Electrocardiogram at the time of anesthesia induction as well as operation were studied in sixteen surgical patients aged from twelve to seventy-nine. The anesthesia was induced with intravenous thiopenthal (Ravonal) followed by succinylcholine chloride (S. C. C.).
Generally speaking, the changes in electrocardiogram, mainly consisted of ventricular extrasystoles and sinus tachycardia, were observed in most of the cases especially during endotracheal incubation, occasionally with serious ventricular complexes. Awkward techniques and procedures of endocracheal intubation resulted in definite changes in electrocardiogram, while basic heart disease itself seemed to be partially responsible for the changes thereafter.
