Warnings for the Stöckert 3T Heater-cooler System. The Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) have both issued infection warnings for the Stöckert 3T heater-cooler system used to regulate the patient’s body temperature during surgery.
The agencies have warned specifically about the bacterial infection Mycobacterium chimaera that has been transmitted to patients. The Stöckert 3T heater-cooler system helps regulate a patient’s body temperature during surgery for better patient outcomes, but the unit can transmit bacteria into the air, endangering the patient, especially during open-chest cardiac surgeries.
A recent lawsuit filed against LivaNova PLC (formerly Sorin Group Deutschland GmbH), alleges that LivaNova failed to warn hospitals and doctors of the increased risk of infections, according to Philly.com.
The FDA reports that Sorin had received complaints about patient deaths related to nontuberculous mycobacterium (NTM) and the devices since January 2014. (M. chimaera is a type of NTM that can cause serious illness or death). Parker Waichman notes that another surgical warming device, the Bair Hugger warming blanket is also alleged to spread infection, in particular in patients undergoing joint replacement surgery.
The plaintiff in the recent lawsuit, Kenneth, underwent cardiac surgery in December 2014 at Penn Presbyterian Medical Center in Pennsylvania. The procedure was successful but in May 2015 he suffered a stroke, which he claims was caused by slow-growing bacteria he was exposed to during the procedure. In March 2016, a Penn physician told him his infection likely came from the 3T heater-cooler.
Exposed To Deadly Bacteria
From October 2013 to December 2015, 1,100 patients at Penn Presbyterian Medical Center were potentially exposed to deadly bacteria through the heater-cooler system used during their surgeries. Four of those patients tested positive for nontuberculous mycobacteria.
LivaNova and the hospitals where the 3T system was used are facing lawsuits that allege defective products and negligence. As of October 2016, hospitals in Pennsylvania, Iowa and Michigan reported infections. At-risk patients at the following hospitals were notified. The number of at-risk patients, the number identified with NTM infections and the inclusive dates of the surgeries are given in parentheses.
- WellSpan York Hospital (1,300 notified; 12 cases; 10/1/11 to 7/24/15)
- Penn State Hershey Hospital (2,300 notified; 5 cases; 11/5/11 to 11/5/15)
- Penn Presbyterian Medical Center (1,100 notified; 4 cases; 10/1/13 to 12/17/15)
- University of Iowa (1,500 notified; 3 cases; 1/1/12 to 1/22/16)
- Mercy Medical Center in Iowa (2,600 notified; 2 cases; 7/1/12 to 7/1/16)
- Spectrum Health Medical Center in Michigan (4,500 notified; 2 cases; 1/1/12 to 11/10/15)
Nationwide, as many as 500,000 patients could be at risk for infection, the Washington Post reports.
The Stöckert 3T heater-cooler is a device used during heart surgeries to keep the patient’s organs and blood at the proper temperature during the procedure. Keeping an ideal body temperature during surgery improves outcomes.
Heater-cooler devices include water tanks that provide temperature-controlled water to heat exchangers or blankets, which then cool or warm the patient’s body. Water in the circuits does not directly come into contact with the patient, but contaminated water can aerosolize and transmit bacteria through the device’s exhaust vent into the environment and to the patient.
The Stöckert 3T warming-cooling device has been implicated in nontuberculous mycobacteria infections caused by the M. chimaera bacteria. M. chimaera has been directly linked to a contamination in the manufacturing of the Stöckert 3T Heater-Cooler System (3T) by Sorin Group Deutschland GmbH.
Swiss researchers reported in the October 2016 issue of Emerging Infectious Diseases that heater-cooler units seem to provide favorable environmental conditions for growth of NTM, in particular M. chimaera. “An intensified cleaning and disinfection protocol failed to prevent growth of NTM entirely but succeeded in preventing detectable aerosolization of M. chimaera.
The contamination status of HCUs seems to be influenced by the intensity of maintenance, especially frequency of water changes.” Researchers have found that NTM could become airborne through a vent in the device and land in the chest cavity during surgery.
The FDA and CDC report that the Sorin 3T heater-cooler devices were allegedly contaminated with the Mycobacterium chimaera during manufacture in Germany. The contamination was discovered in September 2014 at the manufacturing facility. Testing in July 2015 showed that the problem had been resolved. Heater-cooler systems manufactured after September 2014 are not linked to the harmful bacteria.
To avoid introducing mycobacteria into the system, the FDA says tap water should never be used to fill, rinse, or top off the 3T water tanks. In addition, the heater-cooler’s exhaust vent should be directed away from the surgical field to reduce the risk of exposing the patient to bacteria from the exhaust.
In July 2015, the FDA announced a Class II recall of the Sorin 3T System. The FDA announcement noted the “potential colonization of organisms, including Mycobacteria, in Stöckert Heater Cooler Devices, if proper disinfection and maintenance is not performed according to instructions.
A Class II recall is the FDA’s intermediate recall category. Use of the product “may cause temporary or medically reversible adverse health consequences,” but the probability of serious health consequences is remote.
Nontuberculous mycobacterium infections can sometimes be successfully treated with a prolonged course of antibiotics and removal of infected tissue. But in some cases, treatment is unsuccessful and patients die because of the infection.
The CDC advises heart surgery patients experiencing the following symptoms to seek medical attention because the symptoms could be linked to a bacterial infection:
- night sweats
- muscle aches
- weight loss
- unexplained fever