Physicians try new weapons in the battle against superbugs

Antibiotic-resistant infections in surgical patients are escalating, but physicians say they can be prevented by rotating treatment, practicing intensive surveillance and isolating those infected.

By Victoria Stagg Elliott, amednews staff. Nov. 13, 2000.

Lena Napolitano, MD, chief of the surgical intensive care unit at the Baltimore Veterans Affairs Medical Center is a bit embarrassed.

"We had a significant increase in our surgical site infection rate in 1999," she explained, while participating in a panel discussion at the American College of Surgeons annual clinical congress last month. "This was very concerning to us."

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A number of patients infected with a drug-resistant bacteria had been in the cardiac intensive care unit at the same time. Additionally, one health care worker from that unit was found to be colonized. Although the employee's bug was identified as a different organism than the one that had infected some of the patients, the employee was not allowed to return to work until the bacteria had been eliminated.

This step was only the beginning.

Operating procedures changed to control the outbreak. Pre-op patients had to shower twice. The skin prep solution was altered. Shaving was done only outside the operating room. An intensive surveillance was launched. Patients scheduled for elective procedures who were found to have evidence of a resistant organism were not allowed to proceed with their surgery until the bug was cleared.

The good news, according to Dr. Napolitano, was that the methods worked and the outbreak was controlled. But, her institution is far from alone in struggling to find ways to prevent the increasing spread of drug-resistant infections among patients.

The implications for physicians, hospitals and the health care system cannot be underestimated.

"The CDC estimates that infection with antimicrobial-resistant organisms costs somewhere in the neighborhood of $4 billion per year," said panel member Robert Sawyer, MD, a transplant surgery specialist with the University of Virginia health system.

Patients infected with resistant organisms require more expensive antibiotics. They have longer and more expensive hospital stays. They spend more time in ICU, and they are more likely to die, said the panelists.

"Resistant gram-positive coccus certainly keep you in the hospital longer," said Dr. Sawyer. "Resistant enterococci can kill you. Being colonized with these organisms is bad because you tend to get an infection, and [for] a transplant patient it is even worse."

Dr. Sawyer's hospital experimented with quarterly rotations of their antibiotics for nosocomial infections in the ICU to try to eliminate the lag between the development of resistance and the change in regimen. They found the rotation decreased the actual number of infections, reduced resistance and lowered mortality.

Pamela Lipsett, MD, co-director of the ICU at Johns Hopkins Hospital in Baltimore, experimented with twice-weekly surveillance of ICU patients for resistant infections. Infected and colonized patients were isolated. Both practices were found to be effective at reducing mortality and costs.

"The cost of a single [vancomycin-resistant enterococci] culture is $22.50 and that includes swabs, the culture media and the nursing time," she said. "Our patients had a median of three cultures. [One] VRE infection adds $22,000 to ICU cost so you only have to identify and prevent six infections for this to be a very cost-effective strategy."

She said VRE rates can also be reduced by educating staff about the issue and paying greater attention to hand washing.

"Paying attention to these things -- which really, really don't cost any money at all -- can make a very big difference," she said. "Infection with resistant species related to a prolonged hospitalization is in fact a substantial and important risk factor. The degree of illness, antibiotic exposure and colonization with the species are also important."

Panelists said the emergence of resistant bacteria is probably caused by a number of factors, especially the high incidence of antibiotic use for surgical patients.

Dr. Sawyer stressed he wasn't advocating an end to antibiotic use, just more restraint.