title: In-vivo validation of a new non-invasive continuous ventricular stroke volume monitoring system in an animal model.
abstract: BACKGROUND
  Recently, a non-invasive, continuous ventricular stroke volume monitoring system using skin electrodes has been developed. In contrast to impedance-based methods, the new technique (ventricular field recognition) enables measurement of changes in ventricular volume. A prototype using this new method was built (the hemologic cardiac profiler, HCP) and validated against a reference method in a pig model during variations in cardiac output.
  
  
  METHODS
  In six Dalland pigs, cardiac output was simultaneously measured with the HCP (CO-HCP), and an invasive ultrasonic flow-probe around the ascending aorta (CO-FP). Variations in CO were achieved by change in ventricular loading conditions, cardiac pacing, and dobutamine administration. Data were analysed according to Bland-Altman analysis and Pearson's correlation.
  
  
  RESULTS
  Pearson's correlation between the CO-HCP and the CO-FP was r = 0.978. Bland-Altman analysis showed a bias of - 0.114 L/minute, and a variability of the bias (2 standard deviations, 2SD) of 0.55 L/minute.
  
  
  CONCLUSIONS
  The results of the present study demonstrate that CO-HCP is comparable to CO-FP in an animal model of cardiac output measurements during a wide variation of CO. Therefore, the HCP has the potential to become a clinical applicable cardiac output monitor.
authors: Department of Medical Technology and Clinical Physics, University Medical Center Utrecht, 100 Heidelberglaan, Utrecht 3584 CX, The Netherlands. m.konings@umcutrecht.nl
authors: Maurits K
authors: MK
authors: Konings
authors: Paul F
authors: PF
authors: Grundeman
authors: Henk G
authors: HG
authors: Goovaerts
authors: Maarten R
authors: MR
authors: Roosendaal
authors: Imo E
authors: IE
authors: Hoefer
authors: Pieter A
authors: PA
authors: Doevendans
authors: Frank E
authors: FE
authors: Rademakers
authors: Wolfgang F
authors: WF
authors: Buhre
mesh_terms: D000818:Animals; D005260:Female; D023421:Models, Animal; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods*; D009426:Netherlands; D013318:Stroke Volume / Q000502:physiology*; D034421:Sus scrofa; D016276:Ventricular Function / Q000502:physiology*