Esmolol

Esmolol is an ultra-short–acting B₁-selective adrenoceptor antagonist. The structure of esmolol contains an ester linkage; esterases in red blood cells rapidly metabolize esmolol to a metabolite that has a low affinity for receptors. Consequently, esmolol has a short half-life (about 10 minutes). Therefore, during continuous infusions of esmolol, steady-state concentrations are achieved quickly, and the therapeutic actions of the drug are terminated rapidly when its infusion is discontinued. Esmolol may be safer to use than longer-acting antagonists in critically ill patients who require a -adrenoceptor antagonist. Esmolol is useful in controlling supraventricular arrhythmias, arrhythmias associated with thyrotoxicosis, perioperative hypertension, and myocardial ischemia in acutely ill patients

It must be diluted to 10-20mg/ml before use it. Beware of dilute with sodium bicarbonate solutions. In Supra ventricular Taquicardia: response i often acquired with doses of 50-200mcgs/kg/min now that higher doses doesn't yield a better response and augment the adverse reactions risk. Initiate treatment with 500mcg/kg/min for a minute and then continue with a mantenance dose of 50 mcg/kg/min for 4 minutes. In case of enought quantity, repeat the squeme: load 500mcg/kg/min and menteinance dose 150mcgs/kg/min for 4 minutes. When desired effect is acquired continue with 200 mcgs/kg/min.