In the Fight Against Life-Threatening Catheter Infections, Length of Use Is Key

Hospitals may reduce the risk of life-threatening bloodstream infections in newborns with peripherally inserted central venous catheters by replacing the device every 30 days or so, according to a new Johns Hopkins Children’s Center study.

The daily risk of getting a dangerous bacterial infection jumped by 33 percent per day around day 35 and remained elevated thereafter in those babies who needed the device long term, the investigators write in the April issue of Pediatrics. Their findings will appear online on March 15.

A peripherally inserted central venous catheter (PICC line) is a tube inserted into a peripheral blood vessel in the arm or forearm, and threaded toward the major blood vessels near the lungs and heart. The device provides a temporary portal for medications, food, fluids and blood-draws in critically ill newborns. Because central lines also provide quick access in emergencies, newborns in the neonatal intensive care unit often need the device for weeks or months. However, with prolonged use, the line can become contaminated and allow dangerous bacteria direct entry into a baby’s bloodstream.

“Our findings showed a dramatic increase in daily infection risk for each day beyond day 35,” says lead investigator Aaron Milstone, MD, MHS, a pediatric infectious disease specialist at Hopkins Children’s. “Our message to NICU staff is simple: Remain vigilant and consider replacement around day 35.”

But investigators caution there is no magic day for removing catheters in order to prevent infections. Instead, they advise doctors and nurses to be vigilant about signs of infection, to reassess daily the risk versus the benefit of catheter use in each patient, and to remove the catheter immediately once no longer needed.

“Are we advocating preemptive change of PICC lines in all patients at day 35? We are not. What we are saying is the longer the device stays in, the higher the risk for infection, and day 35 appears to be a critical cutoff point,” Milstone says.

Each year, 80,000 central line infections occur in the United States, researchers estimate, and up to one-fifth of patients who get them will die. In one study of PICU patients, researchers found that each infection prolongs the hospital stay by one week on average and another study showed that these infections can cost up to $29,000 per patient.

In the study of 683 newborns treated at Johns Hopkins between 2006 and 2008, researchers also found that the risk of infection went up by 14 percent per day in the first 18 days after the device is inserted. The risk leveled off between days 19 and 35, and rose precipitously by 33 percent per day between days 36 and 60. The average rate of infection was two infections for every 1,000 catheter days.

Simple precautions, like regularly changing the dressing covering the central line, changing the tubes and caps attached to it, and cleaning the line before and after use can also help keep bacteria at bay, researchers say.

The research was funded in part by the National Institutes of Health.

Other investigators in the study included Arnab Sengupta, MBBS, MPH; Christoph Lehmann, MD; Marie Diener-West, PhD; and Trish Perl, MD, MS.

Conflict of interest disclosure: Lehmann is member of the American Medical Informatics Association and has received an honorarium from Mead Johnson and Pediatrix. Milstone and Perl receive grant support from Sage Products Inc. and Perl is on a data review board for Candace Pharmaceuticals and on an advisory panel for Theradoc Inc., manufacturer of infection surveillance systems. The terms of these arrangements are managed by the Johns Hopkins University in accordance with its conflict-of-interest policies.