Silver-Coated Endotracheal Tubes May Reduce VAP

Among intensive care unit patients who required mechanical ventilation, use of a silver-coated endotracheal tube resulted in reduced incidence of pneumonia associated with ventilators, according to a report in the August 20 issue of JAMA (the Journal of the American Medical Association).

Ventilator-associated pneumonia (VAP) results in longer hospital stays, increased healthcare costs and infection rates. VAP is likely to develop when pathogenic bacteria colonize the aerodigestive tract or when patients exhale contaminated secretions.

Silver has displayed antimicrobial activity in the laboratory and has blocked the formation of harmful pathogens on ventilator tubes in animal models. Marin Kollef, MD, of the Washington University School of Medicine, and colleagues in the NASCENT Investigation Group reported on a randomized controlled trial involving patients at 54 centers expected to require mechanical ventilation for 24 hours or longer. Between 2002 and 2006, 2,003 patients were randomly assigned to undergo intubation with either a silver-coated tube or a similar tube that was not coated.

Of 1,509 patients who were intubated for 24 hours or longer, 4.8 percent of those with silver-coated tubes developed ventilator-associated pneumonia, compared with 7.5 percent of those with uncoated tubes — a 35.9 percent relative reduction in risk. Among 1,932 patients who were on ventilators for any length of time, the silver coating was associated with a 34.2 percent relative reduction in risk of developing pneumonia (3.8 percent of those with silver-coated tubes versus 5.8 percent with uncoated tubes).

In addition, the silver-coated tubes were associated with a delayed occurrence of ventilator-associated pneumonia. No differences were seen between the two groups in median (midpoint) duration of intubation, length of stay in the intensive care unit (ICU) or in the hospital, death rates or frequency and severity of adverse events.

The results of this multicenter study demonstrate that the silver-coated endotracheal tube significantly reduced the incidence of microbiologically confirmed ventilator-associated pneumonia and had its greatest benefit during the peak time of ventilator-associated pneumonia occurrence, without any notable adverse events, the authors concluded.

 “The silver-coated endotracheal tube appears to offer a unique approach because it is the first intervention that becomes user-dependent after intubation, requiring no further action by the clinician,” the wrote.

The study was supported by a research grant from C. R. Bard Inc.

Source: The American Medical Association