Especially for busy hospital emergency departments, avoiding blood culture contamination is a constant challenge for those tasked with collecting blood culture specimens
Better, faster diagnosis and treatment of sepsis continues to be a major
goal at hospitals, health networks, and other medical facilities throughout the
United States. Yet microbiologists
and clinical
laboratory managers continue to be frustrated with how frequently
contaminated blood culture specimens show up in the laboratory.
A recent poll of more than 200 healthcare professionals who
attended a
sponsored webinar hosted by Dark Daily, showed that nearly 10% of
those who responded reported an overall blood culture contamination rate in
their hospitals at above 4%.
However, the arrival of new technology may provide hospital
staff with a way to reduce contamination rates in blood culture specimens, in
ways that improve patient outcomes.
The effectiveness of a new tool, the Steripath Initial Specimen Diversion
Device (ISDD), is being demonstrated in a growing number of prominent
hospitals in different regions of the United States. What will be particularly
intriguing to clinical laboratory professionals is that the ISDD is capable of
collecting blood while minimizing the problems caused by human factors, micro-organisms,
and skin plugs or fragments. This device was developed by Magnolia Medical Technologies
of Seattle, Wash.
The ISDD isolates the initial 1.5
to 2.0 mL aliquot of the blood culture sample, which is most likely to be
contaminated with microscopic skin fragments colonized with bacteria. The device diverts this initial aliquot into a sequestration
chamber, mechanically isolating it from the rest of the sample, and then
automatically opens an independent sterile pathway into blood culture collection
bottles.
Such technology may be welcomed by medical laboratory
professionals based in hospitals and other healthcare facilities. That’s
because it is the lab staff that typically identifies a contaminated blood
culture specimen and must go back to the nurses, staffers, and physicians on
the wards to have them redraw an acceptable specimen that will produce an
accurate, reliable result. Patients under these circumstances generally
continue on unnecessary broad-spectrum antibiotics, and their length of stays
have been reported to increase by two days on average.
Problem of Decentralized Phlebotomy
One problem contributing to high blood culture rates is
that, in many hospitals and health networks, phlebotomy has been decentralized
and is no longer managed by the clinical laboratory.
“I’ve seen the havoc decentralized phlebotomy wreaks on contamination rates of blood culture rates,” stated Dennis Ernst, Director of the Center for Phlebotomy Education based in Mio, Mich. “That staffing model, which swept through the hospital industry in the late 1990s, may have looked good on paper, but I can count the number of facilities that have successfully decentralized on the fingers of one hand. And I don’t know of any decentralized setting that has an acceptable blood culture contamination rate.”
Ernst, a medical
technologist and educator, has seen the
difficulty in lowering contamination rates in a decentralized,
multidisciplinary workforce. He has worked for more than 20 years advocating
for best practices in the diagnostic blood collection industry and has helped clinical
laboratory facilities achieve a 90% reduction in their contamination rates. Ernst considers blood
culture contamination to be among the “low-hanging fruit” in every laboratory
that can be easily and permanently corrected with the proper approach.
“One statistic we’ve heard over and over again is that the American Society of Microbiology established the ‘threshold’ for blood culture contamination to be 3%,” Ernst said. “I believe strongly that a 1% contamination rate or less is what should be required and that it’s not only achievable, but sustainable.”
Regardless of
staffing mix, blood culture contamination is a common problem in the emergency
department, Ernst explained during his presentation, “Evidence-Based
Technology to Reduce Blood Culture Contamination, Improve Patient Care, and
Reduce Costs in Your Clinical Lab or Hospital,” which is available
free for streaming.
Improving Patient Care and Reducing Avoidable Costs
With unnecessary
antibiotic use, increased length of stay, and the cost of unnecessary
laboratory testing at issue, hospitals are tracking blood culture collection
results and exploring ways to reduce episodes of blood culture contamination. On these and other healthcare quality
improvement aims, providers are publishing study results on contamination
reduction and potential direct and indirect hospital cost savings. For example:
At the University of Nebraska, a
prospective, controlled, matched-pair clinical study showed an 88% reduction in
blood culture contamination with a 12-month sustained rate of 0.2% when
Steripath was used by phlebotomists in the ED. The author estimated the institution
would save approximately $1.8 million if the technology was adopted
hospitalwide, reported an article in Clinical
Infectious Diseases in July 2017.
Florida-based Lee
Health system’s microbiology laboratory reported an 83% reduction in
contamination rates comparing their standard method to ISDD for a seven-month
trial period. Their systemwide potential cost avoidance estimates ranged from
$4.35 million to nearly $11 million, reported an article in the Journal of Emergency
Nursing in November 2018.
Researchers from Massachusetts General reported that
ISDD is the single most effective intervention so far explored for reducing
costs related to false-positive blood cultures, potentially saving the typical
250- to 400-bed hospital $1.9 million or $186 per blood culture and preventing
34 hospital-acquired conditions (including three C.
difficile cases). The recent article “Model to Evaluate the Impact of
Hospital-based Interventions Targeting False-Positive Blood Cultures on
Economic and Clinical Outcomes” in the Journal
of Hospital Infection explains more.
Blood Facilities Should be Tracking Their Contamination
Rate
One of the biggest challenges faced during blood sample
collection is making sure an organism is not inadvertently introduced into the
blood. Therefore, importance has been placed on clinical laboratories and other healthcare providers
developing policies and procedures to limit the introduction of likely
contaminants.
“I believe most places monitor blood culture contamination,
but they are not doing much that is effective to reduce it,” Ernst said.
“That’s a real problem.”
To assist healthcare providers in blood culture quality
improvement, the free webinar, “Evidence-Based Technology to Reduce Blood
Culture Contamination, Improve Patient Care, and Reduce Costs in Your Clinical
Lab or Hospital,” available on-demand through Dark Daily, can be
downloaded by clicking here,
or by pasting the URL “https://darkintelligenceprogramsondemand.uscreen.io/programs/evidence-based-technology-to-reduce-blood-culture-contamination-improve-patient-care-and-reduce-costs-in-your-clinical-lab-or-hospital”
into a web browser.
This program, which polled more than 200 healthcare
professionals, explores the clinical and economic significance of blood culture
contamination, the downstream impact of false-positive blood cultures, and case-study
evidence of sustained reductions in contamination.
Additionally, the device also could help reduce antibiotic-resistant infections and other HAIs and HACs, though this result was not part of the study
Research findings indicate how a new system-in-a-box device that phlebotomists and clinical laboratories would use when drawing blood could reduce contamination of blood cultures and lower patients’ use of antibiotics. In a study involving 1,800 blood cultures done on 904 patients at the University of Nebraska Medical Center (UNMC), use of the device was attributed to an 88% reduction in the blood culture contamination rate.
According to a press release by researchers at UNMC who studied the device, “With traditional blood draws, about 30% to 40% of patients with contaminated blood cultures are prescribed antibiotics unnecessarily. This contributes to antibiotic resistance and undermines nationwide efforts to improve antimicrobial stewardship.” The researchers reported their findings in an article published in the Oxford Academic journal Clinical Infectious Diseases (CID).
Blood Culture Contamination Harms Patients and Increases Cost of Care
The UNMC researchers noted that, during a blood draw, a significant percentage of blood cultures become contaminated when skin fragments containing bacteria are dislodged and mix with the patient’s blood. For the thousands of patients each day who have their blood drawn, contaminated blood cultures, which lead to false positive results for sepsis, often result in unnecessary antibiotic treatment. This in turn can lead to serious and deadly antibiotic-resistant infections with various multi-drug-resistant organisms such as Clostridium difficile infection (C. diff), as well as, other hospital-acquired infections and conditions (HAIs & HACs) due to unnecessary extended length of stay, according to Mark Rupp, MD, Professor, Department of Internal Medicine, Section of Infectious Diseases, and Medical Director, Department of Healthcare Epidemiology-Infection Control at UNMC.
In the CID article, Rupp and colleagues reported on a prospective, controlled trial conducted in the emergency department (ED) at UNMC’s partner hospital Nebraska Medicine. Results of the trial showed that the SteriPath ISDD diverts and sequesters the first 1.5 to 2 mL portion of blood. The researchers presumed that these initial drops of blood would contain the contaminating skin cells and microbes.
SteriPath is a self-contained, preassembled, sterile blood collection system. It provides proprietary vein-to-bottle technology that significantly reduces blood culture contamination, according to Magnolia Medical Technologies. This could be useful for helping phlebotomists and clinical laboratories improve the quality of specimens collected for use in blood culture testing. Click on the image above to view videos on the SteriPath ISDD. (Photo copyright: Magnolia Medical Technologies.)
The researchers tested the SteriPath ISDD during standard phlebotomy procedures in patients requiring blood cultures. After drawing 1,808 blood cultures from 904 study subjects, the researchers concluded that the ISDD significantly reduced blood culture contamination compared with standard phlebotomy procedures. The blood culture contamination among phlebotomists who used the ISDD decreased by nearly 90%, compared to phlebotomy procedures conducted by nurses who did not use the ISDD.
“We were able to decrease the false positive rate significantly through use of this device—from 1.78% down to 0.2%, which represents an 88% reduction,” Rupp noted in the UNMC press release. “The 1.78% 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 to our healthcare system.
“The device is innovative in that it diverts the first couple of milliliters of blood into the sequestration chamber,” Rupp explained. “That’s where we think the contaminants are. The remaining blood being drawn is then diverted into the sterile pathway into the blood culture vial, thereby preventing the contamination.”
Billions of Healthcare Dollars Could Be Saved with SteriPath’s ISDD
During a conference call with reporters, Rupp admitted that cynics might scoff at such a low rate of improvement. “Many of those folks don’t understand that we do tens of millions of blood cultures in this country every year,” he explained. “Every year, we do about 30 million or so blood cultures. That many cultures means a 2% contamination rate equates to somewhere in the neighborhood of about 600,000 contamination events. And 2% is a very respectable level. Usually clinicians are satisfied anywhere below about 3%, which is about 900,000 events each year.”
For about 40% to 50% of patients whose blood is contaminated, physicians will prescribe antibiotics, order another blood test, and require patients to stay several days in the hospital, he added. “All of this results in thousands of extra dollars being spent,” he declared. If each blood contamination case costs about $4,000, then reducing such contamination in potentially 600,000 cases each year could save more than $1 billion healthcare dollars.
According to the researchers, costs associated with blood culture contamination ranged from $1,000 per patient in 1998 to $8,700 per patient in 2009. “If a midpoint cost estimate of $4,850 is used, and the added cost of the device is not taken into account, it equates to a cost avoidance of $1.8 million per year at our institution alone,” Rupp stated. “If the low rate of contamination that we observed in the study, 0.22%, was applied to all blood cultures throughout the country, billions of dollars of excess costs could be avoided.”
This clinical study offers strong evidence that the SteriPath ISDD might prove to be a useful tool that clinical laboratories could use to help prevent unnecessary exposure to antibiotics and hospital stays, lower healthcare costs, and improve patient test outcomes. If the UNMC clinical study outcomes are replicated in future studies, then it is a technology and a solution that has the potential to be adopted by phlebotomists in medical laboratories and hospitals.