IV Connectors Studied for Preventing Bacterial Growth

Two IV needleless connectors made by RyMed Technologies outperformed other connectors in suppressing bacteria known to cause catheter-related bloodstream infections (CRBSI), according to a poster presentation at the 2010 State of the Science Congress on Nursing Research.

The poster also summarized research showing that RyMed's InVision-Plus® reduced occlusions 20 percent to 84 percent in clinical settings with cancer patients. Occlusions have been shown by research to lead to CRBSI, the poster notes.

The biennial congress is the premier event of the Council for the Advancement of Nursing Science (CANS). The poster was selected for inclusion in the meeting in part because it summarizes new research of importance to nurses.

"The research reported in this poster suggests several important conclusions," says Cynthia Chernecky, PhD, RN, AOCN, FAAN, the poster's lead author. "First, IV connector design matters in preventing CRBSI and occlusions. Only one manufacturer's devices were effective in this regard based on our study. Second, clinicians shouldn't assume that anti-bacterial coatings are automatically more effective. The best non-anti-bacterial connector we tested far outperformed a silver-coated connector. Third, no connector should be used in a clinical setting unless its effectiveness is evident by our clinical research. That research should include a blood component because blood reflux is a major factor in CRBSI."

The poster had three coauthors: Jennifer Waller, PhD, Denise Macklin, BSN, RNC, and Brenda Caillouet, MPH, BSN, RN, CRNI.

The in vitro study that utilized a blood component took place in two stages. In the first stage, five different connectors were compared for their ability to suppress the growth of various bacteria that cause CRBSI. The researchers found InVision-Plus to be the most effective of those connectors. The device exhibited no consistent colony-forming units (CFUs) of bacteria during the four test days for any of the four bacteria tested.

In the study's second stage, InVision-Plus was compared to two connectors impregnated with antibacterial agents. Both InVision-Plus connecters performed well, producing no consistent CFUs.

The FDA recently issued an alert requiring all manufacturers of positive displacement connectors to prove that their devices do not increase CRBSI risk. This is because numerous studies already associate positive displacement connecters with higher rates of CRBSI. Studies also associate negative displacement connectors with higher CRBSI rates, due to higher rates of occlusion.

Notably, the positive and negative displacement connectors in the current research were not able to control bacterial growth, which is consistent with those earlier studies. The ineffectiveness may be due in part to the bacteria-nurturing effect of blood residue in the connectors. The residue is caused by blood reflux. InVision-Plus connectors are not subject to blood reflux, which may help explain their effectiveness in the current study.

The poster's data on occlusions is based on research by co-author Brenda Caillouet at a nationally prominent cancer center in Houston, Texas. InVision-Plus was implemented at the center because center's cancer patients are severely ill with compromised immune systems, making them unusually vulnerable to infections.

CRBSI are one of the leading hospital-acquired infections and one of the nation's leading killers overall. They are fatal in up to 25 percent of cases and cost an estimated $34,000 to $56,000 per incident to treat, according to the Institute for Healthcare Improvement.

"It's an honor to be selected for presentation at the CANS congress because only studies that are considered to advance nursing science are chosen," says Chernecky, "But what's most important here is the recognition that choosing the safest, evidence-based IV connector plays a vital role in preventing occlusions and potentially fatal infections."

The CANS congress was held Sept. 27-29 in Washington, D.C.