Extracorporeal membrane oxygenation
Due to the expense and intensity of critical care, guidelines about how to implement life-sustaining and life-saving technologies warrant careful attention. Although consensus around when ECMO is indicated is still developing, the use of ECMO has grown in recent years and continues to rise subsequent to the H1N1 pandemic in 2009. Because the availability of ECMO is limited and requires specialized medical care, liberalizing its use in the intensive care or operating room settings has important policy implications.
Primary criteria ranking
- Safety = High
- Efficacy = High
- Cost = High
- Draft key questions published: September 24, 2015
- Public comment period: September 24 - October 8, 2015
- Final key questions published: October 20, 2015
- Draft report published: December 16, 2015
- Public comment period: December 16, 2015 - January 14, 2016
- Final report published: February 12, 2016
- HTCC public meeting: March 18, 2016
Extracorporeal membrane oxygenation (ECMO) is a form of life support that provides cardiopulmonary assistance outside the body. ECMO may be used to support lung function for severe respiratory failure or heart function for severe cardiac failure. An ECMO circuit can be set up as veno-venous (VV) or veno-arterial (VA). VV-ECMO provides external gas exchange, bypassing the lungs and protecting them from high tidal volumes of ventilation that would otherwise be needed to oxygenate and ventilate the patient. VV-ECMO is indicated for patients with potentially reversible respiratory failure, including those with severe acute respiratory distress syndrome (ARDS), primary graft dysfunction following lung transplant, and trauma to the lungs.
VA-ECMO provides the same external gas exchange as VV-ECMO, but also augments blood flow in settings of severe cardiac injury. VA-ECMO is indicated for patients with cardiac failure, including cardiogenic shock unresponsive to typical intensive care medicines and cardiac arrest that does not respond to cardiopulmonary resuscitation (CPR). VA-ECMO may also be used for patients following heart surgery or as a bridge to heart transplantation. Finally, both VA- and VV-ECMO may be used intraoperatively as a planned alternative to traditional cardiopulmonary bypass in selected patient populations (e.g., lung or heart transplantation). Other external gas exchange systems provide similar functions without the pump component of VV- or VA-ECMO. These arteriovenous extracorporeal lung assist (pECLA) devices bypass the lung, but not the heart, and use the patient’s blood pressure in order to sustain circulation of the externally oxygenated blood. Because of the requirement for adequate cardiac function, these systems have more limited application.
ECMO is a well-established treatment for infants with lung and heart failure and has become a standard of care in many pediatric care centers. In contrast, the evidence base for its use among adults is still emerging. Early studies of ECMO in adults found ECMO to be associated with poor survival rates. However several developments have prompted renewed interest and wider utilization of ECMO in recent years. First, technological advancements have improved the safety of the technique and broadened the application to include ambulating patients. Technological improvements include heparin-coated cannulae, new oxygenators, and pumps. Second, more recent clinical trials have shown improved survival without severe disability with ECMO compared to conventional ventilator support. Finally, the 2009 H1N1 pandemic spurred increased demand for ECMO at rates higher than previously seen, resulting in additional evidence of a survival benefit.