The following is a summary of “Blood Culture Ordering Increases Post-SEP-1 Bundle: Overcultured ED Discharges,” published in the May 2023 issue of Emergency Medicine by Sterk et al.

In 2015, the Severe Sepsis and Early Septic Shock Management Bundle (SEP-1) conditioned hospital reimbursement on performance on time-sensitive indicators, such as ordering blood cultures for patients with severe sepsis or septic shock. This metric could have significantly influenced Emergency Department (ED) requesting practices for patients without severe sepsis or septic shock. In this study, researchers aimed to determine if the frequency of blood culture orders on adult patients discharged from the ED changed after the SEP-1 metric, if the rates of positivity for pathogens or contaminants changed after the SEP-1 metric, and if similar changes were observed in the frequency of orders for other laboratory tests. This was a retrospective analysis of blood culture prescriptions for adult ED patients discharged from a suburban academic hospital from January 1, 2012, through June 30, 2019. They compared the number of blood cultures per adult patient released before and after implementing the SEP-1 metric.

Each culture that grew an organism was classified as either a pathogen or a contaminant, and the growth rates of pathogens and contaminants were compared before and after SEP-1. Before and after the implementation of the SEP-1 metric, they reached the order rates of blood cultures and lactates as labs related to SEP-1 with the order rates of D-dimers, lipases, human chorionic gonadotropins (HCGs), and brain natriuretic peptides (BNPs) as labs unrelated to SEP-1. During the research period, 144,343 adult patients were discharged from the ED. From these 3,827 patient encounters, 6,754 blood cultures were drawn. The rate increased by 76.2% (P< 0.001) from 43.1 cultures per 1,000 discharged patients before the SEP-1 metric to 75.9 blood cultures per 1,000 discharged patients. 

The positivity rate in the cultures decreased (from 3.93% before SEP-1 to 3.03% after SEP-1, P = 0.044), while the rate of blood cultures yielding a contaminant remained unchanged (2.49 to 1.85%, P = 0.071). Orders for labs unrelated to SEP-1 rose by an average of 16.8% after the SEP-1 metric, while orders for SEP-1-related laboratories rose by an average of 81.0%. Blood cultures were prescribed more frequently on patients discharged from the ED after the SEP-1 bundle. These cultures had a decreased rate of pathogen positivity and the same rate of contamination growth. The rise in other laboratories did not mirror this increase. These findings suggest that the SEP-1 metric had the unintended consequence of increasing blood culture orders for patients who were healthy enough to be discharged from the emergency department.

Source: sciencedirect.com/science/article/abs/pii/S0735675723000372