There are two types of ECMO - Venoarterial (VA) ECMO, which provides the heart and lung support, and venovenous (VV) ECMO, which provides only lung support.
VA ECMO supports the function of the patient's heart and lungs by diverting most of a person's blood to the ECMO circuit without the blood flowing through the patient's heart and lungs. VA ECMO draws out blood from a large vein and into the ECMO circuit. The venous blood in the ECMO circuit is oxygenated and returned into a large artery, allowing oxygen-rich blood to circulate through the body. In adults, VA ECMO is commonly used in conditions causing cardiac arrest and cardiogenic shock such as heart attack, myocarditis, cardiomyopathy, pulmonary embolism and primary graft failure after heart transplant. It is also used in conditions like poisoning, endocrine emergencies, sepsis, trauma, and organ donation. Most commonly, patients are on VA ECMO for 5-10 days.
VV ECMO supports the function of patient’s lungs only, hence a persons’ heart must still function well to meet the body's needs. It draws most of the patient’s venous blood out of a large vein and into the ECMO circuit. The venous blood in the ECMO circuit is oxygenated and returned to the right atrium and the patient's own heart pumps the blood throughout the body. It is therefore important the patient’s heart is strong enough to pump the oxygenated blood in the right atrium, through the non-functioning lungs, to the rest of the body. In adults, common indications for VV ECMO is lung failure due to pneumonia and adult respiratory distress syndrome. It is also used in aspiration, drowning, respiratory burns, lung trauma, airway obstruction, and post lung transplantation. Most commonly, patients are on VV ECMO for 10-14 days.
ECMO treatment is a high-risk procedure with significant complications including bleeding, stroke, sepsis and limb ischemia, and should only be used when all other conventional treatments such as mechanical ventilation (breathing machine), inotropes (medications that help with heart's contractions), intraaortic balloon pump (device that helps the heart pump more blood), have failed. In this group of critically ill patients, ECMO can save approximately, 60% with respiratory failure, 40% with cardiogenic shock and 30% with cardiac arrest.
NHCS has been performing ECMO since 2001 and is the largest ECMO centre in Singapore; performing about 75 procedures per year. NHCS has a mobile unit that can be activated to initiate ECMO at peripheral hospitals and bring the patient back to NHCS for management.
Eligibility Criteria for Adult ECMO
