Inotropes, vasopressors and vasodilators

Description

Inotropic and vasopressor agents have increasingly become a therapeutic cornerstone for the management of several important cardiovascular syndromes. Vasopressors induce peripheral vasoconstriction, increasing systemic vascular resistance (SVR) and mean arterial pressure (MAP). Inotropes increase the force of cardiac contractility, increasing cardiac output and MAP. Chronotropes increase heart rate. Some agents produce only one of these actions, whereas others have multiple effects. In broad terms, these substances have excitatory and inhibitory actions on the heart and vascular smooth muscle, as well as other systems. They are generally administered with the assumption that short- to medium-term clinical recovery will be facilitated by enhancement of cardiac output (CO) or vascular tone that has been severely compromised by often life-threatening clinical conditions. A better understanding of the physiology and important adverse effects of these medications should lead to directed clinical use, with realistic therapeutic goals. Although disease-specific guidelines provide a framework for vasopressor, inotrope, and chronotrope selection and usage, real-world applications demand therapy be tailored to the individual patient. This presentation  reviews the physiologic receptors targeted by such drugs, common agents used, and specific clinical indications for their use.