Breathe in, breathe out. Many have heard the phrase before; maybe at the doctor’s office while getting their heart and lungs checked, or when being told to calm down in preparation for an anxiety-inducing event. Whatever the case, most don’t have to think twice about following the command. And that’s thanks to having a healthy respiratory system, which allows us to take in oxygen from the air and release carbon dioxide waste from the body.

But what happens when a person’s lungs don’t function anymore? Often, medical professionals would recommend a lung transplant, but for some, even that isn’t possible. Such was the case for a 33-year-old man who was diagnosed with not only severe acute respiratory syndrome (ARDS), but also with necrotizing pneumonia, a form that can be life-threatening. Left with few choices, medical professionals decided to craft an artificial lung system that would oxygenate the patient’s blood, remove carbon dioxide, and maintain blood flow,all without the need for functioning human lungs.

In healthy individuals, deoxygenated blood enters the heart through the right atrium, where it eventually flows to the lungs to receive oxygen and release carbon dioxide waste. The newly oxygenated blood then returns to the left atrium of the heart and through the aorta, where it can travel to various areas of the body, supplying oxygen and nutrients to tissues.

However, for this particular 33-year-old, an influenza-B infection along with an antibiotic-resistant bacteria led to a blood infection, which ultimately was causing severe lung failure. Though other avenues of treatment were pursued, doctors concluded that the patient’s lungs had suffered irreversible damage.

Rather than opting for a traditional lung transplant, in which a healthy pair of human donor lungs replaces the patient’s diseased pair, the medical team decided to connect the patient to an artificial lung system. This way, the system circulated blood outside the body, adding oxygen and removing carbon dioxide while maintaining the blood flow needed for the heart to function properly.

The system, called an extracorporeal total artificial lung (TAL), allowed the patient to clear the infection from his body, making him a more promising candidate for a lung transplant. Soon after use of the extracorporeal TAL system, the man received a lung transplant and now, two years later, he was reported to be healthy and thriving.

This innovation has opened the door to the future of artificial organs. While the extracorporeal TAL was only intended as a temporary fix (with the long-term goal of receiving a lung transplant), future research could explore permanent artificial organs, which would allow for more patients to receive treatment when donors are not available.

Regardless of what the future may bring, the next time you hear “breathe in, breathe out,” consider what such a simple task can mean to someone else, who can no longer rely on their own lungs to do the breathing.