Needle-less intravascular catheter connector valve could lead to patient infections

Patients might be at greater risk for developing bloodstream infections due to a common device used in hospitals around the country, according to a research team at the University of Nebraska Medical Center (UNMC) in Omaha, Nebraska.

The device is a needle-less intravascular catheter connector valve, commonly used for hospital patients with a vascular catheter in place. Vascular catheters are widely used in many types of patients for the infusion of medications, blood products or fluids, and the connector valve is the small piece of equipment that connects the catheter to the IV tubing.

The first generation of needle-less devices was introduced into medical care over a decade ago in order to prevent needlestick injuries and bloodborne pathogen exposure in health care workers. More recently, mechanical valves have been incorporated into the devices in an attempt to minimize the risk of catheter occlusion. Unfortunately, some of these devices may be putting patients in harm's way, said Mark Rupp, M.D.

He said: “It really points out that even seemingly small changes in vascular access devices can have devastating unintended consequences, and how careful we need to be when people's lives are at stake.”

Rupp is an infectious diseases specialist at UNMC and The Nebraska Medical Center, and the principal investigator on the study. His team's findings were reported in the June 1 issue of Clinical Infectious Diseases , a leading scientific journal.

The particular needle-less connector valve in the study was introduced into clinical use in February 2005 at The Nebraska Medical Center, but later completely removed from clinical use when evidence associated the valve with an increased rate of bloodstream infection. Bloodstream infections are quite serious and can result in mortality or prolonged hospital stay.

The UNMC research team is one of the first groups in the country to note this
trend. They initially presented their findings to the scientific medical community in the spring of 2006.

In performing blood cultures on patients hospitalized during the study period, the researchers determined that ICU patients with the needle-less connector valve experienced bloodstream infections at nearly three times the rate compared to the time period before the valve was used. In regular inpatient nursing units, the bloodstream infection rate more than doubled when the needle-less connector valves were in use.

With the needle-less connector valves, bloodstream infections in ICU patients increased from 3.87 infections per 1,000 catheter days to 10.64 infections per 1,000. In inpatient nursing units, the introduction of the connector valves resulted in an increase of bloodstream infections from 3.47 infections per 1,000 catheter days to 7.3 infections per 1,000. Since discontinuing the use of needle-less connector valves, Dr. Rupp noted that the bloodstream infection rate at The Nebraska Medical Center has returned to the accepted national benchmark level.

“Every hospital in the country is using similar types of devices,” Dr Rupp said. “We felt it incumbent upon ourselves to report our study results in a scientific journal. In addition, we notified the Food and Drug Administration (FDA) and the manufacturer.”

Dr. Rupp said similar needle-less connector valves are produced by at least six different manufacturers. “Many of these devices are being introduced into the health care arena without undergoing rigorous testing in clinical settings,” he said. “Hospitals and doctors need to be aware of the increased risks potentially involved with using some of these devices.”

Dr. Rupp said the valves have a shallow depression and rim. “It's possible that microbes and debris could collect in this depression, making them relatively resistant to cleansing or disinfectants,” he said. “They also are opaque, making it more difficult for health care workers to observe if blood or infusion products are collecting within the valve.”

Once the higher rate of bloodstream infections was determined, Dr. Rupp said the hospital immediately stopped using the mechanical needle-less connector valves and went back to using the older version.