Hypotension: In clinical trials 20-50% of patients treated with Esmolol HCl have experienced hypotension, generally defined as systolic pressure less than 90 mmHg and/or diastolic pressure less than 50 mmHg. About 12% of the patients have been symptomatic (mainly diaphoresis or dizziness). Hypotension can occur at any dose but is dose-related so that doses beyond 200 micrograms/kg/min (0.2 milligrams/kg/min) are not recommended. Patients should be closely monitored, especially if pretreatment blood pressure is low. Decrease of dose or termination of infusion reserves hypotension, usually within 30 minutes.
Cardiac Failure: Sympathetic stimulation is necessary in supporting circulatory function in congestive heart failure, and beta blockade carries the potential hazard of further depressing myocardial contractility and precipitating more severe failure.
Continued depression of the myocardium with beta blocking over a period of time can, in some cases, lead to cardiac failure. At the first sign or symptom of impending cardiac failure, Esmolol HCl should be withdrawn Although withdrawal may be sufficient because of the short elimination half-life of Esmolol HCl, specific treatment may also be considered (see Overdosage). The use of Esmolol HCl for control of ventricular response in patients with supraventricular arrhythmias should be undertaken with caution when the patient is compromised hemodynamically or is taking other drugs that decrease any or all of the following: Peripheral resistance, myocardial filling, myocardial contractility, or electrical impulse propagation in the myocardium. Despite the rapid onset and offset of the effects of Esmolol HCl, severeal cases of death have been reported in complex clinical states where Esmolol HCl was presumably being used to control ventricular rate.
Intraoperative and Postoperative Tachycardia and/or Hypertension: Esmolol HCl should not be used as the treatment for hypertension in patients in whom the increased blood pressure is primarily due to the casoconstriction associated with hypothermia.
Bronchospastic Disease: Patients with bronchospastic diseases should, in general not receive beta blockers. Because of its relative beta1 selectivity is not absolute. Esmolol HCl should be carefully titrated to obtain the lowest possible effective dose. In the event of bronchospasm, the infusion should be terminated immediately; a beta2 stimulating agent may be administered if conditions warrant but should be used with particular caution as patients have already have rapid ventricular rates.
Diabetes Mellitus and Hypoglycemia: Esmolol HCl should be used with caution in diabetic patients requiring a beta blocking agent. Beta blockers may mask tachycardia occurring with hypoglycemia, but other manifestations such as dizziness and sweating may not be significantly affected.