Stress and strain within the lung

Purpose of reviewTo describe the physiological meaning and the clinical application of the lung stress and strain concepts. Recent findingsThe end-inspiratory plateau pressure and ratio of tidal volume/ideal body weight are inadequate surrogates for the end-inspiratory stress (equal to the transpulmonary pressure) and the end-inspiratory strain (change in lung volume relative to the resting volume). For a given plateau pressure or tidal volume/ideal body weight, stress and strain may vary largely due to the variability of chest wall elastance and the resting lung volume. The injurious limits of stress and strain in healthy lungs are reached when stress and strain reach the total lung capacity. This occurs when the resting lung volume (the baby lung in case of acute respiratory distress syndrome) is increased by two-fold to three-fold. As these limits are rarely reached in clinical practice and damage has been reported with stress and strain well below this upper limit, this implies the presence in the lung parenchyma of regions which act as stress raisers or pressure multipliers. These are primarily linked to the inhomogeneous distribution of local stress and strain. SummaryEnd-inspiratory stress and strain, as well as the lung inhomogeneity and the stress raisers, must be taken in account when setting mechanical ventilation.

[1]  Christopher M Waters,et al.  What do we know about mechanical strain in lung alveoli? , 2011, American journal of physiology. Lung cellular and molecular physiology.

[2]  C. Guérin The preventive role of higher PEEP in treating severely hypoxemic ARDS. , 2011, Minerva anestesiologica.

[3]  H. Baumann,et al.  Interventional lung assist enables lung protective mechanical ventilation in acute respiratory distress syndrome. , 2011, Minerva anestesiologica.

[4]  M. Antonelli,et al.  The Italian ECMO network experience during the 2009 influenza A(H1N1) pandemic: preparation for severe respiratory emergency outbreaks , 2011, Intensive Care Medicine.

[5]  M. Bailey,et al.  A randomised controlled trial of an open lung strategy with staircase recruitment, titrated PEEP and targeted low airway pressures in patients with acute respiratory distress syndrome , 2011, Critical care.

[6]  M. Plataki,et al.  Should mechanical ventilation be guided by esophageal pressure measurements? , 2011, Current opinion in critical care.

[7]  W. A. Wall,et al.  Local Strain Distribution in Real Three-Dimensional Alveolar Geometries , 2011, Annals of Biomedical Engineering.

[8]  Alessandro Santini,et al.  Lung stress and strain during mechanical ventilation: any safe threshold? , 2011, American journal of respiratory and critical care medicine.

[9]  Gaetano Perchiazzi,et al.  Lung regional stress and strain as a function of posture and ventilatory mode. , 2011, Journal of applied physiology.

[10]  V. Ranieri,et al.  When pressure does not mean volume? Body mass index may account for the dissociation , 2011, Critical Care.

[11]  L. Gattinoni,et al.  A validation study of a new nasogastric polyfunctional catheter , 2011, Intensive Care Medicine.

[12]  R. Hubmayr,et al.  Sizing the lung of mechanically ventilated patients , 2011, Critical care.

[13]  Christopher E. Hann,et al.  Dynamic functional residual capacity can be estimated using a stress-strain approach , 2011, Comput. Methods Programs Biomed..

[14]  R. Abbate,et al.  Ventilatory and ECMO treatment of H1N1-induced severe respiratory failure: results of an Italian referral ECMO center , 2011, BMC pulmonary medicine.

[15]  Gary E. Christensen,et al.  Analysis of Regional Mechanics in Canine Lung Injury Using Forced Oscillations and 3D Image Registration , 2010, Annals of Biomedical Engineering.

[16]  A. Majumdar,et al.  Mechanical forces regulate elastase activity and binding site availability in lung elastin. , 2010, Biophysical journal.

[17]  P. Pelosi,et al.  Recruitment maneuver in experimental acute lung injury: The role of alveolar collapse and edema , 2010, Critical care medicine.

[18]  Eleonora Carlesso,et al.  Ventilator-induced lung injury: The anatomical and physiological framework , 2010, Critical care medicine.

[19]  C. Guérin,et al.  Prone positioning improves survival in severe ARDS: a pathophysiologic review and individual patient meta-analysis. , 2010, Minerva anestesiologica.

[20]  S. Russo,et al.  Lung opening and closing during ventilation of acute respiratory distress syndrome. , 2010, American journal of respiratory and critical care medicine.

[21]  Matthias Briel,et al.  Higher vs lower positive end-expiratory pressure in patients with acute lung injury and acute respiratory distress syndrome: systematic review and meta-analysis. , 2010, JAMA.

[22]  R. Hubmayr Is there a place for esophageal manometry in the care of patients with injured lungs? , 2010, Journal of applied physiology.

[23]  V. Novack,et al.  Esophageal pressures in acute lung injury: do they represent artifact or useful information about transpulmonary pressure, chest wall mechanics, and lung stress? , 2010, Journal of applied physiology.

[24]  Henry E Fessler,et al.  Are esophageal pressure measurements important in clinical decision-making in mechanically ventilated patients? , 2010, Respiratory care.

[25]  P. Pelosi,et al.  Prone position prevents regional alveolar hyperinflation and mechanical stress and strain in mild experimental acute lung injury , 2009, Respiratory Physiology & Neurobiology.

[26]  M. Wysocki,et al.  Is there an optimal breath pattern to minimize stress and strain during mechanical ventilation? , 2009, Intensive Care Medicine.

[27]  Atul Malhotra,et al.  Mechanical ventilation guided by esophageal pressure in acute lung injury. , 2008, The New England journal of medicine.

[28]  Massimo Cressoni,et al.  Lung stress and strain during mechanical ventilation for acute respiratory distress syndrome. , 2008, American journal of respiratory and critical care medicine.

[29]  Arthur S Slutsky,et al.  Lung stress and strain in acute respiratory distress syndrome: good ideas for clinical management? , 2008, American journal of respiratory and critical care medicine.

[30]  P. Pelosi,et al.  Extracellular matrix and mechanical ventilation in healthy lungs: back to baro/volotrauma? , 2008, Current opinion in critical care.

[31]  F. Jardin Tidal volume reduction in patients with acute lung injury when plateau pressures are not high. , 2006, American journal of respiratory and critical care medicine.

[32]  L. O’Neill TLRs play good cop, bad cop in the lung , 2005, Nature Medicine.

[33]  Luciano Gattinoni,et al.  The concept of “baby lung” , 2005, Intensive Care Medicine.

[34]  C. Roussos,et al.  Prone position reduces lung stress and strain in severe acute respiratory distress syndrome , 2005, European Respiratory Journal.

[35]  B. Lachmann,et al.  Open up the lung and keep the lung open , 1992, Intensive Care Medicine.

[36]  M. Toshima,et al.  Three-dimensional architecture of elastin and collagen fiber networks in the human and rat lung. , 2004, Archives of histology and cytology.

[37]  D. Chiumello,et al.  Physical and biological triggers of ventilator-induced lung injury and its prevention , 2003, European Respiratory Journal.

[38]  P. Pelosi,et al.  Vertical gradient of regional lung inflation in adult respiratory distress syndrome. , 1994, American journal of respiratory and critical care medicine.

[39]  A. Al-Jurf Positive end-expiratory pressure. , 1981, Surgery, gynecology & obstetrics.

[40]  J. Mead,et al.  Stress distribution in lungs: a model of pulmonary elasticity. , 1970, Journal of applied physiology.

[41]  Charles F. Code,et al.  Handbook of Physiology; a Critical, Comprehensive Presentation of Physiological Knowledge and Concepts , 2011 .