Why ECMO for ARDS?
In the setting of severe ARDS, oxygen delivery can become insufficient to satisfy the body's demand. The main purpose of respiratory ECMO is to maintain oxygenation of the organs. It can stabilize gas exchange and minimize hemodynamic compromise, thus preventing further organ damage.
ECMO is not a treatment for the underlying cause of ARDS. It allows time for investigation and to develop a specific treatment strategy targeted at the underlying disease.
What is ECMO?
ECMO refers to a circuit that directly oxygenates and removes carbon dioxide from blood through an extracorporeal gas exchange device, commonly referred to as a membrane oxygenator. Two catheters or cannulas are inserted at the initiation of ECMO with their drainage and reinfusion ports located in central vessels. Deoxygenated blood is drained from the body by an external pump, it passes through the membrane oxygenator and is then reinfused back into the patient. Respiratory or venovenous ECMO which provides only gas exchange support.
About extracorporeal membrane oxygenation (ECMO)
The use of extracorporeal membrane oxygenation (ECMO) for the treatment of ARDS was introduced in the early 70‘s with the aim of guaranteeing a protective ventilation and minimizing the risk for the ventilator induced lung injury . It works similar to an artificial lung providing adequate blood CO removal and oxygenation thus minimizing mechanical ventilation.  
Transport on ECMO
Because ECMO is considered an advanced therapy. It requires training in the necessary techniques and the formation of a network of hospitals to manage these patients is essential. In cases of severe ARDS, ECMO transport may be safer than transport on ventilation when transferring to an ECMO management center is necessary. 
Extracorporeal Life Support
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