Changes in specialty-specific emergency department utilization before and after the 2024 resident physician walkout in South Korea

Large-scale healthcare workforce disruption may alter emergency department (ED) utilization, patient acuity, and referral patterns. We evaluated changes in ED utilization among four selected specialties before and after the 2024 resident physician walkout in South Korea. This nationwide retrospective pre–post study used data from the National Emergency Department Information System. ED visits recorded as primarily managed by plastic surgery, dermatology, ophthalmology, or otorhinolaryngology at tertiary general hospitals between March 1 and December 31, 2023 (pre-walkout), and the corresponding period in 2024 (post-walkout), were compared. Demographics, visit characteristics, Korean Triage and Acuity Scale (KTAS) level, disposition, and diagnosis distributions were analyzed. Separate multivariable logistic regression models evaluated inter-hospital transfer, high-acuity triage (KTAS levels 1–2), and hospital admission, with study period as the primary exposure. Modified Poisson regression was performed as a complementary analysis. A total of 108,848 ED visits were included, comprising 91,626 pre-walkout and 17,222 post-walkout visits, representing an 81.2% reduction in visits recorded as primarily managed by the four selected specialties. Although the proportions of KTAS level 1–2 visits, inter-hospital transfers, and hospital admissions increased from 7.1% to 14.9%, 14.2% to 23.7%, and 13.2% to 23.8%, respectively, their absolute counts decreased from 6,474 to 2,560, 12,977 to 4,090, and 12,082 to 4,092. Lower-acuity visits (KTAS levels 4–5) decreased more markedly, from 55,832 to 6,157. In adjusted analyses, among visits recorded as primarily managed by the four selected specialties, the post-walkout period was associated with higher odds of inter-hospital transfer (aOR, 1.62; 95% CI, 1.56–1.69), high-acuity triage (aOR, 1.91; 95% CI, 1.81–2.01), and hospital admission (aOR, 1.78; 95% CI, 1.71–1.85). Modified Poisson analyses showed consistent directions of association. ED visits recorded as primarily managed by the four selected specialties decreased markedly after the resident physician walkout. Within the substantially smaller post-walkout cohort, high-acuity, transferred, and admitted patients accounted for larger proportions despite decreases in their absolute numbers. These findings indicate a shift toward a relatively more acute and resource-intensive case mix, consistent with a disproportionately greater reduction in lower-acuity presentations rather than preservation of absolute time-sensitive emergency demand.