It has been accepted generally that gallamine triethiodide is excreted unchanged in the urine. Furthermore, it has been assumed that the excretion of gallamine is the prime determinant of the duration of this compound and duration of action of gallamine is dose dependent. As a consequence many clinicians consider the use of gallamine in patients with established or potential renal insufficiency, or undergoing bilateral nephrectomy to be contraindicated. Prolonged, sometimes fatal, postoperative neuromuscular block has been reported after the usd of gallamine in such patient.
In order to study the influence of renal funtion on the neuromuscular blocking effect of large single dose of gallamine, the duration of action was measured by single-twitch response using cat´s sciatic nerve-gastrocnemius muscle preparation. Twenty-four cats were used for this study and subdivided into 3 groups: group j ; control group, group U ; unilateral renal pedicle ligation, group 1; bilateral renal pedicle ligation. The animals were anesthetized with intramuscular injection of nembutal, 60 mg/kg. Following tracheostomy and intubation, the lungs were artificially ventialted with room air to deliver 40 ml/kg at a rate of 20 breaths/minute. And a stable pH, 7. 34-7.46 was maintained throughout the experiment. The body temperature was kept at 35-37C by thermoblanket. An infusion rate of Ringer´s lactate solution was 10 drops/minute.
The degree of neuromuscular block and time inteval taken to 25%O (T25) , 50%(T50), 75% (T75) and 90%(T90) recovery of control twitch height were measured after intravenous injection of gallamine 4mg/kg. The sciatic nerve was stimulated supramaximally by a single stimulus with square waves. (0.2msec duration, 0. 1 Hz frequency)
The results were as follows;
1) The mean time to produce 100% block was 140 sec in group j , 128 sec in group R, and 127 sec in group I respectively. No significant time difference was observed between each groups.
2) The mean spontaneous recovery time to return to 90% recovery of control twitch height was 128 min. in group I and 217 min. in group j[ . Significant time difference was observed between group I and group ff.
3) In group 1, spontaneous recovery to 25% twitch height of control twitch height was noted in 2 cases only and no recovery was noted in the other 6 cats.
4) In the absence of bilateral renal funtion, neuromuscular paresis would be occured after the use of large single dose of gallamine. The paresis may last many hours even a few days.
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