Lung mechanics - airway resistance in the dynamic elastance model
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The selection of optimal positive end-expiratory pressure (PEEP) levels during mechanical ventilation therapy of patients with acute respiratory distress syndrome (ARDS) remains a problem for clinicians. A particular mooted strategy states that minimizing the energy transferred to the lung during mechanical ventilation could potentially be used to determine the optimal, patient-specific PEEP levels. Furthermore, the dynamic elastance model of pulmonary mechanics could possibly be applied to minimize the energy by localization of the patients’ minimum dynamic elastance range. The sensitivity of the dynamic elastance model to variance in the airway resistance was analyzed. Additionally, the airway resistance was determined by using three other established identification methods and was compared to the constant resistance obtained by the dynamic elastance model. For increasing PEEP, the alternative identification methods showed similar decreasing trends of the resistance during inspiration. This declining trend is apparently an exponential decrease. Results showed that the constant airway resistance, presumed by the dynamic elastance model, has to be rechecked and investigated.
KeywordsLung mechanics Physiological modelling First order model Dynamic elastance model Mechanical ventilation Airway resistance
This work was partially supported by the EU (eTime, Grant FP7-PIRSES 318943).
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Conflict of interest
The authors declare that they have no conflict of interest.
- 2.Matthay M, Ware L, Zimmerman G. The acute respiratory distress syndrome. J Clin Invest. 2012;122(2731):40.Google Scholar
- 4.Saguil A, Fargo M. Acute respiratory distress syndrome: diagnosis and management. Am Fam Physician. 2012;85(4):352–8.Google Scholar
- 6.Donahoe M. Acute respiratory distress syndrome: a clinical review. Pulmonary Circulation 2011; 1(2):192–211. doi: 10.4103/2045-8932.83454.
- 9.Cobelli C. Introduction to modeling in physiology and medicine. 1st ed ed. Academic Press series in biomedical engineering. Amsterdam: Academic Press; 2008.Google Scholar
- 15.Laufer B, Kretschmer J, Docherty PD, Chiew YS, Möller K. The influence of airway resistance in the dynamic elastance model. In: Kyriacou E, Christofides S, Pattichis CS, editors. XIV Mediterranean conference on medical and biological engineering and Computing 2016: MEDICON 2016, March 31st–April 2nd 2016, Paphos: Springer International Publishing; 2016. p. 56–61.Google Scholar
- 16.Knörzer A, Docherty PD, Chiew YS, Chase JG, Möller K. An Extension to the First Order Model of Pulmonary Mechanics to Capure a Pressure dependent Elastance in the Human Lung. Conference paper to 19th IFAC World Congress. 2014.Google Scholar
- 17.Laufer B, Docherty PD, Chiew YS, Moeller K, Chase JG, editors. Identifying pressure dependent elastance in lung mechanics with reduced influence of unmodelled effects. BMS 2015; 2015; Berlin.Google Scholar
- 18.Laufer B, Docherty PD, Knörzer A, Chiew YS, Langdon R, Möller K et al. Performance of variations of the dynamic elastance model in lung mechanics. Control Engineering Practice 2017, vol. 58, pp. 262–7.Google Scholar
- 19.Zilles K, Tillmann B. Anatomie. Springer; 2010.Google Scholar
- 22.Kramme R. Medizintechnik : Verfahren – Systeme – Informationsverarbeitung. 4., vollständig überarbeitete und erweiterte Auflage ed. SpringerLink: Bücher. Berlin, Heidelberg: Springer Berlin Heidelberg; 2011. doi: 10.1007/978-3-642-16187-2.
- 26.Stahl CA, Moller K, Schumann S, Kuhlen R, Sydow M, Putensen C, et al. Dynamic versus static respiratory mechanics in acute lung injury and acute respiratory distress syndrome. Crit Care Med. 2006;34(2090):8.Google Scholar