Till date, the most common mode of death in death certificates is cardiorespiratory failure. Even, if rest of the system and the body is intact, cardio/respiratory arrest is synonymous with cessation of life. Over the years, it was quite frustrating, to watch helplessly, our patients succumbing untimely, to cardiac and / or respiratory in sufficiency, after all machines and medicines fail to assist the heart and / or the lung to minimum efficiency.
What is ECMO
ECMO is a set of machines used for temporary replacement treatment (not assist) of heart and/or lung function by mechanical means via extracorporeal route. It comprises of set of tubings to divert the venous blood from the body to a artificial heart(blood pump). This heart pump provides the necessary force (blood pressure) for the blood to circulate without and within the body. After this, the blood is diverted inside the tubings to a artificial lung (respiratory filter) for oxygenation and removal of carbon dioxide. Then the blood is returned back to the body with pressure and oxygen to perfuse and ventilate the cells of the body.
What is the need to initiate ECMO (principles of treatment)
Till now, all modalities of critical management were assist therapy whether it may be IABP or ventilator or inotropes. They were to support the existing organ and improve its performance. But if the organs are damaged beyond a particular limit, they require absolute rest for recovery. Also, if rest to the organ is not given at proper time, it will lead to cumulative and collateral damages. Thus at this stage, further step up in assist mechanism will create more harm than good.
Other applications of ECMO
We feel, there is a great future of ECMO due to its wide applications, like first line short term replacement therapy in all refractory acute heart or lung failure, e-CPR, organ preservation in brain dead donors and switch over therapies.
Its advantages and challenges
It is a simple percutaneous procedure which can be initiated in short time. It can be done at bed side in any ICU without the need of any specialised machines. It is portable system and allows patients to be shifted across great distances by any transport and can be combined with other support systems. It has great flexibility and various combinations can be designed to support only heart / only lungs or both heart and lungs.
There is lot of physiology involved about hematology and haemorheology, physics of cannulae and pump, chemistry of respiratory membrane and hemofiltration, biology of the living, dying and dead cells, pathology of the disease process and overall medicine for management of the entire body. Thus, entire science is at work and the operator has to master of all and not jack of one. The challenge is worth taking and success is gratifying to the extent of playing GOD