Neuromuscular blocking potency of fazadinium in man.

The study was designed to compare the recovery rates of fazadinium and four other commonly used competitive muscle relaxants in forty patients and eight volunteers. One-fifth to 1/10 of the clinical doses of the muscle relaxants were diluted in 20 ml of saline and injected intravenously at the wrist after inflation of a pneumatic tourniquet on the upper arm. After 3 min the tourniquet was released and the recovery time of twitch tension from 25 to 75% of the control determined. Evoked force of middle finger adduction was measured at a frequency of 0.2 Hz. The mean 25-75% recovery times of twitch tension for tubocurarine, pancuronium, alcuronium, gallamine and fazadinium were 14.20 +/- 1.42, 12.30 +/- 1.02, 10.12 +/- 0.77, 10.07 +/- 1.12 and 9.90 +/- 0.87 min, respectively. The authors conclude that the dissociation rate of fazadinum from the receptor of the motor endplate appears to be the fastest among the competitive muscle relaxants studied in man.