Title
A novel porcine model of ventilator-associated pneumonia caused by oropharyngeal challenge with pseudomonas aeruginosa
Date Issued
01 January 2014
Access level
open access
Resource Type
journal article
Author(s)
Li Bassi G.
Rigol M.
Marti J.D.
Saucedo L.
Ranzani O.T.
Roca I.
Cabanas M.
Muñoz L.
Giunta V.
Rinaudo M.
Esperatti M.
Fernandez-Barat L.
Ferrer M.
Vila J.
Ramirez J.
Torres A.
Department of Pulmonary and Critical Care Medicine
Publisher(s)
Lippincott Williams and Wilkins
Abstract
BACKGROUND:: Animal models of ventilator-associated pneumonia (VAP) in primates, sheep, and pigs differ in the underlying pulmonary injury, etiology, bacterial inoculation methods, and time to onset. The most common ovine and porcine models do not reproduce the primary pathogenic mechanism of the disease, through the aspiration of oropharyngeal pathogens, or the most prevalent human etiology. Herein the authors characterize a novel porcine model of VAP due to aspiration of oropharyngeal secretions colonized by Pseudomonas aeruginosa. METHODS:: Ten healthy pigs were intubated, positioned in anti-Trendelenburg, and mechanically ventilated for 72 h. Three animals did not receive bacterial challenge, whereas in seven animals, a P. aeruginosa suspension was instilled into the oropharynx. Tracheal aspirates were cultured and respiratory mechanics were recorded. On autopsy, lobar samples were obtained to corroborate VAP through microbiological and histological studies. RESULTS:: In animals not challenged, diverse bacterial colonization of the airways was found and monolobar VAP rarely developed. In animals with P. aeruginosa challenge, colonization of tracheal secretion increased up to 6.39 ± 0.34 log colony-forming unit (cfu)/ml (P < 0.001). VAP was confirmed in six of seven pigs, in 78% of the cases developed in the dependent lung segments (right medium and lower lobes, P = 0.032). The static respiratory system elastance worsened to 41.5 ± 5.8 cm H2O/l (P = 0.001). CONCLUSIONS:: The authors devised a VAP model caused by aspiration of oropharyngeal P. aeruginosa, a frequent causative pathogen of human VAP. The model also overcomes the practical and legislative limitations associated with the use of primates. The authors' model could be employed to study pathophysiologic mechanisms, as well as novel diagnostic/preventive strategies. © 2014 American Society of Anesthesiologists, Inc.
Start page
1205
End page
1215
Volume
120
Issue
5
Language
English
OCDE Knowledge area
Ciencia veterinaria
Scopus EID
2-s2.0-84899484557
PubMed ID
Source
Anesthesiology
ISSN of the container
00033022
Sources of information:
Directorio de Producción Científica
Scopus