Sun Ju Kim

Background/Objectives: Emergency department (ED) attendance may change differently from subsequent hospital utilisation during healthcare disruptions. We compared two historical crisis episodes within one Korean regional emergency medical centre. Methods: Four calendar-aligned 224-day windows before and after the onset of COVID-19 and the 2024 workforce disruption were analysed using episode-by-phase interactions. Modified Poisson models used patient-and-day two-way clustered variance. Less-conditioned and initial-acuity-conditioned models were compared. Daily counts used calendar-lag autocorrelation-consistent variance. Source-data audits, full-period segmented analyses and alternative-baseline sensitivities were added. Results: The windows included 83,998 visits by 66,096 patients after source-data recoding. The ratio of relative changes was 0.73 (95% confidence interval [CI], 0.68–0.78) for daily visits, 1.28 (1.19–1.37) for transfer-in presentation and 1.44 (1.33–1.55) for acuity-conditioned ICU admission. EMS arrival increased more during COVID-19, but the corrected physiological composite showed no clear between-episode contrast. ED-origin ICU admissions/day were 9.24 before and 9.67 during the workforce episode; the primary ratio of incidence rate ratios was 1.13 (1.05–1.22), but the prior-calendar-year sensitivity included the null (1.06, 0.97–1.15). Workforce-period mortality associations differed before and after acuity conditioning, with adjusted risk ratios of 1.28 (1.10–1.49) and 1.06 (0.92–1.22), respectively. Conclusions: Attendance contracted more than ED-origin ICU admission volume during the observed workforce episode. These findings describe utilisation, not measured capacity pressure, and depend partly on baseline and adjustment choices. The contribution is a multidimensional approach to utilisation surveillance, not universal crisis-specific effects or evidence of unchanged survival.

Heat-related illnesses (HRIs) represent an increasingly critical threat to the health and operational readiness of the Republic of Korea (ROK) Armed Forces. Rising global temperatures, combined with Korea’s humid summers and intensive military training, have increased both the incidence and severity of HRIs among soldiers. This paper provides a comprehensive review of HRIs in the ROK military, beginning with an overview of their pathophysiology and classification, ranging from heat cramps to exertional heat stroke—the most severe and life-threatening form. We then examine recent epidemiological trends, which reveal over 1,200 documented cases between 2018 and 2023, with new recruits disproportionately affected. A comparative analysis across service branches indicates that Army personnel, who engage in high-intensity outdoor training, bear the greatest burden, while Navy and Air Force members face distinct occupational exposures in engine rooms and on airfields, respectively. The risk in the ROK military is striking in international comparison: odds ratios suggest that soldiers face more than 27 times the risk of HRIs compared with the civilian population, exceeding reported burdens in allied militaries such as the United States and Japan. Lessons from other nations, particularly the use of real-time surveillance, wearable technologies, and structured acclimatization programs, offer valuable models for ROK. Preventive strategies must therefore extend beyond medical management to include leadership accountability, environmental engineering, digital monitoring, and a cultural shift that promotes reporting. In an era of accelerating climate change, HRIs must be reframed not only as medical conditions but also as preventable threats to combat readiness, soldier welfare, and national security.

Background/Objectives: Initially normal serum creatine kinase (CK) activity may not exclude evolving muscle injury after a snakebite. We evaluated delayed CK elevation, clinical correlates, antivenom exposure, and hospital-day trajectories. Methods: We retrospectively analyzed 499 snakebite encounters at a tertiary hospital in South Korea. Delayed elevation was defined as serum CK ≥1000 U/L at the first or second follow-up after an initial value p < 0.001), whereas major systemic outcomes were not more frequent (2/45 vs. 15/212; p = 0.745). Among 39 encounters measured on hospital days 1–5, the median CK level peaked on day 3 and remained above 1000 U/L on day 5. Conclusions: An initially normal CK level did not exclude later elevation among retested encounters. The population incidence remained uncertain because follow-up was clinically patterned. Delayed elevation was primarily linked to local progression rather than major systemic outcomes. Selective repeat CK testing may complement serial clinical assessments when envenomation remains active.

Clinical and Experimental Emergency Medicine

Objectives: Severe trauma remains a leading cause of death in the Republic of Korea. In response, regional trauma centers were established in 2012. This study evaluated the impact of direct prehospital transport to trauma centers on in-hospital mortality among patients with severe trauma using the national trauma registry.Methods: This nationwide observational study utilized data from the Korean community-based trauma registry between 2016 and 2020. Patients with an injury severity score >15 who were directly transported from the prehospital setting were included. Variables analyzed encompassed demographics, injury mechanism, transport time, hospital level, and outcomes. The primary outcome was in-hospital mortality. Both logistic regression and decision tree models were employed.Results: A total of 24,567 patients were included. Overall mortality decreased by 5.2% during the study period. Patients transported to level 1 or 2 trauma centers had a lower mortality rate (23.6%) compared to those transported to level 3 or 4 hospitals (28.0%). The proportion of direct transports to high-level centers increased from 46.7% to 64.1% between 2016 and 2020. Despite longer transport times, patients transported to high-level institutions exhibited improved survival, particularly when transport exceeded 30 minutes, suggesting that hospital selection may be more critical than minimizing transport time.Conclusion: Direct transport to high-level trauma centers improves survival among patients with severe trauma, even when transport times are prolonged. These findings support the importance of a well-organized trauma system that emphasizes hospital capability in prehospital triage decisions.

Park E, et al. J Korean Med Sci. 2025 Nov;40:e339. https://doi.org/10.3346/jkms.2025.40.e339

Background/Objective: In patients with severe trauma, intraosseous (IO) access is an alternative when intravenous (IV) access proves challenging. However, detailed insights into its utilization patterns and effectiveness are lacking. This study aims to evaluate the use and efficacy of IO access in hemodynamically unstable patients with trauma at level-1 trauma centers in South Korea. Methods: Data from six centers over 12 months were analyzed, focusing on patients with traumatic cardiac arrest or shock. Overall, 206 patients were included in the study: 94 in the IO group and 112 in the IV group. Results: The first-attempt success rate was higher in the IO group than in the IV group (90.4% vs. 75.5%). The procedure time in the IO group was also shorter than that in the IV group. The fluid infusion rate was lower in the IO group than in the IV group; however, the use of a pressure bag with IO access significantly increased the rate, making it comparable to the IV infusion rate. Further, regarding IO access, a humeral site provided a higher infusion rate than a tibial site. Conclusions: IO access offers a viable alternative to IV access for the initial resuscitation in patients with trauma, providing advantages in terms of procedure time and first-attempt success rate. The use of a pressure bag and a humeral site for IO access afforded infusion rates comparable to those associated with IV access.

High-quality cardiopulmonary resuscitation (CPR) is the most important factor in promoting resuscitation outcomes; therefore, monitoring the quality of CPR is strongly recommended in current CPR guidelines. Recently, transesophageal echocardiography (TEE) has been proposed as a potential real-time feedback modality because physicians can obtain clear echocardiographic images without interfering with CPR. The quality of CPR would be optimized if the myocardial ejection fraction (EF) could be calculated in real-time during CPR. We conducted a study to derive a protocol to detect systole and diastole automatically and calculate EF using TEE images acquired from patients with cardiac arrest. The data were supplemented using thin-plate spline transformation to solve the problem of insufficient data. The deep learning model was constructed based on ResUNet + + , and a monogenic filtering method was applied to clarify the ventricular boundary. The performance of the model to which the monogenic filter was added and the existing model was compared. The left ventricle was segmented in the ME LAX view, and the left and right ventricles were segmented in the ME four-chamber view. In most of the results, the performance of the model to which the monogenic filter was added was high, and the difference was very small in some cases; but the performance of the existing model was high. Through this learned model, the effect of CPR can be quantitatively analyzed by segmenting the ventricle and quantitatively analyzing the degree of contraction of the ventricle during systole and diastole.

Objective Myocardial rupture is a fatal complication of acute myocardial infarction (AMI). Early diagnosis of myocardial rupture is feasible when emergency physicians (EPs) perform emergency transthoracic echocardiography (TTE). The purpose of this study was to report the echocardiographic features of myocardial rupture on emergency TTE performed by EPs in the emergency department (ED).Methods This was a retrospective and observational study involving consecutive adult patients presenting with AMI who underwent TTE performed by EPs in the ED of a single academic medical center from March 2008 to December 2019.Results Fifteen patients with myocardial rupture, including eight (53.3%) with free wall rupture (FWR), five (33.3%) with ventricular septal rupture (VSR), and two (13.3%) with FWR and VSR, were identified. Fourteen of the 15 patients (93.3%) were diagnosed on TTE performed by EPs. Diagnostic echocardiographic features were found in 100% of the patients with myocardial rupture, including pericardial effusion for FWR and a visible shunt on the interventricular septum for VSR. Additional echocardiographic features indicating myocardial rupture were thinning or aneurysmal dilatation in 10 patients (66.7%), undermined myocardium in six patients (40.0%), abnormal regional motions in six patients (40.0%), and pericardial hematoma in six patients (40.0%).Conclusion Early diagnosis of myocardial rupture after AMI is possible using echocardiographic features on emergency TTE performed by EPs.

Kim SJ, et al. Yonsei Med J. 2021 Jul;62(7):631-639. https://doi.org/10.3349/ymj.2021.62.7.631