A mathematical model approach quantifying patients' response to changes in mechanical ventilation: Evaluation in volume support

S. Larraza, N. Dey, D. S. Karbing, J. B. Jensen, M. Nygaard, R. Winding, S. E. Rees

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5 Citations (Scopus)


This paper presents a mathematical model-approach to describe and quantify patient-response to changes in ventilator support. The approach accounts for changes in metabolism (V˙O2, V˙CO2) and serial dead space (VD), and integrates six physiological models of: pulmonary gas-exchange; acid-base chemistry of blood, and cerebrospinal fluid; chemoreflex respiratory-drive; ventilation; and degree of patients' respiratory muscle-response.The approach was evaluated with data from 12 patients on volume support ventilation mode. The models were tuned to baseline measurements of respiratory gases, ventilation, arterial acid-base status, and metabolism. Clinical measurements and model simulated values were compared at five ventilator support levels.The models were shown to adequately describe data in all patients (χ2, p>0.2) accounting for changes in V˙CO2, VD and inadequate respiratory muscle-response. F-ratio tests showed that this approach provides a significantly better (p<0.001) description of measured data than: (a) a similar model omitting the degree of respiratory muscle-response; and (b) a model of constant alveolar ventilation. The approach may help predict patients' response to changes in ventilator support at the bedside.

Original languageEnglish
Pages (from-to)341-349
Number of pages9
JournalMedical Engineering and Physics
Issue number4
Publication statusPublished - 1 Apr 2015
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Biophysics
  • Biomedical Engineering

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