Impact of system shocks on pediatric prehospital time performance: a nationwide EMS registry study from South Korea

Background Health system crises, such as pandemics and workforce disruptions, can compromise emergency medical services capacity and time performance, and pediatric patients may be particularly vulnerable to these system-level disruptions. We assessed how the COVID-19 pandemic and the 2024 workforce crisis were associated with pediatric prehospital time performance and whether crisis-related changes differed between pediatric and adult transports. Methods We conducted a retrospective observational study using nationwide ambulance transport records from South Korea’s National Fire Agency (2019–2024). Pediatric patients (< 18 years) transported between March and December of each year were included; adult transports (≥ 18 years) served as a comparator. Prespecified exposure periods were the COVID-19 pandemic (March 2020–April 2023) and the workforce crisis (March–December 2024). Outcomes were response, scene, transport, and total prehospital time intervals. We performed descriptive comparisons, interrupted time-series regression of monthly mean scene time to estimate level and trend changes at crisis onset, and difference-in-differences models to compare pediatric versus adult changes with covariate adjustment. Results A total of 636,495 pediatric transports were analyzed. After COVID-19 onset, all prehospital time intervals increased, peaked in 2021–2022, and improved in 2023. During the 2024 workforce crisis, total prehospital time increased again, driven predominantly by a subsequent increase in scene time, while other components showed less consistent worsening. This scene-time–dominant pattern was consistent across major pediatric chief complaint categories. In interrupted time-series analysis, COVID-19 onset was associated with an immediate increase in monthly mean scene time (1.88 minutes; 95% confidence interval 0.57–3.18), with no significant slope change thereafter. At the onset of the workforce crisis, no significant level or slope change in scene time was detected. In difference-in-differences analyses, scene time prolongation during both crises was similar in pediatric and adult transports. Conclusions Both crises were associated with prolonged pediatric prehospital times, largely driven by increased scene time. Similar pediatric–adult changes suggest system-wide strain affecting the interface between ambulance services and receiving hospitals, supporting crisis-responsive planning and routine monitoring of pediatric prehospital time performance. Trial registration: Not applicable.