Epidemiology and outcomes of bloodstream infections in patients discharged from the emergency department

Objective: To determine the outcomes of patients discharged from the emergency department (ED) with a bloodstream infection (BSI) and how these outcomes are influenced by antibiotic treatment. Methods: We identified every BSI in adult patients discharged from our ED to the community between July 1, 2002, and March 31, 2011. The medical records of all cases were reviewed to determine antibiotic treatment in the ED and at discharge. Microorganism sensitivities were used to determine whether antibiotics were appropriate. These data were linked to population-based administrative data to determine specific patient outcomes within the subsequent 2-week period: death, urgent hospitalization, or an unplanned return to the ED. Results: A total of 480 adults with BSI were identified (1.49 cases per 1,000 adults discharged from the department). Compared to controls (321,048 patients), BSI patients had a significantly higher risk of urgent hospitalization (adjusted OR 2.1 [95% CI 1.6-2.8]) and unplanned return to the ED (adjusted OR 4.1 [95% CI 3.3-4.9]). Outcome risk was significantly lowered in BSI patients who received appropriate antibiotics in the ED and at discharge. In elderly patients, the risk of urgent hospitalization increased significantly as the time to appropriate antibiotics was delayed. Conclusions: BSI patients discharged from the ED have a significantly increased risk of urgent hospitalization and unplanned return to the ED in the subsequent 2 weeks. These risks decrease significantly with the timely provision of appropriate antibiotics. Our results support the aggressive use of measures ensuring that such patients receive appropriate antibiotics as soon as possible.