The FDA issued a notice today saying that it is working to evaluate new strategies to mitigate infections associated with heater-cooler devices.
According to the notice, the administration is collaborating with professional societies, public health partners, heater-cooler manufacturers, and experts on the matter surrounding the heater-cooler devices used during medical and surgical procedures to warm or cool a patient. Although fluid in the circuits does not directly contact the patient, there is the potential for contaminated fluid to enter other parts of the device or transmit bacteria through the air through the device’s exhaust vent or other unsealed openings, reaching the environment and the patient.
Previous issues have arisen around these devices, including with LivaNova’s 3T Heater-Cooler device. In 2016, the FDA warned patients and doctors about the risk of a type of bacterial infection associated with the device. Later that year, the U.S. Centers for Disease Control & Prevention warned of the risk of serious bacterial infection in open-heart surgery patients using the 3T Heater-Cooler.
LivaNova is one of three companies manufacturing and distributing these devices in the U.S. FDA’s report deems its cleaning, disinfection and aerosolization as “adequate,” while results are still pending for the other two companies: CardioQuip and Gentherm Medical.
As part of its push to encourage innovation in this space, the FDA cleared Spectrum Medical’s Quantum heater-cooler and the compatible Qura Quantum PureFlow heat exchangers in May 2022. Instead of using water, the device regulates the temperature of a glycol-based heat transfer fluid (HTF), which then enters the PureFlow heat exchangers to regulate the temperature of a patient’s circulating blood, mitigating the risk of contamination of the device by suppressing the growth of bacterias, which has been identified as the root of the issue with such devices.
The FDA’s analysis of the issue has determined that potential root causes of the issue include nontuberculous mycobacteria (NTM) bacteria being transmitted through the air through the aerosolization process. Another potential cause is laminar flow disruption (an engineering control designed to protect an operating room environment by reducing airborne contaminants during surgery) associated with the device’s exhaust fan.
Additionally, as the designs of most heater-cooler devices are similar, some contain air filters and water filters while others do not. Air filters on some units aren’t sufficient enough to capture NTM bacteria, while fans on most units may facilitate the movement of aerosolized NTM from inside the unit into the operating room and potentially into the sterile surgical field.
“Based on the agency’s many years of experience reviewing reprocessed devices and research conducted by the agency and others, the FDA has identified designs that foster innovation in next-generation reusable medical devices,” the administration said. “These design features facilitate cleaning and disinfection and reduce the likelihood of contamination and aerosolization.
“The FDA continues to engage with manufacturers, health care facilities, and public health experts in evaluating new design features for heater-cooler devices.”
