Asynchronous Testing of 2 Specimen-Diversion Devices to Reduce Blood Culture Contamination: A Single-site Product Supply Quality Improvement Project

Monica Arenas, Gracia M Boseman, John D Coppin, Janell Lukey, Chetan Jinadatha, Dhammika H Navarathna from Central Texas Veterans Health Care System

Blood culture contamination above the national threshold has been a consistent clinical issue in the ED setting. Two commercially available devices were examined that divert an initial small volume of the specimen before the collection of blood culture to reduce skin contamination.

Prospectively, 2 different blood culture-diversion devices were made available in the unit supplies to ED clinicians at a single site during 2 different periods of time as a follow-up strategy to an ongoing quality improvement project. Blood samples were collected in the emergency department over a period of 16 months. A retrospective record review study was conducted comparing the use of the 2 specimen-diversion devices with no device (control group) for blood culture contamination rates. The main outcome of monthly blood culture contamination per device was tested using a Bayesian Poisson multilevel regression model.

A total of 4030 blood samples were collected and analyzed from November 2017 to February 2019. The model estimated that the mean incidence of contaminated blood draws in the device A group was 0.29 (0.14-0.55) times the incidence of contaminated draws in the control group. The mean incidence of contaminated blood draws in the device B group was 0.23 (0.13-0.37) times the incidence of contaminated draws in the control group, suggesting that initial-diversion methods reduced blood culture contamination.

Initial specimen-diversion devices supplement present standard phlebotomy protocols to bring down the blood culture contamination rate.

Reducing False-Positive Blood Cultures: Using a Blood Diversion Device

David M. O’Sullivan and Lee Steere, Hartford Hospital, Hartford, CT.

Determining if and when a patient receives antibiotic therapy can be a life saving decision. If a person has an infection, starting antibiotics early is important;  however if a person does not need the antibiotics, starting them has significant financial and health-related consequences.

To evaluate if a minimal-risk blood diversion device could be used successfully to reduce the rate of false-positive blood cultures.

The false-positive blood culture rate (FPR) was compared for three months using a blood diversion device and three months not using a blood diversion device.

There was a significantly lower rate of FPR during use of the blood diversion device (0.44%), compared with an average of 1.71% for the three months not used, an average reduction of 74.1%.

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Passive Engineering Controls Result in Sustained 66% Reduction in Blood Culture Contamination

Monica Baxter, Carolyn Cook and Angie James from St. Mary’s Regional Medical Center, Russellville, AR.

Blood culture testing is an important diagnostic tool in identifying the presence of microbes in the bloodstream. Tests are frequently contaminated, leading to false-positive results. Blood culture contamination can result in unnecessary antibiotic treatment, extended hospital length of stay, and patient exposure to hospital-acquired conditions.

St. Mary’s Regional Medical Center (SMRMC) in Russellville, Arkansas, struggled with blood-culture contamination rates, with an average of 6.8% from 2014 to 2018. Ongoing staff education yielded a reduction to an average of 5%. In an effort to reduce the contamination rates, our facility elected to try a novel specimen diversion device. Laboratory and emergency department (ED) staff were educated on the diversion device prior to the initiation of the trial period. Compliance with the diversion device averaged 70%–75% during the trial period. Monitoring of contaminations was added to our daily safety huddle to provide a quick turnaround time for false-positive education to specific clinical staff.

The results were significant, with a decrease in contamination rates from 4.93% to 1.66%—a 66% reduction. Improved blood culture testing has several advantages: best practice for patient care is first and foremost, along with other financial benefits for the facility. Several articles have estimated the cost of a contaminated culture to be $3,000–$10,000 per event; SMRMC has adopting an estimated cost of $4,000. The number of cultures at our hospital averages ~4,400 per year, and these results suggest a savings of >$500,000 per year (as contaminations on an annual basis fell from 217 to 73). With this intervention, 144 patients were spared from receiving unnecessary antibiotics as a result of a false-positive blood culture testing.

We conducted a brief analysis to determine whether there was any obvious change in length of stay for patients with a false-positive blood culture compared to those with true negative results. In analyzing data for 3 different months, patients with contaminated cultures spent an average of 3.97 additional days in the facility. In conclusion, the implementation of this specimen diversion device significantly lowered our contamination rates, was integrated into practice, and has provided clinical and financial benefits.

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The Impact of Blood Culture Diversion Devices on Contamination Rates

Monica E. Arenas, Janell Lukey, Grace Boseman, Dhammika Navarathna
Central Texas Veterans Health Care System, Temple, TX

False positive blood cultures (BC) are associated with unnecessary hospitalization and/or extended length of stay with consequent financial burden. Our historical data shows that the majority of the false positive blood cultures are from the Emergency Department (ED). After repeated attempts of training, blood culture contaminations persisted at an unacceptable rate. Therefore, we recently [trialed] two different types of FDA 510(k)-approved devices* designed to eliminate blood culture contamination by sequestering the initial few drops of blood (first draw) which is considered to carry contaminant flora. It has been shown [that] the bacteria which colonize the human skin are not only on the surface but deeper in the skin as well. The Steripath and Kurin devices divert the initial small volume of blood as to remove any potential skin plug [which] contains contaminants.

Steripath® Blood Culture Collection System

  • This is a single use sterile blood culture collection system.
  • SteriPath® is designed for initial blood specimen diversion using a preassembled vein-to-bottle closed system that mechanically diverts and sequesters the initial 1.5 to 2 mL of blood into a proprietary isolation chamber.

Kurin® Blood Culture Collection System

  • This device is a sterile, single use blood culture collection set. The Kurin® device consists of a winged needle with flexible tubing and an attached vial adapter required for venipuncture to draw blood culture samples.
  • The Kurin blood capture device sequesters the initial draw of blood upon venipuncture. The set is provided with a safety shield for covering the used needle prior to disposal.
  • The amount of blood diverted is very small, estimated to be 0.2-0.1 mL.

*Correction: as of June 2019, the Steripath device had not received 510(k) clearance.


  • Appropriate aseptic technique and the use of Steripath® or Kurin ® devices made a remarkable decrease in contamination [in the] ED.
  • Reduced false positive cultures and eliminated additional resources for workup are cost beneficial.
  • Avoid unnecessary antibiotic treatment and hospitalization days.
  • Initial specimen diversion volumen variation from 0.2ml–2ml did not have a significant impact on contamination rate.

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Magnolia Medical Technologies. (2015) The SteriPath System.

Kurin, manufactured in San Diego, CA has received FDA 510(k) market clearance.

Innovation for reducing blood culture contamination: Initial Specimen diversion technique. Patton RG, Schmitt T. J Clin Microbiol. 2010 Dec;48(12):4501-3. 

Reducing blood culture contamination in the emergency department: an interrupted time series quality improvement study. Self WH, Speroff T, Grijalva CG, McNaughton CD, Ashburn J, Liu D, Arbogast PG, Russ S, Storrow AB, Talbot TR. Acad Emerg Med. 2013 Jan;20(1):89-97.

Preventing Blood Culture Contamination using a Novel Engineered Passive Blood Diversion Device

Jared Sutton, MPH, CIC; Paula Fritsch, MPH, MT, CIC; Marybeth Moody, MT(ASCP), SM; Kesha Dinaro, MSN, RN, CEN; Clinton Holder, MD. Bayfront Health St. Petersburg, St. Petersburg, FL

Blood culture contaminants lead to increased empirical antibiotics usage, contributing to antibiotic associated colitis, multi-drug resistant bacteria, and increased risks for drug interactions. Quality improvement programs have led to complex costly blood culture collection bundles, including sterile kits, blood diversion tubes, and advanced skin preps, all with the goal of reducing blood culture contaminants. Despite current interventions contamination continues to occur because bacteria reside deep in the dermis where antiseptics cannot penetrate. This study investigates the efficacy of an engineered passive blood diversion device in preventing blood culture contaminates.

This quasi-experimental study focused on blood cultures collected by phlebotomy and the emergency department between January and September 2017 (Pre: Jan – April, Post: May – September). The ratio of contamination was evaluated using a chi-square test at a 0.05 alpha level. The intervention was only indicated for vacutainer draws during the study period, but stratifying the pre-intervention data for vacutainer collections was not possible. For this reason, this study focuses on total blood culture contaminants, and not just vacutainer collections. Without stratification, the mentioned results are what a user could expect to reproduce in a “real world” scenario.

Results from 4220 blood cultures were analyzed. The pre- intervention period included 1953 cultures with a contamination rate of 0.025, 95% CI [0.019, 0.033]. The post-intervention period included 2267 cultures and a contamination rate of 0.012, 95% CI [0.008, 0.017]. A chi-square statistic was calculated to examine if the intervention reduced blood culture contamination. The test was found to be statistically significant, X2(1, N = 2852) = 10.979, p < 0.05.

Intervention Design Variations

Blood Culture Contaminant Control Chart

Intervention Cost Analysis

The results suggest that there is a relationship between the proportion of a blood culture contaminants and the type of device used. This may be more apparent given that the intervention was not indicated for all types of blood draws during the study period. It appears that this product can potentially reduce blood culture contaminants, but more research is required.

Study Limitations

  • The studied intervention is not indicated for use for all types of blood draws.
  • Intervention was utilized in 50% of blood draws during the post intervention period.
  • During the first 3 months of post Intervention period, the trial device was not indicated for use in 8 out of 9 contaminated cultures.
  • In the post study period, the device was redesigned to allow for different types of blood cultures (ex. draws from a freshly placed IV).

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Bekeris, Leonas G., et al. “Trends in blood culture contamination: A College of American Pathologists Q-Tracks study of 356 institutions.” Archives of Pathology and Laboratory Medicine 129.10 (2005): 1222-1225.

Garcia, Robert A., et al. “Multidisciplinary team review of best practices for collection and handling of blood cultures to determine effective interventions for increasing the yield of true-positive bacteremias, reducing contamination, and eliminating false-positive central line–associated bloodstream infections.” American journal of infection control 43.11 (2015): 1222-1237.

Hall, Keri K., and Jason A. Lyman. “Updated review of blood culture contamination.” Clinical microbiology reviews 19.4 (2006): 788-802.

Self, Wesley H., et al. “Cost analysis of strategies to reduce blood culture contamination in the emergency department: sterile collection kits and phlebotomy teams.” Infection Control & Hospital Epidemiology 35.8 (2014): 1021-1028.

Not Your “Average” ED: A CNS-Led Project That Reduced Blood Culture Contaminations in One Emergency Department to Below Expected Levels

Michael Allain, MS, RN, ACNS-BC, CCRN, Crouse Hospital

At the 2018 National Association of Clinical Nurse Specialists Conference, Michael Allain, MS, RN, ACNS-BC, CCRN, emergency services clinical nurse specialist at Crouse Hospital in Syracuse, New York, presented results related to the use of a novel FDA-cleared blood culture collection device that diverts the initial aliquot of blood to help hospitals in their efforts to reduce contaminated blood cultures (CBCs)

According to Allain, contamination makes interpreting results difficult and can cost millions of dollars. To address the issue at Crouse, Allain, in conjunction with the hospital’s phlebotomy manager, implemented strategies to reduce contamination in 2012. They provided department-wide education, limited who drew blood cultures, and closely monitored compliance on monthly basis. The overall contamination rate from 2013-2016 ranged from 2.1% to 1.6%.

In January 2017, the CNS for the emergency department re-evaluated the current state of blood culture collection at the hospital and revised its evidence-based protocol. At the same time, Crouse began using Kurin®, a blood culture collection set with an automated specimen diversion device that diverts skin microbes. Allain reported significant reductions in contaminated blood culture rates and associated costs post intervention. Accounting for the cost of the Kurin device, Allain calculated that the hospital would save more than $185,000 per year.

Allain concluded the abstract acknowledging that even a hospital operating at the acceptable CBC benchmark rate, can further lower their CBC rate with this process improvement inclusive of education, compliance monitoring, and the use of Kurin blood collection device with automated specimen diversion.

In 2018, the National Association of Clinical Nurse Specialists (NACNS) received 267 abstracts for consideration. Every abstract underwent blind peer review by 3 reviewers and their scores were averaged. This abstract was among the highest scoring abstracts submitted to the conference.1

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1 Horner SD. Top Scoring Abstracts From the 2018 National Association of Clinical Nurse Specialists Annual Conference. Clinical Nurse Specialist. May/June 2018