Biomedical Engineering Expert Discusses Infection From Heater-Cooler Device

This case involves a patient who allegedly contracted a pulmonary infection following cardiothoracic surgery. The patient in question had undergone open heart surgery in order to treat a malformation in his aorta, during which he was placed on cardio-pulmonary bypass. In addition, the patient was also attached to a heater-cooler device in order to maintain his body temperature. It was claimed that a flaw in the design of the heater-cooler device allowed bacteria to enter the surgical site during the procedure.

Question(s) For Expert Witness

1. Please describe your familiarity with the device in question or similar devices.

2. Have you ever designed or inspected such a device or a similar device?

Expert Witness Response E-065526

With two decades of research in biomechanics, medical devices, and medical instrumentation, specifically for cardiovascular surgery and perfusion during open heart surgery, as well as both industrial and academic experience with design of medical instruments and devices, I believe to have a strong background to review this case. I was the Director of Research for a major center of cardiovascular technology for several years. This school educate perfusionists (the person that controls the heart-lung machine as well as the heat-cooling exchanger during open heart surgery) and also offer a Master's program for those who are interested in heart-lung machine and cardiopulmonary bypass research. I have published research on issues with cardiovascular perfusion during open heart surgery. The heat exchanger puts the blood from the patient on the operating table undergoing open heart surgery through a series of pipes and contains fluid that serves as a temperature reservoir for heating, cooling, and temperature conservation. There is no direct contact in-between the liquids and blood in the machine. However, in these devices, the air that these liquids are in touch with is typically not sealed off from the surroundings, and bacteria can escape, causing infection problems, especially if ventilation is not appropriate for the setting. This is a generic risk with these machines, and the FDA is aware of this problem. In addition, malfunction of the device and mishandling by personnel might also be adding to the risk of adverse events leading to elevated infection rates. In my current profession, I educate students in cardiovascular fluids, cardiovascular physiology, and devices associated with heart and vascular surgery.