dobutamiini

Dobutamiini, more commonly known as dobutamine, is a synthetic catecholamine used as a cardiovascular inotrope to increase cardiac output in situations of poor heart function. It is administered intravenously and is primarily employed in acute care settings, including decompensated heart failure, cardiogenic shock, and during certain cardiac procedures. It is also used in pharmacologic stress testing of the heart (dobutamine stress echocardiography).

Mechanism of action and pharmacology: Dobutamine acts mainly as a beta-1 adrenergic receptor agonist, enhancing myocardial contractility (positive inotropy) and stroke volume. It has some beta-2 activity and relatively little alpha-1 activity, which can produce mild vasodilation and a small decrease in afterload. The net effect is an increase in cardiac output with often only modest changes in heart rate. It is rapidly acting when given IV, with a short half-life of around a few minutes, and is metabolized by catecholamine pathways (COMT and MAO). Dosing is individualized and adjusted to achieve hemodynamic goals.

Administration and dosing: Dobutamine is given as a continuous IV infusion, typically starting at 2.5–5 micrograms per kilogram per minute and titrating upward to improve cardiac output, often up to 20 micrograms/kg/min, with a maximum around 40 micrograms/kg/min depending on response and tolerance. Preload status should be optimized, and patients monitored for rhythm, blood pressure, and signs of ischemia.

Safety and monitoring: Common adverse effects include tachycardia, arrhythmias, chest discomfort, and fluctuations in blood pressure. It should be used with caution in tachyarrhythmias, significant outflow tract obstructions, uncorrected hypovolemia, or in patients on certain medications that interact with adrenergic pathways.