FDA Warns of Infection With Another Cooler–Heater Device

Megan Brooks

October 01, 2020

The US Food and Drug Administration (FDA) is warning once again about the potential risk for nontuberculosis mycobacteria (NTM) infection during cardiothoracic surgery using cooler–heater devices.

In a letter to healthcare providers, the FDA says it recently became aware of three patients at one facility who developed sternal surgical-site infections caused by Mycobacterium abscessus, a type of NTM, after undergoing cardiothoracic surgery in which the CardioQuip modular cooler–heater device was used.

NTM patient infections, NTM device contamination, and in some cases both issues, have now been reported for all five manufacturers of heater–cooler devices in the United States, the FDA says.

Heater–cooler devices are used during medical and surgical procedures to warm or cool a patient, as appropriate. The devices include water tanks that provide temperature-controlled water to external heat exchangers or warming/cooling blankets through closed circuits.

Although the water in the circuits does not come into direct contact with the patient, the potential exists for contaminated water to enter other parts of the device or transmit bacteria through the air, via the device's exhaust vent, into the environment and to the patient, the FDA explains.

Ongoing Issue

Between January 2010 and August 2015, the FDA received 32 reports of patient infections associated with heater–cooler devices or bacterial heater–cooler device contamination, with 25 reported in 2015, as previously reported by Medscape Medical News.

The FDA is asking healthcare providers to "remain vigilant for the potential risk of NTM infections in patients who have undergone cardiothoracic surgeries using any heater–cooler device."

Although the FDA believes these infections are "rare," healthcare providers should be aware that these NTM infections can and do occur, the agency advises.

Because patients infected with NTM may not show any symptoms or signs of infection for "months to years" after initial exposure, it is possible that some cases have gone unreported, the agency says.


In addition to following standard precautions, the FDA recommends that healthcare facilities and staff using heater–cooler devices consider implementing the following measures to reduce risk to patients:

  • Strictly adhere to the cleaning and disinfection instructions provided in the manufacturer's device labeling. Ensure availability of the most current version of the manufacturers' instructions for use to promote adherence.

  • Do not use tap water to rinse, fill, refill, or top-up water tanks, as this may introduce NTM organisms. Use only sterile water or water that has been passed through a filter with a pore size no larger than 0.22 μm. When making ice for patient cooling during surgical procedures, use only sterile water or water that has been passed through a filter with a pore size no larger than 0.22 μm. Deionized water and sterile water created through reverse osmosis is not recommended because it can promote corrosion of the metal components of the system.

  • Direct the heater–cooler's vent exhaust away from the surgical field to mitigate the risk of aerosolizing heater–cooler tank water into the sterile field and exposing the patient.

  • Establish regular cleaning, disinfection, and maintenance schedules for heater–cooler devices in accordance with the manufacturer's instructions to minimize the risk for bacterial growth and subsequent patient infection.

  • Develop and follow a comprehensive quality-control program for the maintenance, cleaning, and disinfection of heater–cooler devices. This can include written procedures for monitoring adherence to the program and documenting set up, cleaning, and disinfection processes before and after use.

  • Immediately remove from service heater–cooler devices that show discoloration or cloudiness in the fluid lines/circuits, which can indicate bacterial growth. Consult your hospital infection control officials to perform the appropriate follow-up measures and report events of device contamination to the manufacturer.

  • Consider performing environmental, air, and water sampling and monitoring if heater–cooler contamination is suspected. Environmental monitoring requires specialized expertise and equipment to collect and process samples, which may not be feasible in all facilities.

  • Notify and evaluate patients with an infection suspected to be associated with heater–cooler devices or who have been exposed to a contaminated heater–cooler device. Healthcare facilities should follow their internal procedures for notifying and culturing patients if they suspect infection associated with heater–cooler devices.

  • Report any issues with heater–cooler devices to MedWatch, including heater–cooler devices suspected to have led to patient infections and any type of contamination of a heater–cooler device.


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