Thiopental-nitrous oxide- halothane anesthesia and repeated succinylcholine: comparison of preoperative glycopyrrolate and atropine administration.

: The effects of glycopyrrolate and atropine given prior to thiopental-N2O-halothane anesthesia on bradyarrhythmias associated with the administration of succinylcholine were studied and compared. Sixty healthy adult patients were allocated at random to one of three groups. Three minutes before induction of anesthesia with thiopental (4 to 5 mg/kg) one group received glycopyrrolate, 0.0045 mg/kg IV, the second group, glycopyrrolate, 0.008 mg/kg IV, and the third group, atropine, 0.009 mg/kg IV. Succinylcholine, 1 mg/kg of body weight, was given 1 minute and 6 minutes after the conclusion of the thiopental injection. ECG monitoring was continuous, and serum K+ levels as well as PaO2 and paCO2 were repeatedly measured. In all three groups patients were adequately and equally protected against serious bradyarrhythmias following the second dose of succinylcholine by atropine and glycopyrrolate in the doses used.