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On-line parameter identification of systemic circulation using the delta operator.

Ryo Kosaka·Yoshiyuki Sankai·Tomoaki Jikuya·Takashi Yamane·Tatsuo Tsutsui
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Abstract

To develop effective medical care with the artificial heart, we propose a new method, on-line parameter identification of the systemic circulation using the delta operator which can calculate the time-varying and unmeasured hemodynamics of the internal human body from some measured data: aortic pressure and total flow in real time. This method consists of first, a dynamic physiological model which is configured with the physiological parameters Ca (aortic compliance) and Rp (total peripheral resistance); and second, a system identification method using the delta operator. In the computer simulation study, we could confirm the effectiveness to identify the physiological parameters. In animal experiments with a left ventricular assist system, the physiological parameters, Ca = 1.8 (ml/mm Hg) and Rp = 0.8 (mm Hg s/ml), could be identified on-line.

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Adaptation, PhysiologicalAlgorithmsAnimalsBlood Flow VelocityBlood PressureComputer SimulationHeart, ArtificialHemodynamicsModels, CardiovascularJournal Article

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Ryo Kosaka, Yoshiyuki Sankai, Tomoaki Jikuya, Takashi Yamane, Tatsuo Tsutsui. 2002. On-line parameter identification of systemic circulation using the delta operator.. https://doi.org/10.1046/j.1525-1594.2002.06931_5.x

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