What is ECMO? How Does the ECMO Machine Work?

What is ECMO? How Does the ECMO Machine Work?
December 02 13:08 2020 by admin Print This Article

In the normal process of blood circulation, the heart pumps oxygen depleted blood into the lungs which replenish the blood with oxygen. The oxygen-rich blood is sent back to the heart which then pumps it to the rest of the body where it is required. The efficiency of pumping is regulated through blood pressure. The entire process must happen smoothly to ensure a person’s proper health.

However, in some people, this process deteriorates with time or fails completely due to one or more ailments. The lungs cannot provide enough oxygen to the body even when given extra oxygen or they cannot get rid of carbon dioxide even with help of a mechanical ventilator. Sometimes, the heart cannot pump enough blood to the rest of the body.

In such situations, the blood must be artificially oxygenated and then circulated through the body with the required blood pressure. This is precisely what an extra-corporeal membrane oxygenator or an ECMO machine achieves. The ECMO machine ensures critical life-support for the patient even as the doctors treat the underlying condition which required an ECMO in the first place. The ECMO is generally used in the ICU though it can also be used outside.

Ailments That Require ECMO

An ECMO machine is used for both infants and adults. Infants with the following conditions will require ECMO:

  • Congenital diaphragmatic hernia (CDH) and
  • Birth defects of the heart

They will be on ECMO until their lungs and heart are capable of working independently. Further, adults with any of the following conditions will require an ECMO machine for varied lengths of time:

  • Extremely high blood pressure in the arteries of the lungs (PPHN)
  • Severe pneumonia
  • Meconium aspiration syndrome (MAS)
  • Severe air leak problems

How Does the ECMO Machine Work?

The ECMO machine consists of the following parts:

  • A mechanical pump to pump blood at the required pressure
  • A membrane oxygenator where the gas exchange happens
  • A heat exchanger that maintains the blood at the right temperature
  • An access cannula which is a tube through which the blood is drawn out of the body
  • An infusion cannula which is a tube through which the blood is infused back into the body

The cannulas are connected to a prominent artery or vein in the arms or legs through a process called cannulation. The ECMO machine is manned either by a ‘perfusionist’ or by a respiratory therapist (called an ECMO specialist) who has received special training for the same. Either of these specialists continuously monitor the settings on the machine to ensure that the person is receiving the right kind of heart and lung support.

The Patient Experience

 The patient is first given sedatives so that he/she can drift off to sleep. The person is connected to a ventilator or breathing machine through an endotracheal or ET tube which is connected to the nose and mouth and into the windpipe. The cannulas are then connected. Once the person is fully on the ECMO, his/her heart rate, oxygen levels and blood pressure levels are continuously monitored through devices connected to his/her body. Further, the blood is extracted and tested from time to time to check if the oxygen and carbon-di-oxide levels are safe. The patient is given blood thinners to ensure that the blood does not clot, so the blood thickness is also checked frequently. Based on the test results, the settings on the ECMO are adjusted accordingly.

 How Long Is the ECMO Required?

 The ECMO provides critical life-support to patients so that doctors have adequate time to treat the underlying condition. It comes with certain risks such as bleeding, stroke, kidney failure, infection and leg damage. However, doctors are aware of this and will provide the required medication to prevent or overcome these risks. Overall, the benefits of an ECMO machine outnumber the risks. As and when the underlying condition improves, the doctors will take a decision on when to remove the ECMO. In case the patient requires life-long ECMO support, the decision will be taken by the doctors in consultation with the patient and family members.


ECMO is one of the most useful innovations in the world of healthcare. It provides hope to the lakhs of patients fighting life-threatening conditions or awaiting a heart or lung transplant. The machine provides critical life-support to such people and sustains their quality of life, even as they await a new and healthy phase of life.

Kauvery Hospital is globally known for its multidisciplinary services at all its Centers of Excellence, and for its comprehensive, Avant-Grade technology, especially in diagnostics and remedial care in heart diseases, transplantation, vascular and neurosciences medicine. Located in the heart of Trichy (Tennur, Royal Road and Alexandria Road (Cantonment), Chennai, Hosur and Salem, the hospital also renders adult and pediatric trauma care.

Chennai – 044 4000 6000 • Trichy – Cantonment – 0431 4077777 • Trichy – Heartcity – 0431 4003500 • Trichy – Tennur – 0431 4022555 • Hosur – 04344 272727 • Salem – 0427 2677777 • Bengaluru – 080 6801 6801

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  1. denex international
    December 12, 08:20 #1 denex international

    nice blog and very easy to understand your blog keep sharing

    Reply to this comment
  2. Ganesh
    February 21, 20:03 #2 Ganesh

    Interesting info! Thank you for uploading such blogs!

    Reply to this comment

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