Outline the role of ECMO (Extracorporeal membrane oxygenation) as a supportive strategy in the critically ill.
Indications:
ECMO is indicated as a supportive strategy for patients (adults, children and neonates) with potentially reversible acute severe heart or lung failure with a high mortality risk despite conventional therapy.
Types: Veno-venous or veno-arterial
Evidence for use of ECMO
• ECMO has proven benefit as a supportive strategy in neonates with cardiorespiratory failure. The International Registry reports 75% survival to discharge for neonates on ECMO.
• Recent studies have shown a benefit for the use of ECMO in adult respiratory failure but the evidence for its use in cardiac failure is still poor. CESAR Trial from the UK compared ECMO and conventional ventilation for severe acute respiratory failure in
160 patients with improved 6 month survival in the ECMO group (63% versus 47%). The Australasian experience of the 2009 influenza A (HINI) pandemic (ANZ ECMO Influenza Investigators) reported 68 patients who received ECMO with 21% mortality. All these patients met inclusion criteria for the CESAR trial.
• ECMO also used as a rescue strategy for cardiac arrest (ECPR).
• Several centres world-wide have experience in retrieval and transport of patients with
ECMO.
Complications
• Circuit related
• Anticoagulation/Bleeding
• Sepsis
• Death
Summary statement
• ECMO remains a specialised strategy
• requiring appropriate resources and personnel.
• However its use should be limited to centres with appropriate expertise, resources and experience and facilities for transport and retrieval should be supported.
The question has a broad scope.
Rather than offer a summary of the applications of ECMO (which is done elsewhere) I will instead offer a summary of the literature regarding the use of ECMO
ECMO in neonates:
This has been going on since before 1986. Bartlett et al reported that after the experience, 63% of his patients were "normal or near normal".
ECMO in adults
The CESAR trial from the UK is quoted in the college answer. 63% survival at 6 months was indeed a wonderful thing.Not so for cardiac failure. In one 2004 study, only 37 out of 219 patients survived to 5 year follow-up. This does not seem to have improved with time. In general, nobody over the age of 75 survived to discharge.
ECMO as CPR has initially failed to yield satisfying results. In one study from 2003, the survival rate for patients in whom VA ECMO was started during CPR was 31%. Multi-organ system failure was the culprit there. However, a more recent observational study has produced some encouraging data.These days, it is beginnging to look more and more promising. The obvious disadvantage is that you need an ED which has a circuit cycling 24/7.
UpToDate has a nice summary chapter about ECMO.
The world is sustained by the guidelines published by ELSO (the Extracorporeal Life Support Organisation)
BARTLETT, ROBERT H., et al. "Extracorporeal membrane oxygenation (ECMO) in neonatal respiratory failure." Annals of surgery 204.3 (1986): 236-245.
Peek, Giles J., et al. "Efficacy and economic assessment of conventional ventilatory support versus extracorporeal membrane oxygenation for severe adult respiratory failure (CESAR): a multicentre randomised controlled trial." Lancet (London, England) 374.9698 (2009): 1351-1363.
Doll, Nicolas, et al. "Five-year results of 219 consecutive patients treated with extracorporeal membrane oxygenation for refractory postoperative cardiogenic shock." The Annals of thoracic surgery 77.1 (2004): 151-157.
De Waha, S., et al. "Extracorporeal membrane oxygenation in refractory cardiogenic shock-the Leipzig ECMO registry." European Heart Journal 34.suppl 1 (2013): P4025.
Chen, Yih-Sharng, et al. "Analysis and results of prolonged resuscitation in cardiac arrest patients rescued by extracorporeal membrane oxygenation." Journal of the American College of Cardiology 41.2 (2003): 197-203.
Shin, Tae Gun, et al. "Extracorporeal cardiopulmonary resuscitation in patients with inhospital cardiac arrest: A comparison with conventional cardiopulmonary resuscitation*." Critical care medicine 39.1 (2011): 1-7.
Scanziani, Margherita, Leonello Avalli, and Roberto Fumagalli. "Extracorporeal Membrane Oxygenation Strategy in Cardiac Arrest." Resuscitation. Springer Milan, 2014. 109-117.