# P-2026. Quality Improvement Initiative to Safely Reduce Follow-up Blood Cultures through Diagnostic Stewardship During a National Blood Culture Bottle Shortage

## TL;DR

This study shows how a quality improvement initiative reduced unnecessary blood culture orders during a shortage, without harming patient outcomes.

## Contribution

A successful diagnostic stewardship program to reduce paired follow-up blood cultures during a national shortage.

## Key findings

- A 36% reduction in paired follow-up blood cultures after implementing stewardship interventions.
- A 39% increase in single-set follow-up blood cultures with no adverse patient outcomes.
- Significant reductions in paired FUBC for S. aureus bacteremia and candidemia.

## Abstract

Blood cultures (BC) are a critical resource to diagnose bloodstream infections. However, over-ordering may lead to antibiotic overuse and increased hospital cost, length of stay, and contamination rates. A national blood culture bottle shortage prompted diagnostic stewardship of follow-up blood cultures (FUBC) in patients monitored for clearance of a prior positive BC, or with new/worsening symptoms after initial negative BC. We aimed to reduce the use of paired-set FUBC and increase single-set FUBC.

This study was performed from 2/18/2024 to 11/23/2024 at a network of 8 academic and community hospitals in New York. Prior to stewardship interventions, clinicians were free to order any number of FUBC at a time. In August 2024 we implemented a series of iterative PDSA (PlanDoStudyAct) cycles to guide clinicians toward appropriate ordering of FUBC including educational memos, limiting the ability to order more than one BC at a time, an electronic best practice advisory to limit BC orders with a prior negative within 72 hours, and a new order panel for BC that defaulted FUBC to a single set. Our goal was a >10% reduction in paired FUBC. QI methodology assessed special cause, descriptive statistics were used to compare pre- and post-intervention characteristics and balancing measures, and data were analyzed using R software.

Over the study period 168,779 BC were ordered, of which 11% were from community hospitals. Demographic characteristics were similar before and after intervention. Prior to our QI project, 29% of BC were FUBC, of which 59% were paired sets. After the series of PDSA cycles there was a 39% increase in single FUBC, a 36% reduction in paired FUBC, and an overall 3.3% reduction in total blood culture bottle use (p = 0.002). There were no differences in the length of stay, in-hospital mortality, or 30-day readmission. Reduced paired FUBC usage was also seen in S. aureus bacteremia (44%) and candidemia (45%) (p < 0.001).

We exceeded our goal of reducing paired FUBC through targeted clinical decision support while successfully increasing single-set FUBC. Outside of a blood culture bottle shortage, future iterative changes are needed to support the use of FUBC in S. aureus bacteremia and candidemia.

Lars Westblade, PhD, Elements Materials Technology: Grant/Research Support|Hardy Diagnostics: Grant/Research Support|Melinta Therapeutics: Grant/Research Support|Selux Diagnostics: Grant/Research Support|Shionogi: Advisor/Consultant|SNIPRBIOME: Grant/Research Support