You may have heard of the word "ECMO" frequently in recent news reports and wonder what it is. ECMO is used globally as a last resort to save COVID-19 patients.

ECMO is short for extracorporeal membrane oxygenation. It is a machine used to replace heart and lung function in open-heart surgery. In simple words, it allows the heart and lungs to rest, by pumping and oxygenating a patient's blood outside the body.

We know that the novel coronavirus mainly attacks the lungs, therefore, although not designed for COVID-19, ECMO has been used as an adjunct support for COVID-19 patients in critical condition, since the beginning of the outbreak.

For COVID-19 patients, their lung function is significantly impaired by the virus, which could cause serious respiratory insufficiency and low level of oxygen in their blood. These are indications of ECMO.

Once connected, the machine can temporarily replace the patient's cardio-pulmonary function for gas exchange and blood circulation to keep other organs working, buying doctors' time to save the patient.

You may think that once connected to ECMO, COVID-19 patients will survive no matter how sick they are. Unfortunately, that's not true.
As a way of life support, ECMO cannot guarantee that the patient will be brought back to life, and has its limitations.

First, ECMO is not suitable for every patient. One premise is that patients can use ECMO only if their lung function can be restored after being removed, and other organs are working relatively well. For seniors with underlying diseases, the risk of death is higher with ECMO.

Second, patients treated with ECMO will experience some lung function impairment. Although the remaining lung function can support daily life, full recovery is impossible.

Also, complications could happen during ECMO treatment. Therefore, we need to be clear that ECMO is just a temporary replacement for cardiopulmonary function. It can indeed save lives, but the key to patients' survival lies in whether the primary disease can be effectively treated, in this case, COVID-19.

So, even if there is a last resort to save coronavirus patients, the best way we can protect ourselves is by taking protective measures to avoid infection in the first place.

(Video filmed by Fu Gaoliang; Cover image designed by Pan Yufei)