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The evolution of drug-resistant microorganisms in patients with prolonged mechanical ventilation

Jung-Yien Chien1, Po-Ren Hsueh, Chong-Jen Yu

  • 1Department of Internal Medicine, National Taiwan University Hospital, Yun-Lin Branch, Douliu, Taiwan.

American Journal of Infection Control
|November 7, 2008
PubMed
Abstract

Insights

Prolonged mechanical ventilation (PMV) patients often harbor antimicrobial resistance. Infections with multidrug-resistant organisms in these patients are common and linked to increased mortality.

Area of Science:

  • Infectious Diseases
  • Critical Care Medicine
  • Microbiology

Background:

  • Patients on prolonged mechanical ventilation (PMV) are susceptible to developing antimicrobial resistance.
  • Respiratory tracts of PMV patients can act as reservoirs for resistant microorganisms.

Purpose of the Study:

  • To assess antimicrobial-resistant microorganisms in the respiratory tracts of patients receiving PMV.
  • To investigate the correlation between antimicrobial use and resistance development.
  • To determine the association between multidrug-resistant infections and mortality in PMV patients.

Main Methods:

  • Analysis of microorganisms from tracheal aspirates of PMV patients with lower airway infections over a 6-month period.
  • Utilized univariate and multivariate logistic regression models to identify risk factors and outcomes.

Main Results:

  • Antimicrobial resistance in Pseudomonas aeruginosa and Klebsiella pneumoniae peaked between weeks 4-15 of PMV.
  • Methicillin-resistant Staphylococcus aureus (MRSA) emerged rapidly within the first 3 weeks.
  • Acquisition of multidrug-resistant P. aeruginosa and MRSA correlated with prior ceftazidime exposure.
  • Multidrug-resistant Acinetobacter baumannii emergence correlated with piperacillin/tazobactam and imipenem exposure.
  • Lower respiratory tract infections with multidrug-resistant microorganisms were independently associated with increased 6-month mortality.

Conclusions:

  • Lower respiratory tract infections with multidrug-resistant microorganisms are prevalent in patients receiving PMV.
  • These infections are significantly associated with higher 6-month mortality rates.

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