Computational and Mathematical Methods in Medicine
Volume 2013 (2013), Article ID 505417, 17 pages
http://dx.doi.org/10.1155/2013/505417
Research Article

Evaluation of a Model-Based Hemodynamic Monitoring Method in a Porcine Study of Septic Shock

1Department of Mechanical Engineering, Centre of Bioengineering, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
2Hemodynamic Research Laboratory, University of Liege, Liege, Belgium
3Department of Intensive Care, Christchurch Hospital, Christchurch, New Zealand

Received 16 October 2012; Revised 22 January 2013; Accepted 6 February 2013

Academic Editor: Jacek Waniewski

Copyright © 2013 James A. Revie et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Introduction. The accuracy and clinical applicability of an improved model-based system for tracking hemodynamic changes is assessed in an animal study on septic shock. Methods. This study used cardiovascular measurements recorded during a porcine trial studying the efficacy of large-pore hemofiltration for treating septic shock. Four Pietrain pigs were instrumented and induced with septic shock. A subset of the measured data, representing clinically available measurements, was used to identify subject-specific cardiovascular models. These models were then validated against the remaining measurements. Results. The system accurately matched independent measures of left and right ventricle end diastolic volumes and maximum left and right ventricular pressures to percentage errors less than 20% (except for the 95th percentile error in maximum right ventricular pressure) and all . An average decrease of 42% in systemic resistance, a main cardiovascular consequence of septic shock, was observed 120 minutes after the infusion of the endotoxin, consistent with experimentally measured trends. Moreover, modelled temporal trends in right ventricular end systolic elastance and afterload tracked changes in corresponding experimentally derived metrics. Conclusions. These results demonstrate that this model-based method can monitor disease-dependent changes in preload, afterload, and contractility in porcine study of septic shock.