Title
Hierarchical parameter identification in models of respiratory mechanics.
Abstract
Potential harmful effects of ventilation therapy could be reduced by model-based predictions of the effects of ventilator settings to the patient. To obtain optimal predictions, the model has to be individualized based on patients' data. Given a nonlinear model, the result of parameter identification using iterative numerical methods depends on initial estimates. In this work, a feasible hierarchical identification process is proposed and compared to the commonly implemented direct approach with randomized initial values. The hierarchical approach is exemplarily illustrated by identifying the viscoelastic model (VEM) of respiratory mechanics, whose a priori identifiability was proven. To demonstrate its advantages over the direct approach, two different data sources were employed. First, correctness of the approach was shown with simulation data providing controllable conditions. Second, the clinical potential was evaluated under realistic conditions using clinical data from 13 acute respiratory distress syndrome (ARDS) patients. Simulation data revealed that the success rate of the direct approach exponentially decreases with increasing deviation of the initial estimates while the hierarchical approach always obtained the correct solution. The average computing time using clinical data for the direct approach equals 4.77 s (SD  =  1.32) and 2.41 s (SD  =  0.01) for the hierarchical approach. These investigations demonstrate that a hierarchical approach may be beneficial with respect to robustness and efficiency using simulated and clinical data.
Year
DOI
Venue
2011
10.1109/TBME.2011.2166398
IEEE Trans. Biomed. Engineering
Keywords
Field
DocType
diseases,iterative methods,parameter estimation,patient treatment,pneumodynamics,viscoelasticity,acute respiratory distress syndrome patients,clinical data,hierarchical parameter identification,iterative numerical method,respiratory mechanics,robustness,ventilation therapy,viscoelastic model,Hierarchical models,models of respiratory mechanics,parameter identification,robustness
Data modeling,Direct method,Mathematical optimization,Computer science,Identifiability,Iterative method,A priori and a posteriori,Correctness,Robustness (computer science),Estimation theory
Journal
Volume
Issue
ISSN
58
11
1558-2531
Citations 
PageRank 
References 
5
0.65
5
Authors
5
Name
Order
Citations
PageRank
C Schranz1113.53
C Knöbel251.32
J Kretschmer3113.74
Z Zhao451.66
Knut Möller55934.75