From the Guidelines
Cardiac Extracorporeal Membrane Oxygenation (ECMO) is a life-saving advanced cardiac support technique that temporarily takes over heart and lung function in patients with severe cardiac failure. This mechanical circulatory support system works by removing blood from the patient's body, passing it through an artificial lung (oxygenator) where carbon dioxide is removed and oxygen is added, and then returning the oxygenated blood back to the patient. In cardiac ECMO, specifically venoarterial (VA) ECMO, blood is typically drained from a large vein (usually the femoral vein) and returned to an artery (commonly the femoral artery), effectively bypassing both the heart and lungs. ECMO is primarily used in critical situations such as cardiogenic shock, cardiac arrest, bridge to heart transplantation, or after cardiac surgery when the heart cannot maintain adequate circulation, as noted in the ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 1. The duration of ECMO support varies from days to weeks, depending on the patient's condition and recovery. Management requires specialized teams including cardiac surgeons, intensivists, perfusionists, and nurses, along with continuous monitoring of anticoagulation (typically with heparin), blood gases, and hemodynamics, as outlined in the position paper for the organization of extracorporeal membrane oxygenation programs for acute respiratory failure in adult patients 1. Some key considerations for ECMO management include:
- Anticoagulation protocols to prevent thrombosis and bleeding complications, with a typical loading dose of 100 U/kg heparin before ECMO cannulation and a continuous infusion of heparin to maintain the ACT between 180 and 220 seconds 1
- Monitoring for potential complications such as bleeding, thrombosis, infection, limb ischemia, and vascular injuries
- The use of heparin-bonded ECMO circuits to limit contact activation and reduce the risk of thrombotic complications
- The potential role of antifibrinolytic agents such as aprotinin, EACA, and TXA to control bleeding and decrease transfusions in congenital heart surgery patients supported on ECMO. ECMO serves as a bridge therapy, providing temporary support until the heart recovers or more definitive treatment options become available.
From the Research
Cardiac Extracorporeal Membrane Oxygenation (ECMO)
Cardiac Extracorporeal Membrane Oxygenation (ECMO) is a life-support therapy used to support the heart and lungs when they are unable to function properly. The key aspects of cardiac ECMO include:
- Providing temporary support to allow the heart and lungs to recover from injury or illness
- Supporting the circulation in case of end-stage cardiomyopathy or as a bridge to transplantation
- Used in emergency or urgent situations after failure of other treatment modalities
Indications for Cardiac ECMO
The indications for cardiac ECMO include:
- Cardiogenic shock after cardiac surgery
- Severe cardiac failure due to cardiomyopathy, myocarditis, or acute coronary syndrome
- High-risk cardiac catheterization procedures
- Post-cardiotomy cardiogenic shock
- Decompensated cardiomyopathy or myocarditis
Types of Cardiac ECMO
There are two main types of cardiac ECMO:
- Veno-arterial (VA) ECMO: used for cardiogenic shock and provides both cardiac and respiratory support
- Veno-venous (VV) ECMO: used for respiratory failure and provides only respiratory support
Outcomes and Complications
The outcomes and complications of cardiac ECMO include:
- Survival rates ranging from 38% to 54.5% depending on the patient population and underlying condition 2, 3
- Complications such as bleeding, renal failure, and multiple organ failure 4
- Successful weaning off ECMO and hospital discharge in a significant proportion of patients 2, 4
Clinical Experience and Evidence
Clinical experience and evidence support the use of cardiac ECMO in various patient populations, including children and adults with severe cardiac or respiratory failure 2, 3, 4, 5, 6. The technical aspects of ECMO cannulation, maintenance, and weaning are critical to successful outcomes 5.