Oropharyngeal Colonization

  • The oropharyngeal colonizing flora is often the source of the causative organisms of VAP.([FOOTNOTE=Garrouste-Orgeas M, Chevret S, Arlet G, et al. Oropharyngeal or gastric colonization and nosocomial pneumonia in adult intensive care unit patients. A prospective study based on genomic DNA analysis. Am J Respir Crit Care Med. 1997;156(5):1647-1655. [ View Abstract ]],[ANCHOR=],[LINK=])
  • Interventions that reduce oropharyngeal colonization reduce the incidence of VAP.([FOOTNOTE=Chlebicki MP, Safdar N. Topical chlorhexidine for prevention of ventilator-associated pneumonia: a meta-analysis. Crit Care Med. 2007;35(2):595-602. [ View Abstract ]],[ANCHOR=],[LINK=])
  • The sequence of colonization in patients undergoing mechanical ventilation is the oropharynx (36 h), the stomach (36-60 h), the lower respiratory tract (60-84 h) and thereafter the endotracheal tube (60-96 h)([FOOTNOTE=Feldman C, Kassel M, Cantrell J, et al. The presence and sequence of endotracheal tube colonization in patients undergoing mechanical ventilation. Eur Respir J. 1999;13(3):546-551. [ View Abstract ]],[ANCHOR=],[LINK=])
  • While microaspiration of contaminated secretion is the primary pathway for VAP, biofilm on the endotracheal tube may play a role in maintaining the infection.([FOOTNOTE=Deem S, Treggiari MM. New endotracheal tubes designed to prevent ventilator-associated pneumonia: do they make a difference? Respir Care. 2010;55(8):1046-1055. [ View Abstract ]],[ANCHOR=],[LINK=])

Microaspiration

 

  • The major source of infection may be contaminated oropharyngeal secretions that leak through folds of the inflated ETT cuff.([FOOTNOTE=Cardenosa Cendrero JA, Sole-Violan J, Bordes Benitez A, et al. Role of different routes of tracheal colonization in the development of pneumonia in patients receiving mechanical ventilation. Chest. 1999;116(2):462-470. [ View Abstract ]],[ANCHOR=],[LINK=]),([FOOTNOTE=Blunt MC, Young PJ, Patil A, Haddock A. Gel lubrication of the tracheal tube cuff reduces pulmonary aspiration. Anesthesiology. 2001;95(2):377-381. [ View Abstract ]],[ANCHOR=],[LINK=])
  • Microaspiration occurs in virtually 100 percent of inflated high-volume, low-pressure ETT cuffs.6
  • Microaspiration is reduced but still present in the semirecumbent position compared to the supine position.([FOOTNOTE=Orozco-Levi M, Torres A, Ferrer M, et al. Semirecumbent position protects from pulmonary aspiration but not completely from gastroesophageal reflux in mechanically ventilated patients. Am J Respir Crit Care Med. 1995;152(4 Pt 1):1387-1390. [ View Abstract ]],[ANCHOR=],[LINK=])
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