When University of Nebraska Medical Center in Omaha introduced a new blood draw system, it saw an 88 percent decrease in contaminated samples, according to a study published in May in Clinical Infectious Diseases.
If a blood sample is contaminated — usually because skin fragments with bacteria enter the sample — it can increase the risk of a misdiagnosis that could ultimately lead to unnecessary treatment.
"[C]ontaminated blood cultures are a big deal," said Mark Rupp, MD, professor and chief of the UNMC Division of Infectious Diseases and medical director of the Department of Infection Control & Epidemiology at Nebraska Medicine. "Physicians can be led astray and patients may be harmed by additional tests and unnecessary antimicrobial therapy."
The study, led by Dr. Rupp, included 904 patients who each got their blood drawn twice — once with standard procedure and once using a new device, the SteriPath initial specimen diversion device, to see if the novel device reduced blood sample contamination.
The ISDD is unique because it takes the first 1.5 to 2 milliliters of blood, which is the most likely to be contaminated, and diverts it from the main sample.
When UNMC implemented the ISDD device, it saw its false positive rate drop from a baseline of 1.78 percent down to 0.2 percent, an 88 percent reduction.
"The 1.78 percent baseline rate of contamination may seem small, but we should strive to decrease adverse events to the lowest possible level because of the impact to the patient and the burden on the healthcare system," Dr. Rupp said. "We quite clearly showed the rate of contamination was significantly reduced, and that decrease has a very big impact."
Nationwide, 0.6 to 6 percent of all blood samples are contaminated, according to Dr. Rupp.
The study was supported by Magnolia Medical Technologies, which makes the ISDD.