Cardiac Surgery Contaminated Heater/Cooler Devices

You may have seen recent news stories about a risk of a rare infection in patients who have undergone heart surgery. The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) are investigating reports that a device used to heat and cool the blood during open heart surgery has been linked to a rare bacterial infection caused by Mycobacterium chimaera, a type of bacteria known as nontuberculous mycobacterium (NTM). New information indicates that these heater/cooler devices may have been contaminated with the bacteria when they were manufactured.

Download a copy of the letter that was sent to patients.

Frequently Asked Questions (FAQs)

What is the risk of infection?

Overall, the risk is thought to be very low. In hospitals where at least one infection has been identified, the risk of infection was between about 1 in 100 and 1 in 1,000 patients. Initial information suggests that patients who had prosthetic implants are at higher risk. It is possible that not all of the devices introduced these bacteria into the operating room or exposed patients.

Does CHOP use these heater/cooler devices?

Yes, this device has been used during open heart surgery at Children's Hospital of Philadelphia (CHOP). However, we have already taken extensive measures to ensure close monitoring, maintenance, and proper cleaning/disinfection of these heater/cooler devices. We performed sampling of the devices and have never found Mycobacterium chimaera.

Has CHOP had any patients with Mycobacterium chimaera infections?

No. We perform ongoing surveillance and monitoring for infections and zero patients who have had open heart surgery at CHOP have developed this infection.

How is CHOP responding to this?

In accordance with CDC recommendations, we are notifying patients who have undergone open heart surgery, or their parents, about the potential infection risk. We have already taken extensive measures to ensure close monitoring and proper cleaning/disinfection of these heater/cooler devices and have never identified Mycobacterium chimaera from our machines. However, because of the reported infection risk associated with these devices, we have identified an alternative device for heating and cooling during surgery and will be replacing all of the current equipment as soon as the new devices are available.

How long does it usually take for these infections to show up?

A. NTM are slow-growing bacteria and infections may take months to develop. Cases associated with this device have been diagnosed within months and up to several years after an open heart surgery involving heater/cooler unit exposure. The range of time reported in patients with this infection has been months up to 3.6 years after surgery.

Can a person who develops one of these NTM infections spread it to others, such as family members?

No, the bacteria cannot be spread to others from an infected patient. Also, it is important to keep in mind that NTM is common in soil and water, but rarely makes healthy people sick.

Should everyone who was exposed to these devices during open heart surgery receive antibiotics just in case?

The risk that patients will develop an infection following exposure to a contaminated heater/cooler unit is very low. There is also no evidence that giving antibiotics just prior or during surgery with a potentially contaminated heater/cooler device will prevent infection. Although antibiotics can be life-saving drugs, there is no antibiotic treatment available to ward off this specific infection, and antibiotics are also not without risk themselves. Antibiotics put patients at risk for allergic reactions and a potentially deadly diarrheal infection caused by the bacteria Clostridium difficile. Antibiotic use is also a key driver of antibiotic resistance, which can put patients at risk for antibiotic-resistant infections later.

How long does it take to find out if an infection is being caused by NTM?

M. chimaera is a slow-growing species of NTM that can take eight weeks and sometimes longer to grow and allow final identification.

Why are these infections so deadly?

Symptoms of infection can take months to develop, and are often general and nonspecific. As a result, diagnosis of these infections can be missed or delayed, sometimes for years, making these infections more difficult to treat. Clinicians may not immediately consider an NTM diagnosis. Delayed diagnosis can result in more widespread disease in a patient. This, combined with underlying health problems such as heart disease can make these infections difficult to treat.

How do you think the devices got contaminated?

NTM is common in water and soil. Recent CDC findings are consistent with previous reports suggesting that the heater/cooler units were contaminated during production. Testing conducted by the manufacturer in August of 2014 found M. chimaera contamination on the production line and water supply at the 3T manufacturing facility.

Have these devices ever been recalled? Why aren't they being recalled now?

In 2015, the manufacturer recalled the instructions for use, but not the device itself. Information provided by the manufacturer reminded users that while water from the device itself is not intended to contact the patient directly, under certain circumstances, due to fluid leakage and/or aerosolization, NTM could reach a patient's surgical site. Heater/cooler devices are critical for life-saving surgery. A national recall could result in patients not getting life-saving surgeries that are needed now.

More information

For more information or you have any questions, please call 215–590-0300 or contact us online.