Scientific article

Correction of cardiac output obtained by Modelflow from finger pulse pressure profiles with a respiratory method in humans

Published inClinical science, vol. 106, no. 4, p. 371-376
Publication date2004

The beat-by-beat non-invasive assessment of cardiac output (Q litre x min(-1)) based on the arterial pulse pressure analysis called Modelflow can be a very useful tool for quantifying the cardiovascular adjustments occurring in exercising humans. Q was measured in nine young subjects at rest and during steady-state cycling exercise performed at 50, 100, 150 and 200 W by using Modelflow applied to the Portapres non-invasive pulse wave (Q(Modelflow)) and by means of the open-circuit acetylene uptake (Q(C2H2)). Q values were correlated linearly ( r = 0.784), but Bland-Altman analysis revealed that mean Q(Modelflow) - Q(C2H2) difference (bias) was equal to 1.83 litre x min(-1) with an S.D. (precision) of 4.11 litre x min(-1), and 95% limits of agreement were relatively large, i.e. from -6.23 to +9.89 litre x min(-1). Q(Modelflow) values were then multiplied by individual calibrating factors obtained by dividing Q(C2H2) by Q(Modelflow) for each subject measured at 150 W to obtain corrected Q(Modelflow) (Qcorrected) values. Qcorrected values were compared with the corresponding Q(C2H2) values, with values at 150 W ignored. Data were correlated linearly ( r = 0.931) and were not significantly different. The bias and precision were found to be 0.24 litre x min(-1) and 3.48 litre x min(-1) respectively, and 95% limits of agreement ranged from -6.58 to +7.05 litre x min(-1). In conclusion, after correction by an independent method, Modelflow was found to be a reliable and accurate procedure for measuring Q in humans at rest and exercise, and it can be proposed for routine purposes.

  • Acetylene/metabolism
  • Adult
  • Blood Pressure
  • Blood Pressure Monitoring, Ambulatory/ methods
  • Cardiac Output
  • Exercise Test
  • Fingers/ blood supply
  • Humans
  • Least-Squares Analysis
  • Male
  • Sensitivity and Specificity
  • Workload
Citation (ISO format)
TAM, Enrico et al. Correction of cardiac output obtained by Modelflow from finger pulse pressure profiles with a respiratory method in humans. In: Clinical science, 2004, vol. 106, n° 4, p. 371–376. doi: 10.1042/CS20030302
Updates (1)
ISSN of the journal0143-5221

Technical informations

Creation08/06/2010 1:47:46 PM
First validation08/06/2010 1:47:46 PM
Update time03/14/2023 3:59:30 PM
Status update03/14/2023 3:59:30 PM
Last indexation10/18/2023 11:05:01 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack