The Korean Triage and Acuity Scale: associations with admission, disposition, mortality and length of stay in the emergency department

Objective: The Korean Triage and Acuity Scale (KTAS) was implemented in our emergency department (ED) in May 2016 and is fully integrated into the electronic medical record (EMR) system. Our objective was to determine whether the KTAS is associated with changes in admissions to the hospital, admission disposition, inpatient mortality and length of stay (LOS). Design: Quasi-experimental, uncontrolled before-and-after study. Setting: The urban tertiary teaching hospital with 1100 beds and receives approximately annual 90 000 ED visits. Participants: 122 370 patients who visited the ED during the before-and-the after period. Interventions: ED staff were educated on the KTAS for 1 month, after which the KTAS evaluation period began. Admission, disposition, mortality and LOS were compared between the 'before' period (1 June 2015 to 30 April 2016) and the 'after' period (1 June 2016 to 30 April 2017). Main outcome measures: Admissions to the hospital, admission disposition, inpatient mortality and LOS. Results: A total of 59 220 and 63 150 patients were included in the before-and-after periods of KTAS implementation, respectively. The pattern of admission and disposition changed significantly after implementation of the KTAS. The mean LOS was 343 min (standard deviation [SD] = 432 min) during the before period, which significantly decreased to 289 min (SD = 333 min) after implementation (P < 0.001). The total mortality rate was significantly reduced after implementation of the KTAS (213 (0.36%) vs. 179 (0.28%), P = 0.020). Conclusion: Implementation of the KTAS changed admission and disposition patterns and reduced the LOS and mortality in the ED.