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Murine Oropharyngeal Aspiration Model of Ventilator-associated and Hospital-acquired Bacterial Pneumonia
04:32

Murine Oropharyngeal Aspiration Model of Ventilator-associated and Hospital-acquired Bacterial Pneumonia

Published on: June 28, 2018

Patterns of early and late ventilator-associated pneumonia due to methicillin-resistant Staphylococcus aureus in a

Jeffry L Kashuk1, Ernest E Moore, Connie S Price

  • 1Department of Surgery, Division of Acute Care Surgery, Penn State Hershey Medical Center and College of Medicine, Hershey, PA 17033, USA. jkashuk@hmc.psu.edu

The Journal of Trauma
|February 23, 2010
PubMed
Abstract

Insights

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is a concern, but early ventilator-associated pneumonia (VAP) in trauma patients is rare. Admission nasal swabs did not predict MRSA VAP risk in this study.

Area of Science:

  • Critical Care Medicine
  • Infectious Diseases
  • Trauma Surgery

Background:

  • Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is increasingly prevalent.
  • CA-MRSA is a potential cause of early ventilator-associated pneumonia (VAP) in trauma patients.
  • Understanding MRSA VAP incidence in ventilated trauma patients is crucial.

Purpose of the Study:

  • To determine the prevalence of early (≤4 days) and late (>4 days) MRSA VAP in ventilated trauma patients.
  • To correlate MRSA VAP findings with admission nasal swab results.
  • To evaluate the utility of nasal swabs for identifying MRSA VAP risk.

Main Methods:

  • Retrospective review of prospective trauma and infectious disease databases.
  • Analysis of patients with early (≤4 days) and late (>4 days) VAP over a 4-year period.
  • Pneumonia diagnosis via clinical pulmonary infection score, bronchoalveolar lavage, and quantitative cultures; routine admission nasal swabs for MRSA carrier identification.

Main Results:

  • 176 patients with S. aureus VAP identified; 4 (2.2%) had early MRSA VAP, 40 (23%) had late MRSA VAP.
  • None of the 4 patients with early MRSA VAP had positive admission nasal swabs.
  • Late MRSA VAP occurred in 40 patients (23%), while late methicillin-susceptible S. aureus (MSSA) VAP occurred in 85 patients (64%).

Conclusions:

  • A low incidence of early and late MRSA VAP was observed in ventilated trauma patients, despite national increases in MRSA.
  • Admission nasal swabs were ineffective in identifying patients at risk for MRSA VAP.
  • The efficacy of empiric vancomycin for early S. aureus VAP is questionable; nasal swabs are not helpful for risk stratification.

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