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Frequently Asked Questions (FAQs) about Heater-Cooler Devices

The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) have reported that a piece of equipment used to heat and cool the blood during open chest surgery has been linked to infections identified after surgery.
Q. What is a heater-cooler device?
A. A heater-cooler device is a piece of equipment used during open chest surgeries to regulate the temperature of fluids used in the procedure. There are several different brands of this equipment. This safety notice is specifically related to a heater-cooler device manufactured by Sorin (now Liva-Nova).
Q. What is the type of bacteria which may cause the risk of infection in these heater-cooler devices?
A. Mycobacterium chimaera (M. chimaera)
Q. What is Mycobacterium chimaera (M. chimaera)?
A. Mycobacterium chimaera is a type of bacteria referred to as a “nontuberculous mycobacteria (NTM);” it does not cause tuberculosis. It is often found in water or soil. It can be present in the environment, but most people do not get sick from it.
Q. What is the risk of infection with M. chimaera if this equipment was used during surgery?
A. The risk of infection is very low. The CDC estimates the risk of infection where this equipment was used as much less than 1 percent. There have been about 80 cases identified to date worldwide, in both the United States and in Europe, while hundreds of thousands of these surgeries are done every year.
Q. Why are hospitals notifying patients if the risk is low?
A. This notification is being made out of an abundance of caution to raise awareness of a potential risk of infection. The CDC recommended that hospitals who used these devices notify patients about the risk of infection despite the low risk. The notification is intended to help increase the chances that potentially affected patients are alerted and seek medical care if needed. The following BJC Hospitals used heater-cooler devices during the time period where the risk has been identified:
  • Barnes-Jewish Hospital
  • Boone Hospital Center
  • Christian Hospital
  • Missouri Baptist Medical Center
Q. How did the bacteria get into the devices?
A. The results of investigations in Europe and by the CDC suggest that the bacteria got into the devices at the manufacturer during production. According to the findings of these investigations, the bacteria was found in the production line and water supply at the facility where the devices were made. These bacteria are difficult to remove from the device, even when it is carefully and frequently cleaned according to the manufacturer’s recommendations.
Q. How would a patient possibly be exposed to M. chimaera during surgery?
A. A patient who underwent an open chest surgery with an affected heater-cooler device may have been exposed to NTM-contaminated mist from the device’s water tanks which was dispersed into the air of the operating room through a process called aerosolization. This creates the potential for the aerosolized bacteria to come into contact with the patient through the open chest during the surgical procedure.
Q. How long can it take for a person to develop signs or symptoms of infection after the surgery?
A. The bacteria that was found in these devices grows very slowly. This type of infection may take months or even a few years to develop after an open chest surgery if the patient was exposed during the surgery.
Q. If a person has this bacteria, can he spread it to others?
A. No. M. chimaera cannot spread from person to person.
Q. Has BJC HealthCare found any surgery patients at BJC hospitals who have gotten this infection after the surgery?

A. No. BJC reviewed records from patients who had open chest procedures back to 2010, and no M. chimaera-associated infections were found.

Q. What are the signs and symptoms of an infection with M. chimaera?
A. Symptoms of M. chimaera infections are general and usually last for at least several weeks. Symptoms may include:
  • Drenching night sweats
  • Muscle aches
  • Unintended weight loss
  • Unexplained persistent or recurrent fever
Some patients have developed heart valve infections without another clear cause or have been told they have sarcoidosis, which are abnormal collections of inflammatory cells that form lumps known as granulomas.
No cases have been identified in patients without symptoms.
Q. What should I do if I have any of these symptoms?
A. If you are having symptoms and you have had an open chest surgical procedure, you should discuss your symptoms with your primary care provider who can help determine any next steps related to detection and treatment, if needed. If you received a notification letter and are having symptoms, you may also take the patient notification letter to your primary care provider, your cardiologist, or your surgeon for evaluation and to discuss if any testing is needed.
Q. What should I do if I DO NOT have any of these symptoms?
A. If you have no symptoms, there is no action needed. If you received a notification letter, take it to your next appointment with your family doctor or primary care provider so they have a record of it.
Q. I don’t have any symptoms, but I’m still very worried. What should I do?
A. We understand that you and your family might have additional questions or concerns about this matter. Your family doctor or primary care provider can help to answer your questions. Also, BJC HealthCare is providing a Call Center that will be available from 8 a.m. to 4 p.m. (CST) Monday through Friday. The Call Center can answer general questions from patients and family members. The Call Center cannot provide specific medical advice. The Call Center phone number is 314-747-1984 or 888-747-1984. You can also email questions to [email protected] and anticipate an answer within two (2) business days.
Q. Can M. chimaera infections be treated?
A. Yes. There are antibiotics that are effective against M. chimaera. Treatment can be discussed with your health care provider if you are diagnosed with an infection.
Q. Is there a test that can tell if I was exposed to the bacteria?
A. No. There is no general test that can determine if you were exposed to M. chimaera. If you are having symptoms and have had open chest surgery, your health care provider may order certain tests based on a medical assessment. If your provider determines that a blood test is needed to look for infection with M. chimaera, the results of that test may take two months to come back, since the bacteria grows very slowly. No cases have been identified in patients who are having no symptoms.
Q. Is there medication I can take to prevent getting the infection?
A. No. The risk of infection is very low. Studies do not show that taking an antibiotic will help prevent an infection with M. chimaera. Taking antibiotics unnecessarily may produce unwanted side effects. Treatment can be discussed with your health care provider if you are diagnosed with an infection.
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