines a muscle relaxation degree of the living body based on the length of the reaction time calculated by the reaction time calculating circuit.