64 Acute Circulatory Failure Pharmacologic and Mechanical Support Saul Flores, Barbara A Elias, Lara S Shekerdemian Abstract Acute circulatory failure (ACF) is a clinical syndrome characterized by sudden reduction in blood flow and decreased oxygen delivery to tissues Although there is a wide array of etiologies for ACF in children, the most frequent causes are congenital heart disease and primary myocardial disease, such as myocarditis and cardiomyopathy The clinical signs of ACF are of primary perfusion failure, manifested as compensated or decompensated shock states However, for more subtle and insidious presentation of ACF, a high index of suspicion obtained from a detailed investigation will lead to its early recognition Additional diagnostic tools such as laboratory measurements and echocardiography may facilitate the diagnosis of ACF After identification of patients with ACF, noninvasive and invasive monitoring techniques assist clinicians to further delineate the pathophysiology of ACF The management of children with ACF requires individualized treatment strategies Current approaches favor therapies that optimize systemic blood flow while protecting the myocardium by afterload modification, reduction in oxygen demand, and myocardial rest The three mainstay therapies available to clinicians in the intensive care unit are mechanical ventilation to optimize cardiopulmonary interactions, the use of pharmacologic agents to improve contractility and loading conditions, and extracorporeal life support (ECLS) to augment cardiac output while allowing myocardial rest These treatment strategies are often used in combination and allow clinicians to care for these patients during this challenging stage Furthermore, the development of specialized ECLS teams has expanded its safe use and improved the outcomes in children with ACF A multidisciplinary-team approach and the development and implementation of a large multiinstitutional registry in ECLS has assisted clinicians to identify areas in need of investigation and improvement to better care for these children Keywords Cardiac failure; congenital heart disease; extracorporeal life support