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Updated: Jul 10, 2026

Inspiratory Muscle Training as an Adjunct to the Treatment of Weaning Failure in Critically Ill Patients: A Practical Guide
Published on: January 30, 2026
Information flow to assess cardiorespiratory interactions in patients on weaning trials
M Vallverdú1, O Tibaduisa, F Clariá
1Dep. ESAII, Centre for Biomedical Engineering Research, Technical University of Catalonia, Barcelona, Gargallo, 5, 08028 Barcelona, Spain. Montserral.Vallverdu@upc.edu
Abstract:
Nonlinear processes of the autonomic nervous system (ANS) can produce breath-to-breath variability in the pattern of breathing. In order to provide assess to these nonlinear processes, nonlinear statistical dependencies between heart rate variability and respiratory pattern variability are analyzed. In this way, auto-mutual information and cross-mutual information concepts are applied. This information flow analysis is presented as a short-term non linear analysis method to investigate the information flow interactions in patients on weaning trials. 78 patients from mechanical ventilation were studied: Group A of 28 patients that failed to maintain spontaneous breathing and were reconnected; Group B of 50 patients with successful trials. The results show lower complexity with an increase of information flow in group A than in group B. Furthermore, a more (weakly) coupled nonlinear oscillator behavior is observed in the series of group A than in B.
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