title: Evaluation of flow rate estimation method for rotary blood pump with chronic animal experiment.
abstract: Rotary blood pumps are expected to be used as an implantable ventricular assist device (VAD). In the VAD system, flow rate is important for monitoring of the state of a recipient and for automatic control to maintain appropriate blood perfusion. To obtain flow rate of the pump without any sensors, we proposed a method of estimating flow rate with supplied power and rotational speed using a time series model. To evaluate the accuracy of the proposed estimation method from the aspect of long-term use, we implanted NEDO PI Gyro pumps in a calf and performed a chronic animal experiment. Flow rate, supplied power and rotational speed were measured until post operation day (POD) 63, and the estimated flow rate was compared with the measured one. We confirmed that waveforms of the measured flow rate was sufficiently similar to the measured one, and correlation between them was higher than 0.9 in all the datasets. On the other hand, the root mean square error increased after 15 days. This error was probably due to the change in physiological condition, the operating point of the pump, or mild intima formation.
authors.affiliation: Member, IEEE, Graduate School of Engineering, Tohoku University, 6-6-05, Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan (phone: +81-22-795-7130; fax +81-22-263-9163; e-mail: ogawa@yoshizawa.ecei.tohoku.ac.jp).
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ogawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshizawa
authors.forename: Akira
authors.initials: A
authors.lastname: Tanaka
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Abe
authors.forename: Paul
authors.initials: P
authors.lastname: Olegario
authors.forename: Tadashi
authors.initials: T
authors.lastname: Motomura
authors.forename: Hisashi
authors.initials: H
authors.lastname: Okubo
authors.forename: Takeshi
authors.initials: T
authors.lastname: Oda
authors.forename: Toshiya
authors.initials: T
authors.lastname: Okahisa
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Nose