Abstract
Negative pressure ventilation via an external device (‘iron lung’) has the potential to provide better oxygenation with reduced barotrauma in patients with ARDS. This study was designed to see if oxygenation differences between positive and negative ventilation could be explained by CT. Six anaesthetized rabbits had ARDS induced by repeated saline lavage. Rabbits were ventilated with positive pressure ventilation (PPV) and negative pressure ventilation (NPV) in turn. Dynamic CT images were acquired over the respiratory cycle. A computer-aided method was used to segment the lung and calculate the range of CT densities within each slice. Volumes of ventilated lung and atelectatic lung were measured over the respiratory cycle. NPV was associated with an increased percentage of ventilated lung and decreased percentage of atelectatic lung. The most significant differences in ventilation and atelectasis were seen at mid-inspiration and mid-expiration (ventilated lung NPV = 61%, ventilated lung PPV = 47%, p < 0.001; atelectatic lung NPV = 10%, atelectatic lung PPV 19%, p < 0.001). Aeration differences were not significant at end-inspiration. Dynamic CT can show differences in lung aeration between positive and negative ventilation in ARDS. These differences would not be appreciated if only static breath-hold CT was used.
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Bernard GR, Artigas A, Brigham KL et al (1994) The American-European consensus conference on ARDS. Definitions, mechanisms, relevant outcomes, and trial co-ordination. Am J Respir Crit Care Med 149:818–824
Thomsen GE, Morris AH (1995) Incidence of the adult respiratory distress syndrome in the State of Utah. Am J Respir Crit Care Med 152:965–971
Hudson LD, Steinberg KP (1999) Epidemiology of acute lung injury and ARDS. Chest 116:74S–82S
Dos Santos CC, Slutsky AS (2005) Ventilation therapies and strategies. In: Finkelstein J, Notter R, Holm B (eds) Lung injury: mechanisms, pathophysiology, and therapy. Taylor and Francis, New York
Grasso F, Engelberts D, Helm E et al (2008) Negative-pressure ventilation: better oxygenation and less lung injury. Am J Respir Crit Care Med 177:412–418
Maunder RJ, Schuman WP, McHugh JW et al (1986) Preservation of normal lung regions in the adult respiratory distress syndrome. Analysis by computed tomography. JAMA 255:2463–2465
Pelosi P, Brazzi L, Gattinoni L (2002) Prone position in acute respiratory distress syndrome. Eur Respir J 20:1017–1028
Henzler D, Pelosi P, Dembinski R et al (2005) Respiratory compliance but not gas exchange correlates with changes in lung aeration after a recruitment maneuver: an experimental study in pigs with saline lavage lung injury. Critical Care 9:R471–R482
Luecke T, Herrmann P, Kraincuk P, Pelosi P (2005) Computed tomography scan assessment of lung volume and recruitment during high-frequency oscillatory ventilation. Crit Care Med 33(3 Suppl):S155–S162
Matthias D, Karmrodt J, Bletz C et al (2005) Analysis of atelectasis, ventilated and hyperinflated lung during mechanical ventilation by dynamic CT. Chest 128:3757–3770
Markstaller K, Kauczor HU, Weiler N, Karmrodt J, Doebrich M, Ferrante M, Thelen M, Eberle B (2003) Lung density distribution in dynamic CT correlates with oxygenation in ventilated pigs with lavage ARDS. Br J Anaesth 91:699–708
Neumann P, Berglund JE, Fernandez Mondejar E et al (1998) Dynamics of lung collapse and recruitment during prolonged breathing in porcine lung injury. J Appl Physiol 85:1533–1543
Markstaller K, Eberle B, Kauczor HU et al (2001) Temporal dynamics of lung aeration determined by dynamic CT in a porcine model of ARDS. Br J Anaes 87:459–468
Talakoub O, Helm E, Alirezaie J, Babyn, P, Kavanagh B, Grasso F, Engelberts D (2007) An automatic wavelet-based approach for lung segmentation and density analysis in dynamic CT. Computational intelligence in image and signal processing, 1–5 April 2007, pp 369–374. doi:10.1109/CIISP.2007.369197
Gattinoni L, Caironi P, Pelosi P, Goodman L (2001) What has computed tomography taught us about the acute respiratory distress syndrome? Am J Respir Crit Care Med 164:1701–1711
Lu Q, Malbouisson LM, Mourgeon E et al (2001) Assessment of PEEP-induced reopening of collapsed lung regions in acute lung injury: are one or three CT-sections representative of the entire lung? Intensive Care Med 27:1504–1510
Bletz C, Markstaller K, Karmrodt J et al (2004) Quantification of atelectases in artificial respiration: spiral versus dynamic single-slice CT. Fortschr Rontgenstr 176:409–416
Vieira SRR, Nieszkowska A, Lu Q et al (2005) Low spatial resolution computed tomography underestimates lung over-inflation resulting from positive pressure ventilation. Crit Care Med 33:741–749
Heussel CP, Hafner B, Thelen M, Kauczor H-U (2000) Computed tomography of the trachea: paired inspiratory/expiratory spiral-CT and cine-CT during respiration. Eur Radiol 10:273
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Helm, E., Talakoub, O., Grasso, F. et al. Use of dynamic CT in acute respiratory distress syndrome (ARDS) with comparison of positive and negative pressure ventilation. Eur Radiol 19, 50–57 (2009). https://doi.org/10.1007/s00330-008-1105-8
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DOI: https://doi.org/10.1007/s00330-008-1105-8