Quick Tip for Families in Intensive Care: When Should ECMO (Extracorporeal Membrane Oxygenation) Be Initiated in Intensive Care?

When should ECMO be initiated in intensive care? That’s what I’m going to answer today.

My name is Patrik Hutzel from intensivecarehotline.com, and this is another quick tip for families in intensive care.

Extracorporeal membrane oxygenation is a lifesaving support system used in ICU for patients with severe cardiac or respiratory failure when conventional treatments are failing. It’s essentially used as a last resort to give the heart and/or lungs time to rest and recover. When to initiate ECMO in intensive care?

Refractory respiratory failure. Veno-venous ECMO, also known as VV ECMO, is used for severe lung failure. Initiation is considered when ARDS, also known as acute respiratory distress syndrome, also known as lung failure, is severe and unresponsive to optimal ventilator support, including high PEEP (Positive End-Expiratory Pressure), prone positioning, neuromuscular blockade, etc. PaO2/FiO2 ratio, less than 80 millimeter per mercury for greater 6 hours, despite optimization.

What that means is if PO2 in an arterial blood gas is less than 80 millimeter per mercury, but FiO2 (Fraction of Inspired Oxygen), which is the oxygen that’s delivered from the ventilator, is going up and up for more than 6 hours, that’s another indication to initiate ECMO. And just to keep in mind, the air that you and I are breathing is room air, it’s 21% of oxygen, whereas if someone needs ECMO, it’s usually at 100% of oxygen from the ventilator. Also, in an arterial blood gas, PaO2 or oxygen levels in the arteries, if it’s less than 80, 70 millimeter per mercury, that’s really when it’s getting concerning and dangerous.

Next, severe hypercapnia with pH less than 7.2, despite maximal ventilator settings. What’s hypercapnia? Hypercapnia is high CO2 or high carbon dioxide. And with high carbon dioxide levels comes a lower ph. And if pH just keeps dropping below 7.2, again, that is when it’s really getting, getting dangerous and it’s a sign of severe, or can be a sign of severe lung failure, and then ECMO needs to be initiated to bypass the mechanisms of the lungs, so that oxygenation and removal of carbon dioxide can happen outside of the body, which is the ECMO machine, so that the body can continue to function. Murray scores greater than 3 or oxygenation index greater than 40.

What’s the Murray scores? It’s a tool used to assess the severity of acute lung injury or acute respiratory distress syndrome in patients. It’s a scoring system designed to evaluate the severity of lung injury in patients with acute lung injury, and ARDS. It considers four key parameters, hypoxemia measured by the PaO2/FiO2 ratio that I just explained.

Positive end expiratory pressure (PEEP), the amount of pressure maintained in the lungs at the end of exhalation, lung compliance, the ease with which the lungs can be inflated, and radiographic findings, assessment of the chest X-ray for signs of lung injury such as infiltrates. And each of these criteria is given a score from 0 to 4, with higher scores indicating more severe impairment. The individual scores are summed, and the total is divided by the number of components to get the final Murray score. A score of 0 indicates no lung injury. Scores between 1 and 2.