Preventive Strategies in VAP: Focus on Silver-Coated Endotracheal Tubes



Introduction: Ventilator-associated pneumonia (VAP) is problematic because of its frequency, morbidity, and mortality. Many strategies have been studied in an attempt to reduce the rate of VAP. This chapter provides a comprehensive review of silver-coated endotracheal tubes in the prevention of VAP.

Methods: Two silver-coated endotracheal tubes have been studied in comparison with similar, uncoated tubes—each beginning with preclinical models and progressing to clinical studies. One is commercially available (Agento® IC, C. R. Bard, Covington, Georgia, United States) and is coated with silver ions micro-dispersed in a proprietary hydrophilic polymer. The other remains investigational and is prepared by submerging a standard endotracheal tube into silver sulfadiazine (with or without chlorhexidine) and polyurethane.

Results: Both silver-coated tubes were active in preclinical models designed to mimic surrogate endpoints for VAP, such as in vitro bacterial adherence, biofilm formation, and bacterial burden in animal models. Both tubes were active in phase 2 studies of patients requiring mechanical ventilation. The commercially available tube was active in a randomized, phase 3 study and reduced the incidence of microbiologically confirmed VAP at any time after intubation (silver vs. uncoated, 37/766 [4.8 %] vs. 56/743 [7.5 %]; P = 0.03; relative risk reduction, 35.9 %) and within 10 days of intubation (27/766 [3.5 %] vs. 50/743 [6.7 %]; P = 0.005, relative risk reduction, 47.6 %).

Conclusions: The silver-coated endotracheal tube is a promising strategy for preventing VAP. The commercially available tube meets the standards for evidence-based guidelines because effectiveness is supported by the results of a well-designed, phase 3 study. In addition, the device is suitable for use in the intensive care unit because it becomes user independent after intubation and does not add to the burden of busy healthcare providers.


Intensive Care Unit Endotracheal Tube Relative Risk Reduction Silver Coating Bacterial Burden 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


AMMI Canada

Association of Medical Microbiology and Infectious Disease Canada


American Thoracic Society/Infectious Diseases Society of America


British Society for Antimicrobial Chemotherapy


Canadian Critical Care Trials Group


Clinical pulmonary infection score


Good practice point


Healthcare-associated pneumonia


Intensive care unit


Institute for Healthcare Improvement


North American Silver-Coated Endotracheal Tube study


National Healthcare Safety Network


Society for Healthcare Epidemiology of America/IDSA


Specific, measurable, achievable, relevant, and time bound


Ventilator-associated pneumonia


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Washington University School of MedicineSt. LouisUSA

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