A clinical study led by UNMC showed that antiseptic-coated central venous catheters (CVCs) resulted in significantly lower rates of bacterial colonization on the catheters and fewer patients developing bacteremia (bacteria invading the blood stream).
Mark Rupp, M.D., associate professor in the UNMC department of internal medicine, led the clinical trial at Nebraska Health System, UNMC’s health partner. Nine other centers took part, including such prominent institutions as Johns Hopkins Hospital, the University of Pittsburgh, and Brigham and Women’s Hospital, among others.
“Although hospital-acquired infections are not something most people fear, and there are not groups of victims or victims’ families pushing for additional research and preventative efforts, they are a major problem in U.S. hospitals and result in a significant amount of morbidity and mortality,” Dr. Rupp said.
Annually in the United States, about 200,000 people experience bacteremia due to infected IV catheters. This leads to at least 6,000 deaths, more than 2 million extra days of hospitalization and more than $1.2 billion of excess cost. In the typical adult intensive care unit in the United States, a little more than half of the patients will have a CVC in place on any given day.
In this clinical trial, catheters coated with the antiseptics chlorhexidine and silver sulfadiazine were compared to non-coated catheters. The coated catheters decreased the rate of bacteremia three-fold, from 1.2 cases per 1,000 catheter days to 0.4 per 1,000 catheter days. The rate of bacterial colonization also decreased, from 23 per 1,000 days of catheter use to 9.8 per 1,000 days of catheter use. Bacterial colonization — defined by finding bacteria on the catheters at the time of removal — is thought to be the first step in the pathogenesis of CVC-associated infections. Therefore, if the coated catheters can prevent colonization, it is felt they most likely will prevent the more serious problem of bacteremia.
Dr. Rupp presented the study results at the Interscience Conference on Antimicrobial Agents and Chemotherapy, which took place in December in Chicago.
In addition to leading this clinical trial, Dr. Rupp also is doing laboratory research on the properties that allow the bacteria to “stick” to the catheters.
Dr. Rupp and Paul Fey, Ph.D., assistant professor in the UNMC department of internal medicine, working with a number of international collaborators, have defined specific bacterial adhesins and the genes that encode them.
“We hope that with the greater understanding of the pathogenesis of these infections will come novel means to prevent and treat them,” Dr. Rupp said. “Perhaps in the future a vaccine, directed against one of the adhesins, can be given to patients with prosthetic medical devices, such as catheters, heart valves and artificial joints, in order to prevent these horrendous infections.”
Dr. Fey is defining how the microbes turn their adhesins on and off. Said Dr. Rupp, “Perhaps we can figure out a way to down-regulate or switch off the production of the adhesins. This may result in a novel means to treat these infections.”
More study will be needed to determine if the antiseptic-coated catheters will become standard procedure in hospitals. Studies need to be performed that demonstrate their cost-effectiveness and define which groups of patients are most likely to benefit from the coated catheters. In addition, comparative studies between the chlorhexidine/silver sulfadiazine-coated catheters and other coated catheters should be performed to define which is most effective, Dr. Rupp said.
“The new antiseptic-coated venous catheters show real promise for prevention of infection,” Dr. Rupp said. “We were very pleased to lead this trial, and we hope the new catheters result in saved lives.”
Photos in descending order: Mark Rupp, Paul Fey.