Entwicklung und Validierung eines Testsystems zur Evaluierung der gerinnungsaktivierenden Potenz von Bauchtüchern

Abstract

The background of this thesis are clotting problems caused by green abdominal swabs during cardiac surgery supported by heart lung machines. Amongst all surgical departments cardiac surgery poses an exception regarding hyper-coagulating abdominal swabs, since patients are pre-operatively medicated with heparin while surgery is performed without the use of a cell saver. Thus excessive blood clotting resulting from faulty abdominal swabs leads to thrombo-embolic complications. The goal was the development and validation of an in-vitro clotting test to evaluate the blood coagulation of abdominal swabs with hyper-coagulant potency. During the tests samples of various batches of abdominal swabs with heparinized human blood from 100 donors were incubated on a shaking plate for 30 minutes at 37°C and then examined micro- and macroscopically for blood clots and evaluated on the basis of a dichotomized evaluation system. Additionally SEM (scanning electron microscopy) images were made and the ACT (activated clotting times) measured. The goal of this prospective study was met. It can be assumed that with the newly developed test system eleven donors are needed to detect a swab with hyper-coagulating potential with a probability of 95% in 25% of donors. This test provides a safe preclinical testing method to detect abdominal swabs with hyper-coagulant potential. Consequently, it makes an important contribution in the future to minimize the risk of thrombo-embolic complications during cardiac surgery supported by heart lung machines.