Cardiovascular and neuromuscular effects of esmolol during induction of anesthesia.

Sixteen subjects scheduled for surgical procedures under general anesthesia participated in an investigation of the effects of esmolol on the transient hypertension and tachycardia that was observed during endotracheal intubation and on the duration of succinylcholine-induced neuromuscular blockade. In eight subjects, infusion of esmolol was begun five minutes before induction of anesthesia and continued for 12 minutes after induction. In the remaining subjects, an equivalent volume of solvent (D5W) was infused for 12 minutes. Infusion of esmolol significantly attenuated the cardioacceleration observed during intubation without any significant effect on the pressor effects of the procedure. Esmolol delayed the recovery from succinylcholine-induced neuromuscular blockade by less than three minutes. The mechanism of this delay remains to be investigated, although such a delay does not have clinical significance. Esmolol-induced attenuation of the tachycardia seen during intubation may offer a protective effect on the myocardium, especially in elderly subjects and patients with coronary artery disease.