title: Optoelectronic system for the determination of blood volume in pneumatic heart assist devices.
abstract: BACKGROUND
  The following article describes the concept of optical measurement of blood volume in ventricular assist devices (VAD's) of the pulsatile type. The paper presents the current state of art in blood volume measurements of such devices and introduces a newly developed solution in the optic domain. The objective of the research is to overcome the disadvantages of the previously developed acoustic method-the requirement of additional sensor chamber.
  
  
  METHODS
  The idea of a compact measurement system has been introduced, followed by laboratory measurements. Static tests of the system have been presented, followed by dynamic measurements on a physical model of the human ventricular system. The results involving the measurements of blood chamber volume acquired by means of an optical system have been compared with the results acquired by means of the Transonic T410 ultrasound flow rate sensor (11PLX transducer, uncertainty ±5 %).
  
  
  RESULTS
  Preliminary dynamic measurements conducted on the physical model of the human cardiovascular system show that the proposed optical measurement system may be used to measure the transient blood chamber volumes of pulsatile VAD's with the uncertainties (standard mean deviation) lower than 10 %.
  
  
  CONCLUSIONS
  The results show that the noninvasive measurements of the temporary blood chamber volume in the POLVAD prosthesis with the use of the developed optical system allows us to carry out accurate static and dynamic measurements.
authors.affiliation: Department of Optoelectronics, Silesian University of Technology, 2A Akademicka Str., 44-100, Gliwice, Poland. grzegorz.konieczny@polsl.pl.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Konieczny
authors.affiliation: Department of Optoelectronics, Silesian University of Technology, 2A Akademicka Str., 44-100, Gliwice, Poland. tadeusz.pustelny@polsl.pl.
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Pustelny
authors.affiliation: Department of Optoelectronics, Silesian University of Technology, 2A Akademicka Str., 44-100, Gliwice, Poland. maciej.setkiewicz@polsl.pl.
authors.forename: Maciej
authors.initials: M
authors.lastname: Setkiewicz
authors.affiliation: Foundation of Cardiac Surgery Development Zabrze, 345a Wolności Str., 41-800, Zabrze, Poland. mgawlik@frk.pl.
authors.forename: Maciej
authors.initials: M
authors.lastname: Gawlikowski
mesh_terms: D001811:Blood Volume Determination / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis / Q000295:instrumentation*; D006353:Heart-Assist Devices; D055096:Optical Devices; D010783:Photometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012666:Semiconductors; D012680:Sensitivity and Specificity