A PERFUSION SYSTEM WITH MONITORING DEVICES FOR OPEN-HEART SURGERY

Abstract

The recent efforts on improving the physiological aspects of heart-lung perfusion techniques concern mainly two areas connected with the extracorporeal system. These are the reduction of priming volume required in the oxygenator and the requirement for a monitored control of the blood's gas exchange parameters to maintain a more physiological perfusion during bypass. This thesis presents a contribution in these areas. First, this thesis presents a heart-lung system specifically designed to operate in conjunction with an improved Kay Cross disc oxygenator. This oxygenator requires exclusive control features, not generally available in commercial units, since it performs the dual function of heat-exchanging and oxygenating the blood. This dual function provides an overall reduction in the systems priming volume. Secondly, a unique Rotating Cylinder oxygenator design, demonstrating a 1/3 priming volume requirement over the equivalent Kay Cross model, is presented and evaluated for clinical suitability. Finally, this thesis describes a constant withdrawal system, employing commercially available electrodes, whereby simultaneous and continuous monitoring of the blood gas-exchange parameters can be monitored. Specific tests were performed whereby the performance of the electrodes in the system were evaluated under the constant withdrawal conditions required to continuously monitor a heart-lung bypass.