Perioperative use of esmolol

Stressful surgical stimuli, such as endotracheal intubation, surgical incision, organ manipulation and emergence from anesthesia, elicit adrenergic responses that precipitate transient but intense increases in heart rate and blood pressure. Although this response is well tolerated in healthy patients, patients with ischemic heart disease are at significant risk of myocardial ischemia and infarction owing to the sudden increase in myocardial oxygen demand. Parenteral beta blockers are effective in blunting this adrenergic response, but the duration of action of these agents is long-lasting and the degree of beta blockade is often difficult to predict. Further, long-acting parenteral beta blockers may cause adverse effects, the reversal of which presents a difficult clinical problem in patients with ischemic heart disease. The availability of esmolol, an ultrashort-acting parenteral beta-adrenergic antagonist with a half-life of 9 minutes, brings obvious advantages to the perioperative management of hypertension and tachycardia. With esmolol treatment, the difficulties of therapy with long-lasting beta blockers are avoided. Also, to blunt the adrenergic response, the anesthesiologist will have an alternative to increasing the depth of anesthesia, which can accentuate cardiovascular depression and prolong awakening and postoperative respiratory depression. Clinical studies performed during the perioperative period reveal that esmolol is safe and effective in this setting. Esmolol has been shown to be safe and efficacious in patients in ASA classifications I through IV and patients undergoing carotid endarterectomy and coronary artery bypass surgery. The pharmacokinetic profile, rapid onset and elimination half-life make this agent particularly well suited to treat the very intense but transient adrenergic responses to surgical stress in patients undergoing cardiac and noncardiac surgery.