Atropine electrocardiogram effects

Atropine s peripheral effects on heart rate (Fig. 63) and blood pressure (not shown) are substantial and very rapid in onset, peaking at about 30-60 minutes. In this graph, baseline heart rate is shown as zero. Maximum heart rate at the ID50 is thus about 125 (60 + 65). It remains at this level for about 3 hours and returns to normal at about 9 hours. At the ID50, minor changes in the electrocardiogram were noted in a study by Hayes et al.. These changes rapidly revert to normal as HR declines. 

Hayes, A H.. Jr., Copeland, H., Ketchua, J.S. 1969 The Effect of High Intramuscular Doses of Atropine Sulfate on the Human Electrocardiogram. Edgewood Arsenal Technical Report 4220. 

Dauchot P, Gravenstein JS. Effects of atropine on the electrocardiogram in different age groups. Clin Pharmacol Ther 1971 12(2) 274-80. 

Initial laboratory data included a blood ethanol of 190 ing/dL, hut electrolytes were normal. An electrocardiogram revealed atrial fibrillation with a high degree of atrioventricular block The ventricular rate did not exceed 50/min. Atropine had no effect on the ventricular rate and a transvenous pacing catheter iros therefore inserted, with ventricular pacing instituted at 60/min. 

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