Of 89 heater-cooler devices tested by researchers between July 2015 and December 2016, 33 tested positive for Mycobacterium chimaera, a bacterium tied to fatal infections in open-heart surgery patients.
The research was presented at the 44th Annual Conference of the Association for Professionals in Infection Control and Epidemiology and published in the American Journal of Infection Control.
M. chimaera is a type of nontuberculous mycobacteria, and previous studies demonstrate a link between heater-cooler devices and NTM infections in open-heart surgery patients.
Researchers took 653 water samples from 89 heater-cooler devices received from 23 hospitals in 14 states, the District of Columbia and Canada. Thirty-three of them tested positive for M. chimaera and four were colonized with Legionella. Researchers also found other NTM species and fungi.
"The extent of contamination from such a rare organism in multiple units from all over the country was surprising," John Rihs, vice president of laboratory services at Special Pathogens Laboratory, said in a statement.
Heater-cooler devices use water tanks, but the water does not come in contact with patients. Instead, the water can aerosolize and transmit bacteria to the patient.
"These results highlight the importance of monitoring the decontamination and maintenance schedules of these devices to minimize the risk of patient harm," said Linda Greene, RN, president of APIC. "Hospitals must follow the cleaning and disinfection instructions provided in the manufacturer's device labeling, as well as updated communications from the FDA and CDC."
The CDC and the Food and Drug Administration have both previously issued guidance on the devices. They recommend hospitals notify patients who have had open-heart surgery in the last five years if they were at risk for infection.