ECMO: An intensive care for patients with severe cardiac and respiratory failure from COVID-19
As a highly contagious and potent disease, COVID-19 can cause a wide range of symptoms and disease severity, extending from mild to fatal, affecting different organs in the body. Very often, serious respiratory complications can develop. Some are even life-threatening that urgently require an intensive care and respiratory assistance. In severe cases with lung damage or multiple organ failure, mechanical ventilators might not be able to sufficiently support the respiratory system. ECMO (Extracorporeal Membrane Oxygenation) can be used to provide prolonged support to cardiovascular and respiratory systems. In ECMO, blood is pumped outside of the body to a membrane that removes carbon dioxide and sends oxygen-filled blood back to tissues in the body. This method allows the blood to bypass the heart and lungs, allowing these organs to rest and heal. ECMO, as a life support, can help lighting up hopes of surviving among patients with critical conditions.
COVID-19 is more deadly than it seems to be
When SARS-CoV-2 enters into the body, it comes into contact with the mucous membranes that line the respiratory system in both upper and lower tracts. The virus enters a healthy cell and multiplies rapidly, allowing the new viruses to infect nearby cells. If it reaches the lungs, the lining can become irritated and inflamed. This inflammation activates the immune system to fight back through several immune mechanisms. Nevertheless, this immune response against the virus can also cause progressive scarring in the lung tissue, leading to lung damages that quickly worsen the symptoms. In addition, severe inflammation elevates blood pressure, causing high blood pressure in the lungs and the swelling or inflammation of lung tissue.
Besides cell destruction affecting respiratory system, SARS-CoV-2 can also systematically reach blood circulation and affect the lining of heart vessels while directly attaching to receptors in the heart. After cardiac vessels and muscles become damaged, patients often exhibit symptoms similar to those who have acute myocardial infarction or heart attack. Without immediate and intensive treatments, patients are at greater risk of death.
In regards to a medical study published on Journal of American Medical Association (JAMA) in April 2020, it indicates that up to 60% of the world populations will be infected with COVID-19. Among this amount, 15-20% of them need to be treated in hospitals whereas 5-10% of these people might require intensive care. Moreover, 50% of patients who urge for intensive care treatments potentially need ventilation support and the mortality rates rise up to 80%.
The role of ECMO
If heart muscles are progressively damaged and pneumonia develops causing lung tissue damages and oxygen insufficiency, oxygen supplement might be required in order to maintain adequate oxygen levels in the blood to supply vital organs in the body. In case that cardiac and respiratory conditions become fatal, mechanical ventilators might not be able manage these conditions. ECMO (Extracorporeal Membrane Oxygenation) can be used to provide prolonged support to cardiovascular and respiratory systems. In ECMO, blood is pumped outside of the body to a membrane that removes carbon dioxide and sends oxygen-filled blood back to tissues in the body. This method allows the blood to bypass the heart and lungs, enabling these organs to fully rest and heal. ECMO, as a life support, can help lighting up hopes of surviving among patients with critical conditions. Nevertheless, ECMO is considered only if patient’s conditions allow and duration of treatment will be thoroughly considered by the specialists.
There are 2 modes of ECMO, including:
- VV-ECMO: VV or veno-venous ECMO primarily supports lung function by removing un-oxygenated blood from the vein through the cannula. The blood is then oxygenated while carbon dioxide is removed. Oxygenated blood will be returned to circulation system through a vein.
- VA-ECMO: VA or veno-arterial ECMO provides both respiratory and cardiac support. The ECMO machine will remove un-oxygenated blood from the vein through the cannula, add oxygen to the blood, remove carbon dioxide and return the blood to the heart through an artery. To support the heart and lungs, VA-ECMO works similar to a heart-lung machine used during open heart surgery.
Referring to updates on ECMO treatment globally revealed by The Extracorporeal Life Support Organization (ELSO) as of 25 May 2020, ECMO machines had been used in approximately 975 COVID-19 patients worldwide with 51% survival rates. The consideration for using ECMO is primarily determined by patient’s age, conditions and disease severity. Nonetheless, ECMO might not be able to save lives if multiple organs are extensively damaged.
Advantages of ECMO in COVID-19 patients
Principle benefits of ECMO among severely ill patients are to save their lives and increase survival rates. Although ECMO might work effectively in several cases, ECMO can become inefficient if patient’s conditions critically progress present with multiple organ failure. In such a case, ECMO might no longer provide any life-saving effect.
ECMO treatment at Bangkok Heart Hospital is conducted by well-certified and experienced specialists. Not only COVID-19 patients, our ECMO with medical evacuation services are ready around-the-clock for patients with critical conditions, e.g. cardiac and respiratory failure in which life saving does matter.