Improving Diagnostic Accuracy: Evidence-Based Strategies to Decrease ED Blood Culture Contamination

Blood culture contamination (BCC) is a persistent problem in emergency departments (EDs), where contamination rates are higher compared to the general wards and intensive care units.⁹ BCC contributes to unnecessary antibiotic exposure, excessive diagnostic testing, and increased length of stay. National benchmarks define <3% contamination as acceptable, yet emerging evidence demonstrates continued progress toward a ≤1% goal is achievable.

Medical literature and industry guidelines cite several interventions that have been clinically proven to reduce BCC rates, thus improving diagnostic stewardship. Practice guidelines are provided by Centers for Disease Control and Prevention,³² Clinical and Laboratory Standards Institute (CLSI®),³⁵ Association for Professionals in Infection Control and Epidemiology,⁹⁸ American Society for Microbiology (ASM),³⁹ Infectious Diseases Society of America (IDSA),³⁷ Infusion Nursing Society (INS),³⁶ Emergency Nurses Association (ENA),⁴⁰ and the Association for Vascular Access (AVA).⁹²  

Best practices for improving diagnostic stewardship include adequate skin antisepsis, avoidance of syringe draws and collections from existing lines, proper specimen fill volume, introduction of blood culture collection kits, proper bottle inoculation technique, and initial blood diversion. Additionally, embedding standardized blood culture collection protocols into orientation, annual competencies, and ongoing staff training can promote long-term adherence to best practices and help to sustain low BCC rates.

line

Setting

In early 2023, contamination rates at two EDs within a two-hospital system exceeded the national benchmark of <3%. A quality improvement initiative was launched to standardize blood culture collection practices and implement an evidence-based blood diversion device to reduce contamination and improve diagnostic accuracy.

‍

Method

This project was conducted in two busy EDs. A baseline one-week audit found multiple failure points including inadequate skin antisepsis, lack of initial blood diversion, syringe draws, improper fill volumes, and inconsistent bottle inoculation techniques. A multifaceted intervention began in June 2023 including standardized blood culture collection kits, adoption of a passive diversion, targeted staff education and hands-on competency training, elimination of line draws and real-time feedback with follow-up for contamination events.

‍

BCC rates in two EDs experienced continual decline with Kurin passive diversion.

Baseline contamination rates were evaluated for 12 months pre-intervention, during a 4-month pilot (Sept–Dec 2023), and over a 12-month post-implementation period. Overall, there was a 67% decrease in emergency department A and a 29% decrease in emergency department B. Kurin use effectively Improved diagnostic stewardship by reducing blood culture contamination while ensuring that there were no missed cases of bacteremia or adverse events documented during the intervention periods. As the BCC rates continue to trend downward with one ED falling below 2%, the authors concluded that contamination rates approaching the ≤1% target are achievable in high-volume emergency departments when automatic diversion is paired with staff education and competency validation.

‍

Key takeaways

Standardizing blood culture contamination practices combined with implementation of a diversion device substantially reduced ED blood culture contamination rates improving diagnostic stewardship.

• 67% decrease in BCC rate in ED A and a 29% decrease in ED B with Kurin.

  Over a 4-month trial and 1 year of continued use, Kurin helped to reduce blood culture contamination rates in two high-volume emergency departments by 67% and 29%, respectively.
• No missed bacteremia cases were identified or reported.

  While using Kurin, BCC rates fell with no missed cases of bacteremia among the patient population during the intervention periods indicating improving diagnostic stewardship.
• No adverse events related to the intervention were reported.

  During the 1 year and 4 months of study data collection, the facility documented no adverse events for patients with blood culture testing.