Bloodstream infection is common in the UK and has significant mortality depending on the pathogen involved, site of infection and other patient factors. Healthcare staffing and ward activity may also impact on outcomes in a range of conditions, however there is little specific National Health Service (NHS) data on the impact for patients with bloodstream infection. Bloodstream Infections – Focus on Outcomes is a multicenter cohort study with the primary aim of identifying modifiable risk factors for 28-day mortality in patients with bloodstream infection due to one of six key pathogens.

In this study by Evans, et al. (2020), adults under the care of five NHS Trusts in England and Wales between November 2010 and May 2012 were included. Multivariable Cox regression was used to quantify the association between modifiable risk factors, including staffing levels and timing of appropriate therapy, and 28-day mortality, after adjusting for non-modifiable risk factors such as patient demographics and long-term co-morbidities.

A total of 1,676 patients were included in the analysis population. Overall, 348/1676 (20.8%) died within 28 days. Modifiable factors associated with 28-day mortality were ward specialty, ward activity (admissions and discharges), movement within ward specialty, movement from critical care, and time to receipt of appropriate antimicrobial therapy in the first seven days. For each additional admission or discharge per 10 beds, the hazard increased by 4% (95% CI 1 to 6%) in medical wards and 11% (95% CI 4 to 19%) in critical care. Patients who had moved wards within specialty or who had moved out of a critical care ward had a reduction in hazard of mortality. In the first seven days, hazard of death increased with increasing time to receipt of appropriate antimicrobial therapy.

The researchers emphasize that this study underlines the importance of appropriate antimicrobials within the first seven days, and the potential for ward activity and ward movements to impact on survival in bloodstream infection.

Reference: Evans RN, et al. Modifiable healthcare factors affecting 28-day survival in bloodstream infection: a prospective cohort study. BMC Infectious Diseases. Vol. 20, No. 545. 2020.