Although measures to prevent nosocomial bloodstream infections (NBSIs)—shown to increase length of hospital stay, readmissions, costs, and fatality rates—have been heavily studied in intensive care units (ICUs), data focused on non-ICU patients has been limited. Hadar Mudrik-Zohar, MD, and colleagues prospectively investigated positive cultures suspected of being hospital-acquired in unit-based settings. A structured electronic survey was administered to healthcare profes- sionals in units with blood cultures flagged for NBSIs. The survey asked the healthcare professionals to determine how the infection was acquired and what risk factors contributed. A summary was then generated from the information gathered and distributed to the departments as well as to hospital administration.

Results of the intervention were assessed by Dr. Mudrik-Zohar and colleagues, who wrote in Infection Control & Hospital Epidemiology,“Increasing staff awareness of preventable NBSI risk factors is a crucial step in reducing NBSI incidence. We assumed that self investigation of NBSI events, conducted by healthcare providers (physicians and nurses without formal training in infection control practice) of patients who acquired NBSI ‘under their watch,’ might effectively increase staff awareness.” The study’s objective was to explore the impact of department-level NBSI investigations.

Beginning in 2016, data and NBSI rates were examined based on positive blood cultures reported by the microbiology laboratory. An NBSI was defined based on rigorous criteria, including when the blood was drawn and whether a skin contaminant was possible.

The periods before and after the intervention (2014-2015 vs 2016-2018) were compared using interrupted time series analysis.

Among 8,169 positive cultures, 4,135 were classified as clinically significant bloodstream infections (BSI); the remainder were excluded. Of the classified BSIs, 1,237 events were defined as NBSIs.

Of the NBSI events identified, 475 events occurred in patients hospitalized in the internal medicine department, and 206 occurred in the surgical department. Among adult ICU patients, 130 events occurred, and among pediatric ICU patients, 77 events occurred.

The most common sources of infection were catheter-associated urinary tract infection (17%), central and peripheral IV lines (14%), and intra-abdominal infection (9%). In terms of mortality, 334 patients identified as having NBSIs died in the hospital or within 30 days of acquiring the infection and 457 died within a year. Rehospitalization occurred in 28% of patients with NBSIs.

Intervention Impacts

Of the 1,237 NBSI events identified (Table), 590 were recorded before the intervention was implemented and 647 were recorded after. The rate of NBSIs decreased from 4.58 per 1,000 hospital admissions in 2014 and 4.82 in 2015 to 3.81 in 2016, 2.94 in 2017, and 2.86 in 2018. Four months after the intervention was introduced, the NBSI rate per 1,000 admissions decreased by 1.33 (95% CI, −2.58 to −0.07; P=0.04). The study team also observed that monthly NBSI rates continued to decrease by 0.03 during the intervention period (95% CI, −0.06 to −0.002; P=0.03).

Dr. Mudrik-Zohar and colleagues concluded that “This hospital-wide intervention demon- strated that self-investigations of NBSI events conducted by care providers increased front-line ownership and staff awareness, improved understanding regarding true NBSI rates and characteristics, and resulted in a long- lasting decrease of NBSI rates throughout the hospital.”