ARDS Decreases Pulmonary Artery Compliance in a Porcine Model
2016 (English)Conference paper (Refereed)
Rationale: Importance of pulmonary hemodynamic disarrangements in ARDS has been remarked recently. In this study we describe the effect of ARDS on pulmonary artery compliance and the related effect on pulmonary hemodynamics. In this way we highlight the importance of pulsatile hemodynamic evaluation beyond the classic evaluation based only on resistance.
Methods: 17 anesthetized and muscle relaxed pigs were monitored with a transonic flow probe and high fidelity micro-tip pressure sensor placed in the pulmonary artery through a small thoracotomy. An experimental model of ARDS was induced in these animals by means of lung saline lavages followed by two hours of injurious mechanical ventilation. Pulmonary artery compliance was measured as the stroke volume divided by the pulse pressure. Waveform analysis of pulmonary artery pressure and flow signal was applied to calculate the following variables: first harmonic impedance magnitude (inversely related with arterial compliance), characteristic impedance, wave reflections (which are affected by arterial compliance) magnitude and peak and foot arrival time (normalized to cardiac period). These variables are related to the pulmonary vessels efficiency to transmit pressure and flow produced by the right ventricle. In addition, pulmonary vascular resistance was evaluated as usual. Variables were evaluated before (Baseline) and after (ARDS) development of the model.
Results: Comparing with Baseline, ARDS provoked a decrease in pulmonary artery compliance (3.03±0.99 vs 1.53±0.41 ml/mmHg, p<0.001), and in the wave reflections arrival time of foot (0.18±0.09 vs 0.11±0.05, p<0.001) and peak (0.50±0.12 vs 0.39±0.10, p< 0.001) and an increase in the impedance magnitude of the first harmonic (80±29 vs 145±38 dyn.s.cm-5, p<0.001) and in the pulmonary vascular resistance (230±79 vs 504±129 dyn.s.cm-5, p<0.001). Characteristic impedance and wave reflections magnitude showed no differences.
Conclusions: In this porcine model, ARDS provoked a decrease in pulmonary artery compliance. This effect was followed by a deterioration of pulmonary vascular efficiency. Our findings can be relevant for the pathophysiology of right ventricle failure during ARDS. This abstract is funded by: European Society of Intensive Care Medicine (ESICM), Basic Science Award 2012, the Swedish Heart and Lung foundation and the Swedish Research Council (K2015-99X-22731-01-4)
Place, publisher, year, edition, pages
, Am J Respir Crit Care Med
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-308413OAI: oai:DiVA.org:uu-308413DiVA: diva2:1049702
International Conference of the American-Thoracic-Society (ATS)
Am J Respir Crit Care Med 193;2016:A7917
Internet address: www.atsjournals.org Online Abstracts Issue2016-11-252016-11-252016-11-25