Optimierung der venösen druckmessung am Jenaer universalperfusionssystem (hybrid-herz-lungen-maschine)

The development of the Jena Universal Perfusion System enables new standards in the modern cardiac surgery. Universal versatility and the avoiding of blood transfusions and complications are the most important pros of this hybrid heart-lung machine, beside the automatic low pressure compensation by the help of volume balance. These machines use an active drainage like the rising low prime systems. The suction in the venous tube is the driving force of the circulation. To reach the needed suction effect, centrifugal or diagonal pumps are used. They can reach pressures down to -600 mmHg, according to their capability. Here are the risks that are important to avoid. For this a safe pressure monitoring is absolutely essential. Scenarios like cavitation effects or the influx of air at sensible system locations causes neurological complications like air embolisms. It is important to monitor and, better yet, to avoid these scenarios. To monitor short negative pressure peaks, which can be an indication of a suction from the cannulas, a measuring system with a variable and high resolution was developed. With this measuring system the tests of the flexible membrane, which is the main optimization, were possible. The whole point of the membrane is to build a boundary between the pressure sensing tube and the extracorporeal circulation. This is necessary to avoid an influx of blood in the pressure sensing tube (thrombus!) and an influx of air in the extracorporeal circulation, too. To sum up, the optimization of the venous low pressure measurement at the Jena Universal Perfusion Systems was the main part of my bachelor thesis.