Diagnostyka stanu napełnienia sztucznej komory serca POLVAD

Niniejszy artykuł zawiera opis przeprowadzonego eksperymentu identyfikacyjnego dla sztucznej komory serca POLVAD-MEV oraz opracowanych algorytmów wykrywania stanu całkowitego napełnienia oraz wyrzutu z komory krwistej tego urządzenia. Przedstawiono metody diagnostyczne bazujące na różnych sygnałach wejściowych oraz ich implementację w programie symulacyjnym PExSim. Zawarto oraz omówiono uzyskane wyniki oraz opracowano wnioski dotyczące poszczególnych metod wyznaczania stanów granicznych napełnienia komory.

The paper presents an identification experiment for the POLVAD-MEV artificial heart and the developed detection algorithms for complete filling and full emptying the device blood chamber. In Section 1 the subject is presented and the problem of thrombus formation, as a result of incomplete range of the assist device membrane motion, is discussed. Section 2 presents the research methodology. In Subsection 2.1 the ventricle assist device construc-tion (Fig. 1) and the test bench are described. The stand consists of a hybrid model of the circulatory system [10] with attached POLVAD device and the following measuring equipment: ultrasonic flow measurements at the inlet and outlet cannula, pressure sensors at the inlet and outlet of the blood chamber and the air pressure in pneumatic drain. In Subsection 2.2 the impact of complete filling and full ejection on the transients of the measured values is dis-cussed (Fig. 2). Two algorithms for detection of complete filling and full ejection are presented. One of them is based on the analysis of pressure changes in the cannulas and pneumatic drain, the second one is based only on the pneumatic pressure variation. Section 3 presents the results of the diagnostic algorithm examination. The effectiveness of the proposed methods is compared. In the last section the obtained results are summarized and some proposals for further improvements are given when focusing on the development of diagnostic features based on analysis of the pneumatic pressure variation only.