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Mechanomyoscopy as an objective method for determining the degree of decurarisation is particularly useful in the case of uncooperative patients and those who are incapable of adequate neck flexion mostly for spinal column diseases. The authors use for that purpose a Czechoslovak-made neuromuscular stimulator (LSN 110), with constant 50 Hz frequency of stimulation, 0.3 ms impulse duration, max. 50 mA and, depending on skin impedance, 5-140 V. The stimulator switch is manually controlled. The absence of muscular fatigue (fade) on single as well repeated stimulation lasting only a fraction of a second necessary to elicit muscular response does not rule out residual curarisation despite the fact that less than 70% of the cholinergic receptors are blocked. The only reliable sign of clinically sufficient decurarisation is the ability of the muscles of the hand to maintain contraction on tetanic stimulation of the motor point of the ulnar nerve in the wrist for at least 5 seconds without fatigue, and that even on a repeated exercise. This corresponds to a block of less than 60% of the cholinergic receptors. The patient's ability to raise his or her head and to keep it raised at 4 fingerbreaths for a period of 4 seconds is also a manifestation of clinically sufficient decurarisation. The value of forced expiratory volume is not conclusive evidence of sufficient decurarisation, it only gives a rough idea of its degree. The final decision is up to the an anaesthesiologist, his knowledge and experience based on objective data.