Post-tetanic count(PTC) was a known monitoring method to evaluate intense neuromuscular blockade of peripheral muscles. It has been reported that intermittent tetanic stimulation(50 Hz for 5 sec). Every 6 to 10 min. during intense nondepolarizing
neuromuscular blockade did not influence the recovery of neuromuscular transmission. However, the relatively frequent use of tetanic stimulation might be possible to influence the recovery of neuromuscular blockade and the repeated stimuli might
result
in a false recovery state. The purpose of this study was to determine the best interval time of tetanic stimulation for evaluation of the correct PTC. Sixty adult patients undergoing stomach operations were randomly allocated to three groups
according
to the interval of tetanic stimulation; group 1 (6 min. n=20), group 2 (8 min. n=10) and group 3 (10 min. n=20). In all cases, Anesthesia was maintained with 50% nitrous oxide, 50% oxygen and 1-2% enflurane following induction of anesthesia with
thiopental sodium 3-5 mg/kg Neuromuscular block was achieved by intravenous pancuronium bromide 0.13 mg/kg before application of ulnar nerve stimuli using Myotest MKII(. The adduction force of the resultant thumb twitch was measured by the
acceleration
of a small piezo-electric ceramic wafer with electrodes of Mini-accelograph( and recorded by Datascope 2200 I(. After 1 Hz single twitch stimulation, a tetanic stimulus(50 Hz) was applied for 5 sec. Three seconds later, the single twitch
stimulation was
again applied for 1 min. followed by 1 min. of TOF stimulation. This pattern of tetanic stimulation was continued by the interval of 6, 8 and 10 min. @ES The results were as follows: @EN 1. The continuance (which was the percentage when PTC was
continuously increased, not intermittently reduced) was 73.7% in group 1 and 2. But 100% in group 3 and there were statistically signincance. 2. In the regression analysis between PTC and time from PTC1, we yielded the following.
|