Non-tuberculosis mycobacteria are among the germs that just are just sort of everywhere and don’t do much harm to people. The exception, though, is when they gain access to a person’s chest cavity or an artificial heart valve, and can be deadly. The bacteria get there by hitching a ride from a piece of surgical equipment, and patients generally aren’t warned that this is a risk during operations involving the heater-cooler machine.

The devices work alongside a heart-lung machine during surgeries that require its use, ensuring that the patient’s blood is returned to their body at the right temperature.

They’re essential in these operations, but problems with them can also cause deadly outbreaks. While an investigation into an outbreak in Greenville, SC that sickened 15 people and killed four found the bacteria in multiple spots around the hospital, one of those spots was the heater-cooler machine used in chest surgeries.

“Only the heater-cooler device is capable of aerosolizing that bacteria and spraying it directly into the chest cavity during surgery,” an attorney representing one patient’s family in a wrongful death suit against the hospital told our sibling publication, Consumer Reports.

There have been more incidents involving the machines and non-tuberculosis mycobacteria (NTM) in the years since that outbreak in South Carolina. In the last six years, the Food and Drug Administration knows of at least nine deaths and at least 45 infections linked to the machines, mostly to devices from a European company, LivaNova.

The problem is that the FDA doesn’t make public the names of the hospitals where these incidents happened. The devices are essential to what are now common surgeries, and the FDA says that while the absolute risk is small, it’s possible for bacteria to escape the cooling system and be aerosolized around the room… including into the patient’s open chest wound.

Infections are so rare and the bacteria grow so slowly that an infection may not become bad enough to seek medical attention until years after the surgery. Yet at a recent FDA panel on the topic, surgeons debated whether it’s wise to alert patients, potentially frightening them even more before live-saving surgery, over something with a very small absolute risk.

Yet if patients aren’t told what symptoms of NTM would look like and what to look for in the coming years, that puts them at a disadvantage.

“Without that notice, patients don’t know what symptoms to watch out for and can’t be promptly treated with antibiotics, making recovery less likely,” explains Lisa McGiffert, director the Safe Patient Project at Consumer Reports.

The Frightening New Risk in Heart Surgery [Consumer Reports]

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