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An automatic flow controller for a centrifugal blood pump.

T Beppu·K Seo·Y Imai·Y Takanashi·S Hoshino·J Ohta·M Aoki·S Uchita·S Suzuki·Y Tajima·N Tooyama·Y Fukui
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Abstract

To regulate the perfusion flow rate of a centrifugal blood pump, a microcomputer controller was developed. The computer monitored the flow rate of the pump with an electromagnetic flowmeter or an ultrasonic pulse Doppler flowmeter, rotational speed of the pump, aortic pressure, and the amount of blood in a reservoir. A discrete integral controller with a control interval of 1 s was adopted for the controller. For the safety of the control system, we added functions for detecting a clamp on the tubing, a dislocation of the flow sensor, or an inverse direction of the flow sensor. During a standby period, the computer calculated the rotational speed from aortic pressure to minimize the forward or the backward flow at the start of the pump perfusion. The automatic flow controller was used on 5 patients during cardiac operations and maintained the flow rate within +/-6% of the set point.

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AlgorithmsAnimalsBlood Flow VelocityBlood PressureBlood VolumeCardiopulmonary BypassCentrifugationChild, PreschoolComputer SimulationDogsElectromagnetic PhenomenaEquipment SafetyFemaleHeart-Assist DevicesHumansLaser-Doppler FlowmetryMaleMicrocomputersModels, BiologicalPerfusionReproducibility of ResultsRheologyUltrasonography, Doppler, PulsedJournal ArticleResearch Support, Non-U.S. Gov't

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T Beppu, K Seo, Y Imai, Y Takanashi, S Hoshino, J Ohta, M Aoki, S Uchita, S Suzuki, Y Tajima, N Tooyama, Y Fukui. 1997. An automatic flow controller for a centrifugal blood pump.. https://doi.org/10.1111/j.1525-1594.1997.tb03712.x

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