Journal article
Regional aeration and perfusion distribution in a sheep model of endotoxemic acute lung injury characterized by functional computed tomography imaging
Critical care medicine, Vol.37(8), pp.2402-2411
08/01/2009
DOI: 10.1097/CCM.0b013e3181a02354
PMID: 19531954
Abstract
Objectives. Sepsis-related lung injury is the most common and morbid form of acute lung injury. The objective of this study was to develop an ovine model of septic acute lung injury and characterize its pathophysiology regarding its recruitability and changes in regional aeration and perfusion distributions at injury and during injury evolution.
Design: Experimental animal study.
Setting: University hospital research laboratory.
Subjects: Adult sheep.
Interventions: Twenty-one anesthetized and mechanically ventilated sheep received intravenous Escherichia coli endotoxin infusion until severe hypoxemia was obtained. Inspiratory- and expiratory-gated computed tomography images of the entire lung were acquired in six subjects at baseline, during endotoxin infusion, and at injury. Perfusion images were obtained at apex and base locations at baseline and injury. Computed tomography images were analyzed for total, air, and tissue lung volumes and axial and vertical aeration and perfusion gradients. Lung recruitability was studied in a subgroup of subjects after injury.
Measurements and Main Results: Computed tomography imaging showed a patchy, progressive decrease in air volume as injury evolved, partially replaced by an increase in tissue volume. Perfusion showed a non dependent-to-dependent gradient at baseline that remained relatively unchanged with injury. Perfusion to poorly aerated lung regions was unchanged or increased after injury. Aeration and perfusion distributions at baseline were primarily dorsal or dependent. After injury, the heterogeneity of perfusion and aeration increased and the effect of gravity decreased. Recruitment maneuvers and changes in positive end-expiratory pressure resulted in no improvement in aeration or oxygenation.
Conclusions. The severe hypoxemia, moderate volume loss, and perfusion patterns are consistent with an injury model in which hypoxemia is exacerbated by endotoxin-mediated failure of hypoxic pulmonary vasoconstriction. (Crit Care Med 2009; 37: 2402-2411)
Details
- Title: Subtitle
- Regional aeration and perfusion distribution in a sheep model of endotoxemic acute lung injury characterized by functional computed tomography imaging
- Creators
- Ana Fernandez-Bustamante - Johns Hopkins UniversityR. Blaine Easley - Johns Hopkins Med Inst, Dept Anesthesiol & Crit Care Med, Baltimore, MD 21205 USAMatthew Fuld - University of IowaDaniel Mulreany - Johns Hopkins Med Inst, Dept Anesthesiol & Crit Care Med, Baltimore, MD 21205 USAEric A. Hoffman - Univ Iowa, Dept Radiol, Div Physiol Imaging, Iowa City, IA 52242 USABrett A. Simon - Johns Hopkins Med Inst, Dept Anesthesiol & Crit Care Med, Baltimore, MD 21205 USA
- Resource Type
- Journal article
- Publication Details
- Critical care medicine, Vol.37(8), pp.2402-2411
- Publisher
- Lippincott Williams & Wilkins
- DOI
- 10.1097/CCM.0b013e3181a02354
- PMID
- 19531954
- ISSN
- 0090-3493
- eISSN
- 1530-0293
- Number of pages
- 10
- Grant note
- R01HL064368 / NATIONAL HEART, LUNG, AND BLOOD INSTITUTE; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA; NIH National Heart Lung & Blood Institute (NHLBI) DAMD17-02-1-0732 / Department of Defense; United States Department of Defense EX2004-0283 / Spanish Ministry of Education; Spanish Government HL64368 / National Institutes of Health; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA
- Language
- English
- Date published
- 08/01/2009
- Academic Unit
- Roy J. Carver Department of Biomedical Engineering; Radiology; Internal Medicine
- Record Identifier
- 9984318815202771
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