Abstract
We observed the changes in plasma sodium, potassium, arterial PaCO2, pH and cardiac rhythm after repeated twice administrations of succinylcholine (SCC) for 22 patients of Aichi Cancer Center Hospital during induction of the operations. Anesthesia was induced with thiopental (100-150mg) and modified NLA (droperidol 0.25mg/kg and pentazocine 1mg/kg) . The first dose of SCC (lmg/kg) was administered immediately after the loss of consciousness, and the second dose of SCC (0.5mg/kg) was administered 2 minutes after intubation. Plasma sodium concentration decreased constantly with time. The decrease was 2.3mEq/l in 7 minutes. After induction, plasma potassium concentration decreased by 0.07 mEq/l compared with preinduction levels. However, after the first and the second SCC doses, plasma potassium levels increased by 0.08 and 0.28mEq/l, respectively, compared with prerelaxant concentration. There was no correlation between the changes of plasma electrolytes and blood gas data. Heart rate was significantly reduced after the second SCC dose. Temporary atrial and ventricular premature beats were observed in 2 of 22 patients after the first SCC dose and 3 of 15 patients after the second SCC dose. However, there was no correlation between the occurrence of bradycardia or arrythmia and the change in plasma potassium concentration. These results suggest that in modified NLA we used, the degree of the changes in plasma electrolytes and the occurrence of bradycardia or arrythmia after repeated twice SCC administrations were relatively small compared with other methods of general anesthesia.
