View source for Extracorporeal membrane oxygenation

==Overview==
[[File:Veno-arterial (VA) ECMO for cardiac or respiratory failure.jpg|thumb|Veno-arterial (VA) ECMO for cardiac or respiratory failure.]]
[[File:Veno-venous (VV) ECMO for isolated respiratory failure.jpg|thumb|Veno-venous (VV) ECMO for respiratory failure.]]
*Abbreviation: ECMO
**Extracorporeal life support (ECLS) becoming a more common term
*Extracorporeal circuit that oxygenates blood and removes carbon dioxide (functions as an out-of-body lung)
**Can be high flow or low flow
*Similar (but not identical) to cardiopulmonary bypass machine
**Requires lower levels of anticoagulation and allows longer duration of treatment (time on pump)
*Emerging therapy in Emergency Medicine (eCPR) but not yet well studied in this context

===Types===
*Veno-venous (VV)
**Most common
**Blood drained from central vein → oxygenator → vein near RA
**Supports severe respiratory failure without cardiac dysfunction
*Veno-arterial (VA): can be peripheral or central
**Blood drained from central vein → oxygenator → aorta
**Supports cardiac failure with or without respiratory failure
*Veno-pulmonary artery
**Blood drained from central vein → oxygenator → pulmonary artery
**Short term right ventricular/respiratory support after LVAD placement
*Hybrid (VVA or VAV)

==Indications==
*Acute, severe respiratory or cardiac failure + REVERSIBLE cause + refractory to usual treatment + high risk of death
**Poor gas exchange
**Compliance < 0.5ml/cmH20/kg
**P:F Ratio <100
**Shunt fraction >30%
*Veno-venous (VV)
**[[Pneumonia]], [[ARDS]], acute [[GVHD]], [[pulmonary contusion]], smoke inhalation, status asthmaticus, airway obstruction, drowning, bridge to lung transplant
*Veno-arterial (VA)
**Massive PE, nonischemic cardiogenic shock, failure of transplanted heart or heart-lung, cardiac or great vessel trauma, massive pulmonary hemorrhage/trauma, sepsis, anaphylaxis, drug overdose, bridge to LVAD

==Contraindications==
*Absolute
**unwitnessed cardiac arrest
**non-reversible, progressive cardiac disease in a patient who is not a transplant candidate
**non-reversible, progressive respiratory disease
**severe, chronic pulmonary hypertension
**advanced cancer
*Relative
**older than 75 years
**multisystem trauma
**CNS injury
**multiple organ failure
*VV
**unsupported cardiac failure, cardiac arrest, severe pulmonary hypertension, significant immunosupression
*VA
**Aortic dissection or severe aortic regurgitation

==Equipment Needed==


==Procedure==


==Complications==
*Clot formation
*Bleeding
*Suck down and kicking (vessel collapse around access cannula)
*Circut rupture, deccannulation, oxygenator failure, pump failure
*VA can → left ventricle overdistension → cardiac damage, pulmonary bleed or infarction, aortic thrombosis, cardiac or cerebral hypoxia
*North-South syndrome (cephalad hypoxia/cyanosis) may occur in patients with femoral-femoral cannulation for VA support

==See Also==


==External Links==
*[http://www.elso.org Extracorporeal Life Support Organization (ELSO)]
*[http://www.edecmo.org ED ECMO Podcast]

==References==
<references/>

[[Category:Procedures]]
[[Category:Critical Care]]