MONDAY, May 19 (HealthDay News) -- Endotracheal tubes coated with silver dramatically reduce infections from highly resistant bacteria, researchers report.

Patients on ventilators breathe through a tube placed through their trachea and into the lung, and they are at risk for developing what is called ventilator-associated pneumonia.

"Ventilator-associated pneumonia can be caused by a variety of pathogens," said lead researcher Dr. Andrew Shorr, from the Washington Hospital Center in Washington, D.C. "We are clearly worried about some pathogens more than others, such as MRSA."

Endotracheal tubes that have no coating can be infected with highly resistant bacteria, including methicillin-resistant Staphylococcus aureus( MRSA), Pseudomonas aeruginosa and Acinetobacter bumanii, and these infections can be passed to the patient.

Ventilator-associated pneumonia can be a serious and sometimes deadly condition, particularly if the infection is caused by pathogens that are resistant to antibiotics.

Shorr noted that the silver-coated endotracheal tubes are very effective in preventing infections from highly resistant bacteria. "This has huge implications, because highly resistant bacteria are most likely the ones associated with a higher risk of death from ventilator-associated pneumonia," he said.

These infections are also associated with higher costs for treatment, Shorr said. The average costs of treating ventilator-associated pneumonia can be more than $40,000, because of the length of stay in the intensive care unit, he noted.

The report was presented Monday at the American Thoracic Society's 2008 International Conference in Toronto.

In the study, Shorr's group assigned 1,509 patients to receive traditional, uncoated endotracheal tubes or silver-coated ones. They found that using the silver-coated tube reduced ventilator-associated pneumonia by 40 percent.

In addition, highly resistant infections were less than half as likely to occur among those patients who received the silver-coated tubes, Shorr's team reported.

"People need to focus more on ventilator-associated pneumonia," Shorr said. "We now have a tool for preventing ventilator-associated pneumonia, which is effective in preventing infections from highly resistant bacteria."

One expert thinks that silver coatings are an effective way to cut down on many antibiotic-resistant infections.

"The silver coating doesn't prevent all infections, but it cuts down on infections significantly -- and that's important," said Dr. Philip Tierno, director of clinical microbiology and immunology at New York University Medical Center.

Many of these infections are very resistant to antibiotics, making them difficult to treat, Tierno said. "Even if you cut down 40 percent of the incidents of all ventilator-associated pneumonias, that is lifesaving," he said.

Reducing the incidence of ventilator-associated pneumonia is also cost-effective, Tierno said. "It's a costly endeavor having to maintain the patient for a longer period of time in the hospital, wasting money and resources on fighting and unnecessary infection that might have been prevented," he said.

Tierno noted that silver has its limitations because some organisms have a tolerance to silver. Silver and other coatings are being tried on other products such as catheters to cut down on infections, he said.

"All these products will cut down on expenses, because if you can prevent something that's always better than treating something-- an ounce of prevention is worth a pound of cure, like my grandmother said," Tierno said.

More information

For more on ventilator-assisted pneumonia, visit the U.S. National Library of Medicine.