title: Evaluating the effect of emergency department crowding on triage destination.
abstract: BACKGROUND
  Emergency Department (ED) crowding has been studied for the last 20 years, yet many questions remain about its impact on patient care. In this study, we aimed to determine if ED crowding influenced patient triage destination and intensity of investigation, as well as rates of unscheduled returns to the ED. We focused on patients presenting with chest pain or shortness of breath, triaged as high acuity, and who were subsequently discharged home.
  
  
  METHODS
  This pilot study was a health records review of 500 patients presenting to two urban tertiary care EDs with chest pain or shortness of breath, triaged as high acuity and subsequently discharged home. Data extracted included triage time, date, treatment area, time to physician initial assessment, investigations ordered, disposition, and return ED visits within 14 days. We defined ED crowding as ED occupancy greater than 1.5. Data were analyzed using descriptive statistics and the χ(2) and Fisher exact tests.
  
  
  RESULTS
  Over half of the patients, 260/500 (52.0%) presented during conditions of ED crowding. More patients were triaged to the non-monitored area of the ED during ED crowding (65/260 (25.0%) vs. 39/240 (16.3%) when not crowded, P = 0.02). During ED crowding, mean time to physician initial assessment was 132.0 minutes in the non-monitored area vs. 99.1 minutes in the monitored area, P <0.0001. When the ED was not crowded, mean time to physician initial assessment was 122.3 minutes in the non-monitored area vs. 67 minutes in the monitored area, P = 0.0003. Patients did not return to the ED more often when triaged during ED crowding: 24/260 (9.3%) vs. 29/240 (12.1%) when ED was not crowded (P = 0.31). Overall, when triaged to the non-monitored area of the ED, 44/396 (11.1%) patients returned, whereas in the monitored area 9/104 (8.7%) patients returned, P = 0.46.
  
  
  CONCLUSIONS
  ED crowding conditions appeared to influence triage destination in our ED leading to longer wait times for high acuity patients. This did not appear to lead to higher rates of return ED visits amongst discharged patients in this cohort. Further research is needed to determine whether these delays lead to adverse patient outcomes.
authors.affiliation: Department of Emergency Medicine, University of Ottawa, 1053 Carling Avenue, Ottawa, ON K1Y 4E9, Canada.
authors.forename: Erin
authors.initials: E
authors.lastname: O'Connor
authors.affiliation: Department of Emergency Medicine, University of Ottawa, 1053 Carling Avenue, Ottawa, ON K1Y 4E9, Canada.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Gatien
authors.affiliation: Department of Emergency Medicine, University of Ottawa, 1053 Carling Avenue, Ottawa, ON K1Y 4E9, Canada.
authors.forename: Cindy
authors.initials: C
authors.lastname: Weir
authors.affiliation: Department of Emergency Medicine, University of Ottawa, 1053 Carling Avenue, Ottawa, ON K1Y 4E9, Canada ; Clinical Epidemiology Program, Ottawa Hospital Research Institute, The Ottawa Hospital, Civic Campus, Rm F658, 1053 Carling Ave., Ottawa, ON K1Y 4E9, Canada.
authors.forename: Lisa
authors.initials: L
authors.lastname: Calder
keywords: Emergency Department crowding; Emergency Department occupancy; High acuity; Overcrowding; Triage