Institution of an emergency department "swarming" care model and sepsis door-to-antibiotic time: A quasi-experimental retrospective analysis

Background Prompt sepsis treatment is associated with improved outcomes but requires a complex series of actions by multiple clinicians. We investigated whether simply reorganizing emergency department (ED) care to expedite patients' initial evaluation was associated with shorter sepsis door-to-antibiotic times. Methods Patients eligible for this retrospective study received IV antibiotics and demonstrated acute organ failure after presenting to one of three EDs in Utah. On May 1, 2016, the intervention ED instituted "swarming" as the default model for initial evaluation of all mid- and low-acuity patients. Swarming involved simultaneous patient evaluation by the ED physician, nurse, and technician followed by a team discussion of the initial care plan. Care was unchanged at the two control EDs. A 30-day wash-in period separated the baseline (May 16, 2015 to April 15, 2016) and post-intervention (May 16, 2016 to November 15, 2016) analysis periods. We conducted a quasi-experimental analysis comparing door-to-antibiotic time for sepsis patients at the intervention ED after versus before care reorganization, applying differencein-differences methods to control for trends in door-to-antibiotic time unrelated to the studied intervention and multivariable regression to adjust for patient characteristics. Results The analysis included 3,230 ED sepsis patients, including 1,406 from the intervention ED. Adjusted analyses using difference-in-differences methods to control for temporal trends unrelated to the studied intervention revealed no significant change in door-to-antibiotic time after care reorganization (-7 minutes, 95% CI -20 to 6 minutes, p = 0.29). Multivariable pre/ post analyses using data only from the intervention ED overestimated the magnitude and statistical significance of outcome changes associated with ED care reorganization. Conclusions Implementation of an ED care model involving parallel multidisciplinary assessment and early team discussion of the care plan was not associated with improvements in mid- and low-acuity sepsis patients' door-to-antibiotic time after accounting for changes in the outcome unrelated to the studied intervention.