Inotropes.

Inotropes are a group of drugs that alter myocardial contractility by increasing intracellular calcium or enhancing sensitivity to it. However, they may result in suboptimal myocardial oxygen supply demand ratios with impaired diastolic filling and greater arrhythmia risk. As shock is frequently encountered perioperatively and in the intensive care unit (ICU), an understanding of its pathophysiology and the pharmacology of inotropes and vasopressors is essential for their rational use. Until resolution of the primary issue, this heterogeneous group of drugs may be used in combination. However, knowing their mechanisms of action is necessary to minimize complications. With advances in our understanding of heart failure pathophysiology novel agents aim to enhance benefit with minimal harm. However, to date, none is in widespread use. Measurement of cardiac output is recommended to guide inotrope administration. This is frequently achieved with devices using pulse contour analysis or ultrasound. As mechanical support devices are more widely available current trends favour their earlier use. [ABSTRACT FROM AUTHOR]