title: Demand on ED resources during periods of widespread influenza activity.
abstract: The purpose of this study was to investigate ED resource demand during periods of Centers for Disease Control and Prevention (CDC)-declared widespread influenza activity (WIA). An observational analysis of secondary data describing ED resource demand was performed using computerized ED patient data over a 130-week period. Measures of ED resource utilization were compared during WIA and non-WIA periods. These measures included weekly census; percentage of patients triaged as having fever, infection, or respiratory (flu index) chief complaints; admission rate, ED LOS (length of stay), total bed time (TBT), the number of patients who left the ED without being seen by a physician (LWBS), and ED saturation time. The study included 34 weeks of CDC-designated WIA occurring over 3 distinct periods. During WIA, the flu index was elevated, 23% (95% confidence interval [CI], 20-25) versus 17% (95% CI, 16-17). There was increased resource utilization during WIA periods compared with the non-WIA periods for the following parameters: admission rate (24% [95% CI, 24-25%] versus 23% [23-23%]), ED LOS admitted (296 [95% CI, 280-313] versus 271 [95% CI, 265-277]), ED LOS discharged (162 [95% CI, 156-168] versus 152 [95% CI, 150-154]), ED saturation time (1292 [95% CI, 689-1894] versus 409 [95% CI, 209-609]) and LWBS (31 [95% CI, 19-42] versus 14 [95% CI, 12-15]). Although each WIA period was marked by an initial spike in patient volume, weekly census did not increase (1365 [95% CI, 1297-1433] during WIA versus 1297 [95% CI, 1275-1320] during non-WIA). An association between WIA and greater ED resource demand was observed. A spike in census was observed at the onset of each WIA period. In addition, the flu index increased during WIA, suggesting the use of the ED as a site for syndromic surveillance of WIA onset.
authors.affiliation: Ruth and Harry Roman Emergency Department, Burns and Allen Research Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA. Paul.Silka@cshs.org
authors.forename: Paul A
authors.initials: PA
authors.lastname: Silka
authors.forename: Joel M
authors.initials: JM
authors.lastname: Geiderman
authors.forename: Joshua B
authors.initials: JB
authors.lastname: Goldberg
authors.forename: Linda Park
authors.initials: LP
authors.lastname: Kim
mesh_terms: D002487:Centers for Disease Control and Prevention, U.S.; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D006301:Health Services Needs and Demand; D006786:Hospitals, Urban; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology*; D007902:Length of Stay / Q000706:statistics & numerical data; D015141:Los Angeles / Q000453:epidemiology; D016347:Medical Records Systems, Computerized; D010343:Patient Admission / Q000706:statistics & numerical data; D012189:Retrospective Studies; D014481:United States