Vasopressor and Inotrope Therapy in Cardiac Critical Care

Abstract

Patients admitted to the cardiac intensive care unit (CICU) are often in shock and require hemodynamic support. Identifying and addressing the pathophysiology mechanisms operating in an individual patient is crucial to achieving a successful outcome, while initiating circulatory support therapy to restore adequate tissue perfusion. Vasopressors and inotropes are the cornerstone of supportive medical therapy for shock, in addition to fluid resuscitation when indicated. Timely initiation of optimal vasopressor and inotrope therapy is essential for patients with shock, with the ultimate goals of restoring effective tissue perfusion in order to normalize cellular metabolism. Use of vasoactive agents for hemodynamic support of patients with shock should take both arterial pressure and tissue perfusion into account when choosing therapeutic interventions. For most patients with shock, including cardiogenic or septic shock, norepinephrine (NE) is an appropriate choice as a first-line vasopressor titrated to achieve an adequate arterial pressure due to a lower risk of adverse events than other catecholamine vasopressors. If tissue and organ perfusion remain inadequate, an inotrope such as dobutamine may be added to increase cardiac output to a sufficient level that meets tissue demand. Low doses of epinephrine or dopamine may be used for inotropic support, but high doses of these drugs carry an excessive risk of adverse events when used for vasopressor support and should be avoided. When NE alone is inadequate to achieve an adequate arterial pressure, addition of a noncatecholamine vasopressor such as vasopressin or angiotensin-II is reasonable, in addition to rescue therapies that may improve vasopressor responsiveness. In this review, we discuss the pharmacology and evidence-based use of vasopressor and inotrope drugs in critically ill patients, with a focus on the CICU population.