Cardiac Surgery infections through heater cooling systems

Sharon McLeay
Times Contributor

 

Alberta Health Services put out an advisory out on Dec. 1, that 11,500 Alberta pediatric and adult open-heart surgery patients might have been exposed to mycobacterium chimaera infections, introduced through the use of heater-cooler systems in surgery.
The units are used at the Foothills Medical Centre and the Mazinkowski Heart Institute and the Stollery Children’s Hospital in Edmonton.
“We are releasing this information proactively, to share details of the potential risk of exposure to M. chimaera bacteria, as well as to reassure patients and families that there is an extremely low risk of infection in those who have been exposed,” said Dr. Mark Joffe, AHS Senior Medical Director of Infection, Prevention and Control.
Joffe said they have been using the manufacturer’s instruction for cleaning and maintenance of the machines, and have begun additional safety measures to decrease any risk in new surgery.
The infection sometimes takes months or years to develop and can be suspected with fever, unexplained persistent and profuse night sweats, unexpected weight loss, muscle aches, fatigue, redness or heat and pus at the incision site.
Mycobacterium chimaera is a common slow-growing organism, frequently found in soil or water. It is not transmitted from person to person. Patients with compromised immune systems, underlying lung disease, diabetes, those undergoing chemotherapy or certain invasive healthcare procedures, or receiving heart valve replacement surgery may be at greater risk of contagion. It is treated with a strong course of antibiotics.
Medical experts have indicated that patients should not cancel serious heart surgery, as the risk of not having surgery is far greater than the low risk of contracting a mycobacterium chimaera infection.
Joffe said that similar symptoms may be due to other bacterial, virus infections or health issues, but patients should contact their doctors if they have concerns.
In the 2017 June edition of the Center for Disease Control and Prevention (CDC) Emerging Infectious Diseases journal, researchers tested pathogen pathways from heater-cooler units used during cardiac surgery and determined, in spite of ultraclean air ventilations systems, that mycobacterium chimaera was present and transferred to surgical fields.
When the heater-cooler units were turned off, there was a significant decrease in particle content measured. The research indicated its limitations, but concluded that all heater–cooler units should be reliably separated from air that can gain access to sterile areas, and instruments and devices that generate drafts should be banned from the operating room.
Similar infections have also been reported in the United States and Europe.