Contaminated Heater-Cooler Devices Questions and Answers
On Oct. 13, the CDC recommended that hospitals across the country using a surgical device for open heart surgery inform patients of a possible risk of developing a treatable mycobacterium infection due to a potential contamination in the device’s manufacturing process.
UAB Hospital has reviewed extensive records of patients who underwent this procedure over the last six years and identified none who tested positive for any mycobacterium infection. We have consistently met or exceeded recommended monitoring and maintenance on these devices for years, and prior to the CDC recommendation, we proactively refurbished our devices to address the concern. We will maintain our stringent monitoring and maintenance, as well as compliance with CDC and FDA recommendations.
Any patients who have had an open heart surgery at UAB in the last four years will receive information by mail. Those who feel they may have symptoms associated with infections should contact their primary care provider or call UAB at 205-801-7078.
Q1. What is the situation?
A. The U.S. Centers for Disease Control and Prevention (CDC) has notified all hospitals of a potential exposure to bacteria in patients who have undergone open chest cardiac surgery using a heart/lung bypass machine. The bacteria have been linked to heater-cooler devices used during these surgical procedures.
Q2. What type of bacteria is involved?
A. The bacterium is called Nontuberculous Mycobacteria chimaera (M. Chimaera), or NTM. It grows slowly and is commonly found in soil and water, including tap water. It is usually not harmful to humans, and typically only rarely has caused infections in patients with weakened immune systems. However, patients who have had open-chest heart surgery with bypass may have become exposed to these bacteria during their procedure, and could be at risk of infection.
Q3. What is the risk of infection?
A. Overall, the risk is thought to be very low. For patients who have had one of these surgeries, the chances of getting this infection are very low. CDC estimates the risk to be less than 1 percent. Of the more than 4,500 patients who had open-heart surgery at UAB Hospital in the last six years, we are aware of no patients who developed this infection.
Q4. Why are we contacting patients?
A. As patients of UAB Hospital, their wellbeing is our top priority. The CDC has updated its recommendations to inform all patients about the potential risk for infection even in facilities like UAB where no infection has been found. Although the risk of developing an NTM infection after cardiac surgery is very low, we want to make sure that our open chest heart surgery patients are aware of this issue, and understand that we have resources available to our patients who may have questions or health concerns.
Q5. What types of surgeries place patients at risk for this infection?
A. Only open-chest heart surgeries using a heart/lung bypass machine carry this very low risk. This includes coronary artery bypass graft (CABG) surgeries, valve surgeries, and surgical procedures involving the thoracic aorta.
Q6. What if I had another type of heart surgery?
A. Patients who had other, less invasive heart procedures – such as stents, pacemakers, defibrillators and ablations – or minimally invasive cardiac surgery procedures such as transcatheter aortic valve replacement, or TAVR, are not at risk because the heater-cooler device is not used for these procedures.
Q7. Has this happened at other hospitals?
A. Yes. Although we have not identified any cases at UAB, there have been a small number of cases documented in the United States and Europe. In the United States, federal health authorities, including the CDC and Food and Drug Administration (FDA) have issued health advisories to all hospitals.
Q8. What action is UAB taking to protect patients?
A. We have always consistently followed or exceeded manufacturer guidelines for disinfecting and maintaining heater-cooler devices across our health system. We believe that the potential risk of exposure to NTM bacteria has been effectively addressed. In addition to notifying our patients, we have created a hotline (205-801-7078) to provide our patients with additional information, screening, and appointments, if needed.
Q9. What are the symptoms of an NTM infection?
A. Symptoms of an NTM infection include:
These symptoms are not specific for NTM and can be due to many other causes, but NTM should be considered if you had possible exposure from open-heart surgery. NTM infection may take a long time to develop after potential exposure – from a few weeks up to four years. Therefore, those who may have been exposed to NTM should continue to look for symptoms and see their clinician for further evaluation if any develop.
Q10. Is this infection treatable?
A. Yes, there are effective antibiotic treatments available for this infection.
Q11. If I have been exposed or develop an NTM infection, is my family at risk of getting the infection?
A. No, the bacteria cannot be spread to others from an infected patient. It is not contagious. Also, it is important to keep in mind that NTM is common in soil and water but rarely makes healthy people sick.
Q12. Can I find out whether I’m infected?
A. If you do not have symptoms, you do not require testing. Because the bacterium grows slowly, it can take several months or years for symptoms of infection to develop. If you have or develop symptoms, it is important for your clinician to know in order to evaluate you and if needed arrange for additional testing.
Q13. 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.
Q14. Should everyone who was exposed to these devices during open-heart surgery receive antibiotics just in case?
A. 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.
Q15. How long does it take to find out if an infection is being caused by NTM?
A. M. chimaera is a slow-growing species of NTM that can take eight weeks and sometimes longer to grow and allow final identification.
Q16. What is a heater-cooler device and how might it be related to this problem?
A. A heater-cooler device is used during open-heart surgeries to warm or cool a patient’s blood as part of their usual surgical care. It is never in direct contact with the patient or the patient’s blood. There is a water reservoir inside the device. NTM can grow in the water in heater-cooler devices. During use, some of the water evaporates and enters the air in the operating room. It is believed that the NTM bacteria may be put in to the air by the heater-cooler device, and can then possibly enter the patient’s open chest during the procedure.
Q17. How do you think the devices got contaminated?
A. 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 in Germany.
Q18. What do I need to do now?
A. Call us at 205-801-7078 with any questions or concerns. Our call center will be open 8 am – 5 pm Mondays – Fridays. We will ask you a few screening questions, answer your questions, and if necessary, we can arrange an appointment with a medical provider.