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Abstract Extracorporeal membrane oxygenation (ECMO) is a form of partial pulmonary and/or cardiopulmonary bypass used for short term (days to weeks) support of patients in severe pulmonary and/or cardiac failure. ECMO is a form of mechanical assist therapy that employs an extracorporeal blood circuit including an oxygenator and a pump. There are two main types of ECMO: veno-arterial (VA) and veno- venous (VV). VA ECMO provides both cardiac and respiratory support, whereas VV ECMO only provides respiratory support. In adults, VA ECMO is used primarily for refractory cardiogenic shock. In contrast, VV ECMO is favored in patients with isolated severe respiratory failure in the absence of major cardiac dysfunction. More efficient membrane oxygenators and novel cannulation strategies have broadened the indications for which ECMO may offer a benefit, including hypercapnic respiratory failure, cardiogenic shock and cardiac arrest. Ultimately, more studies are needed to determine the appropriate use and clinical impact of ECMO on respiratory and cardiac failure. Once ECMO support has been started, the goal is to preserve all organs and recover those injured. A daily metabolic panel verifies proper perfusion and oxygenation. Arterial gases and coagulation panel readings must be obtained hourly; especially during the first hours of support. ECMO flows should be adjusted according to the patient needs. On one hand, flows should be sufficient to keep 165 a good systemic perfusion measured by urine output, lactic acid levels and mixed venous saturation. On the other hand, ECMO flows should not be high enough to prevent lung circulation. Transesophageal echocardiography (TEE) is the primary form of imaging required during insertion and commencement of ECMO, monitoring patient response, and detecting complications. Systemic anticoagulation is initiated to prevent circuit clotting. Unfractionated heparin is the current international standard for anticoagulation during ECMO. The anticoagulant effect is monitored using activated clotting time (ACT) or partial thromboplastin time (PTT). Most contraindications are relative, balancing the risks of the procedure vs. the potential benefits.The absolute contraindications to ECMO are irreversible lung disease with no indication for lung transplantation and severe brain damage associated with major cerebral infarction or severe intracranial bleeding. The most frequently observed medical complications are hemorrhage and infection. Bleeding is the most common complication and can occur at cannulation sites and can also be life threatening with intracranial hemorrhage. Coagulase-negative Staphylococci and Candida species are common causes of ECMO-related blood stream infection |