Letter: Pancuronium tachycardia

To the Editor.— In reference to the letter by Orkin and Pegg (224:630, 1973), we want to emphasize that in our study,1specially designed to evaluate the circulatory effects of pancuronium, namely, its influence on electrocardiograms, blood pressure, plasma free-epinephrine and norepinephrine concentrations in combination with blood gases, less than 10% elevations of the heart rate and blood pressures were observed, and no rise in plasma catecholamines. These findings are further corroborated by the lack of increase in heart rate, blood pressure, and in catecholamines when pancuronium, 0.09 mg/kg of body weight, was followed by ketamine hydrochloride, 2.0 mg/kg, and these were administered to good-risk, young, gynecologic patients in our study. Evidently, pancuronium blocked the development of tachycardia, hypertension, and the rise in plasma free-norepinephrine caused otherwise by ketamine, 2.0 mg/kg, intravenously administered in our previous study.2 Therefore, we routinely utilized 0.08 mg/kg pancuronium for facilitation of intubation