This study compared key health indicators of poor, older urban adults attending a free clinic with those of the general older population, using data from the 2023 Korea National Health and Nutrition Examination Survey (KNHANES). Methods: This cross-sectional comparative study included 60 adults aged ≥60 years who attended the Raphael Nanum Homeless Clinic in Seoul. Participants completed a questionnaire, underwent anthropometric assessment, and provided fasting blood samples for measurement of total cholesterol, low density lipoprotein (LDL)-cholesterol, and triglycerides (TG). Obesity, current smoking, monthly alcohol use, poor self-rated health, and strength exercise (≥ 2 days/week) were defined according to 2023 KNHANES criteria and compared with age-matched 2023 KNHANES estimates for adults aged ≥ 60 years using independent t-tests and two-proportion z-tests. Results: Participants were predominantly men (80.0%) with a mean age of 79.9 years; 70.0% reported no regular income, and 46.7% rated their health as poor. Compared with their 2023 KNHANES counterparts, the clinic group had a higher prevalence of obesity (50.0% vs. 35.0%), particularly among men, and a more atherogenic lipid profile characterized by higher LDL-cholesterol despite similar total cholesterol levels and lower TG. The prevalence of current smoking (3.3% vs. 10.6%) and monthly alcohol use (31.7% vs. 53.0%) was significantly lower, whereas participation in strength exercise was low in both groups, with no significant differences observed. Conclusion: Poor, older urban adults exhibited multidimensional health disparities, including obesity, adverse lipid profiles, and markedly poorer self-rated health, despite lower levels of smoking and alcohol consumption. Community-based interventions targeting nutrition, physical activity, and chronic disease management are needed to reduce health inequalities in this vulnerable population.

FLASH radiotherapy (FLASH RT) is a technique to deliver ultra-high dose rate in a fraction of a second. Evidence from experimental animal models suggest that FLASH RT spares various normal tissues including the lung, gastrointestinal track, and brain from radiation-induced toxicity (a phenomenon known as FLASH effect), which is otherwise commonly observed with conventional dose rate RT. However, it is not simply the ultra-high dose rate alone that brings the FLASH effect. Multiple parameters such as instantaneous dose rate, pulse size, pulse repetition frequency, and the total duration of exposure all need to be carefully optimized simultaneously. Furthermore it is critical to validate FLASH effects in an in vivo experimental model system. The exact molecular mechanism responsible for this FLASH effect is not yet understood although a number of hypotheses have been proposed including oxygen depletion and less reactive oxygen species (ROS) production by FLASH RT, and enhanced ability of normal tissues to handle ROS and labile iron pool compared to tumors. In this review, we briefly overview the process of ionization event and history of radiotherapy and fractionation of ionizing radiation. We also highlight some of the latest FLASH RT reviews and results with a special interest to neurocognitive protection in rodent model with whole brain irradiation. Lastly we discuss some of the issues remain to be answered with FLASH RT including undefined molecular mechanism, lack of standardized parameters, low penetration depth for electron beam, and tumor hypoxia still being a major hurdle for local control. Nevertheless, researchers are close to having all answers to the issues that we have raised, hence we believe that advancement of FLASH RT will be made more quickly than one can anticipate.

Background: This study reports trends in pediatric out-of-hospital cardiac arrest (OHCA) and factors affecting clinical outcomes by age group. Methods: We identified 4,561 OHCA patients younger than 18 years between January 2009 and December 2018 in the Korean OHCA Registry. The patients were divided into four groups: group 1 (1 year or younger), group 2 (1 to 5 years), group 3 (6 to 12 years), and group 4 (13 to 17 years). The primary outcome was survival to hospital discharge, and the secondary outcomes were return of spontaneous circulation (ROSC) at the emergency department (ED) and good neurological status at discharge. Multivariate logistic analyses were performed. Results: The incidence rate of pediatric OHCA in group 1 increased from 45.57 to 60.89 per 100,000 person-years, while that of the overall population decreased over the 10 years. The rates of ROSC at the ED, survival to hospital discharge, and good neurologic outcome were highest in group 4 (37.9%, 9.7%, 4.9%, respectively) and lowest in group 1 (28.3%, 7.1%, 3.2%). The positive factors for survival to discharge were event location of a public/commercial building or place of recreation, type of first responder, prehospital delivery of automated external defibrillator shock, initial shockable rhythm at the ED. The factors affecting survival outcomes differed by age group. Conclusion This study reports comprehensive trends in pediatric OHCA in the Republic of Korea. Our findings imply that preventive methods for the targeted population should be customized by age group.

Objective: Coronavirus disease 2019 (COVID-19) has notably altered the emergency department isolation protocol, imposing stricter requirements on probable infectious disease patients that enter the department. This has caused adverse effects, such as an increased rate of leave without being seen (LWBS). This study describes the effect of fever/respiratory symptoms as the main cause of isolation regarding LWBS after the COVID-19 pandemic. Methods: We retrospectively analyzed emergency department visits before (March to July 2019) and after (March to July 2020) the COVID-19 pandemic. Patients were grouped based on existing fever or respiratory symptoms, with the LWBS rate as the primary outcome. Logistic regression analysis was used to identify the risk factors of LWBS. Logistic regression was performed using interaction terminology (fever/respiratory symptom patient [FRP] × post–COVID-19) to determine the interaction between patients with FRPs and the COVID-19 pandemic period. Results: A total of 60,290 patients were included (34,492 in the pre–COVID-19, and 25,298 in the post–COVID-19 group). The proportion of FRPs decreased significantly after the pandemic (P < 0.001), while the LWBS rate in FRPs significantly increased from 2.8% to 19.2% (P < 0.001). Both FRPs (odds ratio, 1.76; 95% confidence interval, 1.59–1.84 (P < 0.001) and the COVID-19 period (odds ratio, 2.29; 95% confidence interval, 2.15–2.44; P < 0.001) were significantly associated with increased LWBS. Additionally, there was a significant interaction between the incidence of LWBS in FRPs and the COVID-19 pandemic period (P < 0.001). Conclusion The LWBS rate has increased in FRPs after the COVID-19 pandemic; additionally, the effect observed was disproportionate compared with that of nonfever/respiratory symptom patients.

Objectives: This study introduced a novel Automatic Needle Destroyer (AND) to an emergency department (ED) and assessed its effect on healthcare providers’ work. Methods: Between August and September 2019, in the ED of a tertiary hospital in Seoul, we conducted a mixed-methods study to evaluate the efficiency, safety, and usability of the AND using video analysis, surveys, and in-depth interviews, wherein participants described the advantages and disadvantages of the AND. Results: Compared to the existing method, introducing the AND significantly reduced the operating time from 2.32 ± 1.14 seconds to 1.77 ± 3.71 seconds (p < 0.001). The normal operation rate was 90.6%. The rate of needle-stick injuries (NSIs) and the mean system usability scale (SUS) showed no significant differences. The in-depth interviews indicated that the disadvantages of the AND were mostly operational. The advantages were related to profit, reduced direct contact with hazardous waste, and behavioral changes, such as not having to recap syringes. Conclusions We introduced the AND to an ED environment, where NSIs occur frequently and many syringes are used, to evaluate its effect on providers’ work. The AND reduced the time for needle disposal, but the normal operation rate was low. No significant differences were found in the SUS score or the rate of NSIs. Although there are some restrictions on introducing the AND immediately, this study’s results showed its potential usefulness. Efforts to improve the operation of the device and a longer study period are needed to fully achieve safety and efficiency.

Background: Ear-loop-type Korean Filter 94 masks (KF94 masks, equivalent to the N95 and FFP2) are broadly used in health care settings in Korea for the coronavirus disease 2019 pandemic. Methods: A prospective randomized open-label study was designed to identify differences in the fitting performance between mask wearing methods in three different types of KF94 mask with ear loops between January to March 2021. General-fitting involved wearing an earloop-type KF94 mask, and tight-fitting involved wearing a mask aided by a clip connecting the ear loops. Each of the 30 participants wore three types of masks according to a randomly assigned order in both methods and performed a total of six quantitative fit tests (QNFTs) according to the occupational safety and health administration protocol. Results: All fit factors (FFs) measured by the QNFT were significantly higher for tight-fitting method with the clip in all KF94 masks (P < 0.001). However, the total FFs were very low, with a median (interquartile range) of 6 (3–23) and 29 (9–116) for general-fitting and tight-fitting, respectively. When wearing tightly, the horizontal 3-fold type mask with adjustable ear-loop length had the highest FF, with a median of 125, and the QNFT pass rate (FF ≥ 100) increased significantly from 4 (13%) to 18 (60%). Conclusion Even with sufficient filter efficiency, ear-loop-type-KF94 masks do not provide adequate protection. However, in relatively low-risk environments, wearing a face-seal adjustable KF94 mask and tight wearing with a clip can improve respiratory protection for healthcare workers.

Background: Point-of-care ultrasound (POCUS) is an essential tool in emergency medicine (EM). We aimed to investigate the current status and perception of POCUS use in emergency medical centers in Korea. Methods: A cross-sectional, nationwide survey was conducted using a mobile survey of physicians at emergency medical centers in Korea. The first message was sent on November 27, 2020, and the second message was sent on December 3, 2020 to the non-responders.The questionnaire comprised 6 categories and 24 questionnaires on demographics, current practice, education, perception, and barriers to the use of POCUS. Results: A total of 467 physicians participated in the survey (a response rate of 32% among 1,458 target physicians), of which 43% were residents and 57% were EM specialists. Most of the respondents (96%) answered that they use POCUS, of which 89% reported using it at least once a week. The most frequently used types of POCUS were focused assessment with sonography for trauma (68%) and echocardiography (66%). Musculoskeletal, male genital, and pediatric scans were rarely performed tests but ranked as of the scans physicians most wanted to learn. About 73% of the respondents received ultrasound education, and 41% received ultrasound education at their own institutions. Nevertheless, educationrelated barriers are still the biggest deterrent to POCUS use (60%). In addition, multivariate multinomial logistic regression analysis revealed that the greater the number of ultrasound devices and the total number of physicians in the emergency center, the more likely they were to use POCUS every day. Conclusion This study found that most physicians currently working in emergency medical centers in Korea more frequently perform various types of ultrasound scans compared to those 10 years prior. To further promote the use of POCUS, it is important to have an appropriate number of ultrasound devices and physicians in the emergency center along with systematic POCUS education.