NEW YORK (Reuters Health) – Bloodstream infections are more common with the use of needle-free mechanical valve connectors in intravascular catheters, a new study shows.

The needle-free mechanical valve connectors were introduced to replace needle connectors, partly in order to reduce needlesticks, according to the report in the December 15th Clinical Infectious Diseases.

“Our study is the first to assess infection control practices during the split septum and Luer access negative or positive pressure mechanical valve periods,” lead author Dr. William R. Jarvis from Jason and Jarvis Associates, Hilton Head Island, South Carolina told Reuters Health by email. “The infection control practices were more enhanced during the mechanical valve period, and still the central venous catheter- associated bloodstream infection rate increased significantly.”

Dr. Jarvis and associates compared health care-associated bloodstream infection rates on wards or intensive care units at 5 hospitals in the U.S. and Australia that had converted from split septum connectors or needles to mechanical valve needleless connectors.

Rates of health care-associated bloodstream infection increased in all ICUs and wards after the switch to needle-free connectors, the authors report.

When data from all 16 ICUs were combined, the bloodstream infection rate per 1000 central venous catheter days rose from 6.1 before the use of mechanical valve needle-free connectors to 9.5 after their introduction.

These increases persisted despite repeated reinforcement of bloodstream infection prevention strategies in all the involved units and wards, the investigators say.

In hospitals that switched back to split septum connectors, the infection rate per 1000 central venous catheter days fell from 9.5 before the switch to 5.8 afterward, a rate similar to what was seen needle-free connectors were adopted.

Dr. Jarvis advised, “Be sure you know which type of mechanical valve you have (positive pressure/displacement, negative pressure or neutral pressure) and know what infection control recommendations (i.e., when to clamp and disinfect) you should be using.” He said health care providers often don’t realize their institution stocks more than one type of connector, “so appropriate infection control practices are not applied.”

Then, he continued, “make sure you scrub the hub during any manipulation of the needleless connector” with 70% alcohol or 2% chlorhexidine for at least 15 to 30 seconds,

“Infusing blood through the connector, withdrawing blood through the connector, and infusion of lipid or TPN through the connector can increase the risk for central venous catheter-associated bloodstream infections,” Dr. Jarvis added.

The researchers also warn that Centers for Disease Control guidelines — which state that needle-free mechanical valve connectors do not affect the incidence of catheter-related bloodstream infections – are outdated. Instead, they say, “Appropriate mechanical valve needleless connector infection control practices should be derived from more recent publications and the Society for Healthcare Epidemiology of America…compendium.”

Reference:
Clin Infect Dis 2009;49:1821-1827.