Effect of esmolol on hemodynamics and intraocular pressure response to succinylcholine and intubation following low-dose alfentanil premedication.

STUDY OBJECTIVE: To determine the effectiveness of esmolol hydrochloride (Brevibloc) as an additional adjunct to low-dose alfentanil premedication in controlling the hemodynamic response [heart rate (HR), mean arterial pressure (MAP), and intraocular pressure (IOP)] to succinylcholine and endotracheal intubation.

DESIGN: Randomized, double-blind, placebo-controlled, prospective study.

SETTING: Ambulatory gynecologic surgery at a university medical center.

PATIENTS: Twenty ASA physical status I and II female patients scheduled for outpatient laparoscopy under general anesthesia.

INTERVENTIONS: All patients received alfentanil 10 micrograms/kg as a preoperative medication 4 minutes prior to induction of anesthesia. Study patients (n = 10 in each group) received either esmolol 1.5 mg/kg or a placebo (normal saline) 30 seconds prior to induction (210 seconds after alfentanil and 90 seconds prior to endotracheal intubation). Anesthesia was induced with thiopental sodium 5 mg/kg and succinylcholine 1 mg/kg. Postintubation, 70% nitrous oxide, 30% oxygen, and 1% isoflurane were administered.

MEASUREMENTS AND MAIN RESULTS: Time of study drug administration was defined as time zero. Measurements of HR, MAP, and IOP were made at baseline (patient awake) and at each minute from minutes 1 through 6 after administration of the study drug (time zero). Analysis of variance was used to analyze the data, with a value of p less than 0.05 considered significant. Esmolol 1.5 mg/kg was found to blunt the maximum increase in HR but not MAP or IOP following low-dose alfentanil premedication.

CONCLUSIONS: In an eye patient with coronary artery disease, or in any patient in whom tachycardia may be detrimental, esmolol may be a useful adjunct in combination with low-dose alfentanil to attenuate the increase in HR due to laryngoscopy and endotracheal intubation.