Effect of Age on the Establishment of Muscle Paralysis Induced in Anaesthetized Adult Subjects by ORG NC 45

Abstract

The establishment of muscle paralysis produced by a single dose of 70 micrograms . kg-1 of ORG NC 45 was studied in 30 healthy anaesthetized patients, aged 15-85 years, by recording adductor pollicis isometric mechanical activity-twitch height (TH). Significant correlations were observed between age and the latency of ORG NC 45 action, defined as the reduction of TH to 95% of its initial value (r:0.315, P less than 0.05) and between age and the onset time, defined as the time elapsing between ORG NC 45 administration and maximum TH depression observed (r:0.454, P less than 0.005). Correlation between age and maximum TH depression was not significant. These results show that if the maximum TH depression observed after a standard dose of ORG NC 45 is not altered by the age of the patient, the establishment of the paralysis is delayed by ageing.