A rare infection contracted during cardiothoracic surgery has struck three Philadelphia patients. A fourth has tested positive for the bacteria that causes the infection but currently shows no symptoms.
The illness, caused by bacteria known as mycobacteria, has many throughout the healthcare industry questioning the safety of heater-cooler devices. The heater-cooler, essentially a blanket with tubes running through it, uses temperature-controlled water to heat or cool a heart surgery patient to the ideal temperature for his or her procedure. Other types of heater-coolers are also used to regulate the temperature of a patient’s blood as it passes through a bypass machine.
The heater-cooler is a closed system, meaning that no water ever makes contact with the patient’s body or blood. For this reason, it was believed that the heater-cooler posed no threat to the patient’s safety. This assumption had to re-examined, however, after heart surgery patients began falling ill with bacterial infections after their procedures.
After an extensive research effort, the culprit was found to be the heater-cooler. The question was why.
While the heater-cooler is a closed system, it does contain various mechanical parts used to circulate the water through the blanket. An exhaust fan is also housed within the unit, used to prevent it from overheating. Scientists discovered that contaminated water could make contact with these internal parts, pool, and contribute to the growth of bacteria. That bacteria would then be aerosolized and spread throughout the surgical suite once the exhaust fan turned on.
Under normal circumstances, these bacteria pose no threat to a human. In fact, you’re likely exposed to them every day in things as simple as your tap water. But to a patient with a compromised immune system that is already dealing with the physical trauma of open-heart surgery, the smallest, simplest infection can become life-threatening.
The Philadelphia infections are, so far, all tied to Penn Presbyterian Medical Center. Three patients are being treated by Penn physicians while the fourth is being treated elsewhere. These four contribute to the total of at least 20 such infections found throughout Pennsylvania. Further complicating matters is the length of time it takes for the bacteria to grow. In some cases, symptoms can take months or years to manifest once a patient has been infected.
Patients who have undergone cardiothoracic surgery are urged to keep an eye out for symptoms of mycobacteria infection and to contact their doctors immediately if they are experiencing any of them.
