National Emergency Department Information System Research Articles

Impact of ambient temperature on respiratory disease: a case-crossover study in Seoul.

Respiratory diseases contribute to global morbidity and mortality, and temperature is a significant factor. We investigated the association between ambient temperature and emergency department (ED) visits for various respiratory diseases in Seoul, South Korea. Using data from the National Emergency Department Information System (2008-2017), we analysed 1,616,644 ED visits for respiratory diseases, categorised according to the Korean Standard Classification of Diseases 7th revision codes (J00-J99). Using a time-stratified case-crossover design and a distributed lag nonlinear model, we investigated the effect of temperature exposure on ED visits for respiratory diseases, calculating the relative risk (RR) for the maximum risk temperature (MaxRT) of both cold and hot extremes compared to the minimum risk temperature (MinRT). Cold temperatures (MaxRT: -9.0°C) resulted in a 2.68-fold increase (RR = 2.68, 95% CI = 2.26-3.14) in ED visits for total respiratory diseases, while hot temperatures (MaxRT: 29.4°C) led to a 1.26-fold increase (RR = 1.26, 95% CI = 1.11-1.42) compared to the MinRT (24.8°C). Cold temperatures increased the risk of most respiratory diseases, except interstitial lung disease, whereas hot temperatures increased ED visits for acute upper respiratory infections and influenza. Cold temperatures increased ED visits for all age groups, especially those aged 18-64 (RR = 3.54, 95% CI = 2.90-4.33), while hot temperatures significantly affected those < 18 (RR = 1.45, 95% CI = 1.27-1.66). The risk levels were similar in both males and females, regardless of hot and cold temperatures. Our findings underscore the significant impact of both cold and heat exposure on ED visits for respiratory diseases, with varying intensities and risk profiles across different population groups.

The pattern of emergency department utilization in pediatric patients who underwent interfacility transfers from the emergency department: a nationwide population-based study in South Korea, 2016-2018

Purpose: The shortage of pediatric emergency care has become a significant societal issue. This study investigated the usage pattern of emergency departments (EDs) by pediatric patients who underwent interfacility transfers (IFTs) in South Korea, focusing on cases involving single and double IFTs.Methods: This nationwide cross-sectional study included all pediatric patients (&lt; 19 years) who underwent IFTs at regional and local emergency medical centers from 2016 through 2018, using data from the National Emergency Department Information System. After excluding unidentified cases, clinical features and ED use patterns were compared between patients with single IFT, i.e., an IFT after the initial ED visit, and those with double IFT, i.e., a sequential transfer from one medical facility to another.Results: Among 20,888 pediatric cases of IFTs in the ED, 21.0% of disease cases (3,070/14,624) and 11.4% of injury cases (691/6,038) experienced double IFTs. The double-transfer group showed a lower proportion of high acuity than the single-transfer group (22.6% vs. 15.0%; P &lt; 0.001). However, median values of ED length of stay were longer in the double-transfer group, regardless of type of cases (disease: 163 minutes [single] vs. 218 minutes [double]; injury, 111 minutes vs. 172 minutes; all Ps &lt; 0.001). Guardian’s request was a substantial reason for double IFT (disease, 29.9% [919/3,070]; injury, 56.4% [390/691]).Conclusion: Double IFT is common in pediatric patients and strains medical resources, regardless of severity. The high occurrence of double IFT driven by guardians’ requests rather than medical emergencies underscores the need for improved awareness of the emergency medical system among pediatric patients’ caregivers.

Interrupting Effect of Social Distancing on Ischemic Heart Disease, Asthma, Stroke, and Suicide Attempt Patients by PM2.5 Exposure.

This study aimed to examine the interrupting effect of social distancing (SD) on emergency department (ED) patients with ischemic heart disease (IHD), stroke, asthma, and suicide attempts by PM2.5 exposure in eight Korean megacities from 2017 to 2020. The study used National Emergency Department Information System and AirKorea data. A total of 469014 patients visited EDs from 2017 to 2020. Interrupted time series analysis was employed to examine changes in the level and slope of the time series, relative risk, and confidence intervals (CIs) by PM2.5 exposure. The SD level was added to the sensitivity analysis. The interrupted time series analysis demonstrated a significant increase in the ratio of relative risk (RRR) of IHD patients in Seoul (RRR=1.004, 95% CI: 1.001, 1.006) and Busan (RRR=1.007, 95% CI: 1.002, 1.012) post-SD. Regarding stroke, only patients in Seoul exhibited a significant decrease post-SD (RRR=0.995, 95% CI: 0.991, 0.999). No significant changes were observed for asthma in any of the cities. In the case of suicide attempts, Ulsan demonstrated substantial pre-SD (RR=0.827, 95% CI: 0.732, 0.935) and post-SD (RRR=1.200, 95% CI: 1.057, 1.362) differences. While the interrupting effect of SD was not as pronounced as anticipated, this study did validate the effectiveness of SD in modifying health behaviors and minimizing avoidable visits to EDs in addition to curtailing the occurrence of infectious diseases.

Demographic characteristics of patients admitted to the emergency department for intoxication and a time series analysis during the COVID-19 period

Purpose: This study investigated the characteristics and treatment outcomes of patients who visited the emergency department due to intoxication and analyzed the impact of the coronavirus disease 2019 (COVID-19) pandemic on their visits.Methods: A retrospective study was conducted using data from the National Emergency Department Information System (NEDIS) on patients who visited the emergency department due to intoxication between January 2014 and December 2020. In total, 277,791 patients were included in the study, and their demographic and clinical data were analyzed. A model was created from 2014 to 2019 and applied to 2020 (i.e., during the COVID-19 pandemic) to conduct a time series analysis distinguishing between unexpected accidents and suicide/self-harm among patients who visited the emergency department.Results: The most common reason for visiting the emergency department was unintentional accidents (48.5%), followed by self-harm/suicide attempts (43.8%). Unexpected accident patients and self-harm/suicide patients showed statistically significant differences in terms of sex, age group, hospitalization rate, and mortality rate. The time series analysis showed a decrease in patients with unexpected accidents during the COVID-19 pandemic, but no change in patients with suicide/self-harm.Conclusion: Depending on the intentionality of the intoxication, significant differences were found in the age group, the substance of intoxication, and the mortality rate. Therefore, future analyses of patients with intoxication should be stratified according to intentionality. In addition, the time series analysis of intentional self-harm/suicide did not show a decrease in 2010 in the number of patients, whereas a decrease was found for unintentional accidents.

Ischaemic stroke in patients with diabetes requiring urgent procedures during the COVID-19 pandemic in South Korea: a retrospective, nationwide, population-based cohort study using data from the National Emergency Department Information System

ObjectivesThe COVID-19 pandemic resulted in suboptimal care for ischaemic stroke. Patients with diabetes mellitus (DM), a high-risk group for stroke, had compromised routine care during the pandemic, which increases the...

Characteristics of pediatric emergency department visits before and during the COVID-19 pandemic: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

: As of 2018, approximately 1.2 million pediatric patients visited emergency departments (EDs) in Korea, showing a steady increase. Given the distinct differences between children and adults, it is vital to examine the epidemiological characteristics of pediatric patients visiting the ED. : This study retrospectively analyzed the ED use patterns of pediatric patients <18 years old in Korea from January 1, 2018, to December 31, 2022, using data from the National Emergency Department Information System (NEDIS). : Most pediatric ED patients were boys, with an average age of 6.6±5.3 years. Patients younger than 1 year and those in critical condition had longer ED stays and more frequently required hospital admission and used the 119-ambulance service. The primary symptom was fever, and the most common discharge diagnosis was gastroenteritis. Following the declaration of the COVID-19 pandemic in 2020, ED visits decreased by 49%. Meanwhile, there was an increase in in-hospital mortality rate/age- and sex-standardized mortality rate per 100,000 ED visits, Admission and transfer rates remained similar between before and after the start of the pandemic. : Through this analysis, we identified the characteristics of pediatric patients visiting EDs in Korea. We observed a sharp decline in ED visits after the start of the COVID-19 pandemic. From there, ED visits slowly increased but remained below prepandemic levels for 3 years. This research will serve as a foundational resource for appropriately allocating and preparing pediatric ED resources.

Epidemiologic trends of patients who visited nationwide emergency departments: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

: This study analyzed trends in emergency department (ED) visits in South Korea using the National Emergency Department Information System (NEDIS) data from 2018 to 2022. : This was a retrospective observational study using data from the NEDIS database from 2018 to 2022. Age- and sex-standardized ED visits per 100,000 population, as well as age- and sex-standardized rates for mortality, admission, and transfer, were calculated. : The standardized ED visits per 100,000 population was approximately 20,000 from 2018 to 2019 and decreased to about 18,000 in 2022. The standardized mortality rate ranged from 1.4% to 1.7%. The admission rate (18.4%-19.4%) and the transfer rates (1.6%-1.8%) were similar during the study period. Approximately 5.5% of patients were triaged as Korean Triage and Acuity Scale score 1 or 2. About 91% of patients visited the ED directly and 21.7% of patients visited the ED with an ambulance. The ED length of stay was less than 6 hours in 90.3% of patients and the ED mortality rate was 0.6%. Acute gastroenteritis was the most common diagnosis. Respiratory virus symptoms, such as fever and sore throat, were also common chief complaints. : ED visits decreased during the 5-year period, while admission, transfer, and death rates remained relatively stable.

Emergency department utilization in elderly patients: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

: With general aging of the population, emergency department (ED) utilization by elderly patients is increasing. In this study, we analyzed data on ED visits of patients aged 65 years and older in Korea. : The study is a retrospective analysis of National Emergency Department Information System (NEDIS) data from 2018-2022, focusing on patients aged 65 years and older who visited EDs across Korea. ED utilization data were analyzed using Korean Triage and Acuity Scale (KTAS) scores. The patients were divided into three age groups, and common chief complaints and diagnoses were identified. Age- and sex-standardized ED visits per 100,000 population and outcomes were also analyzed. : During the study period, there was a total of 9,803,065 elderly patient ED visits. The mean patient age was 76.4±7.6 years, and 47.6% were men. The ED mortality rate and in-hospital mortality rate were 1.8% and 4.6%, respectively. The KTAS scores 1-2 group accounted for 11.0% of patients, KTAS score 3 group for 42.5%, KTAS scores 4-5 group for 37.2%, and KTAS score unknown group for 9.4%. When patients were categorized into three age groups, the oldest group exhibited the highest rates of KTAS score 1, severe illness diagnoses, and mortality. The most frequently reported chief complaint was abdominal pain, and the most common diagnosis was light headedness. When analyzing the data by year, the COVID-19 outbreak had a discernible impact on ED visits and clinical outcomes. : Over the past 5 years, ED visits for elderly patients have averaged 26,050 per 100,000 population per year, with a temporary decline during the COVID-19 pandemic and a subsequent upward trend.

Epidemiology of suicide attempts and self-harm in emergency departments: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Epidemiology of suicide attempts and self-harm in emergency departments: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Mortality and incidence rate of acute severe trauma patients in the emergency department: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Mortality and incidence rate of acute severe trauma patients in the emergency department: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Recent status of sudden cardiac arrests in emergency medical facilities: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Recent status of sudden cardiac arrests in emergency medical facilities: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Trends in traumatic brain injury-related emergency department visits in Korea: a report from the National Emergency Department Information System (NEDIS) 2018-2022.

Trends in traumatic brain injury-related emergency department visits in Korea: a report from the National Emergency Department Information System (NEDIS) 2018-2022.

Epidemiology of stroke in emergency departments: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Epidemiology of stroke in emergency departments: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Acute myocardial infarction diagnosed in emergency departments: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Acute myocardial infarction diagnosed in emergency departments: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

Incidence of overtriage and undertriage and associated factors: A cross-sectional study using a secondary data analysis.

Improving triage accuracy for accurate patient identification and appropriate resource allocation is essential. Little is known about the trend of triage accuracy, and factors associated with mistriage vary from study to study. To identify incidence and risk factors of mistriage, such as overtriage and undertriage. This is a cross-sectional study. The data came from the National Emergency Department Information System database in 2016-2020. All patients 15 years and older visiting emergency departments in Korea were assessed for eligibility, and 20,641,411 emergency patients' data were used. Multivariable logistic regressions were conducted to confirm the associated factors with overtriage and undertriage compared to expected triage. Demographic characteristics, disease-related signs and triage-related factors were independent variables. Expected triage decreased from 96.8% in 2016 to 95.7% in 2020. Overtriage (0.5%-0.7%) and undertriage (2.4%-3.3%) increased. The occupation that performed triage the most (over 85%) was nurses. Associated factors with overtriage were demographic characteristics (40-64 age group, female), disease-related signs (known disease, direct visit) and triage-related factors (regional emergency medical centre). Risk factors to undertriage were disease-related signs (systolic/diastolic blood pressure and pulse rates within normal range). While the acuity degree remained within the recommended range, the accuracy of triage decreased, and there was a gradual increase in mistriaged cases. Nurses have performed most of the triage and played a key role in expected triage. Associated factors with overtriage were demographic characteristics, disease-related signs and triage-related factors and risk factors to undertriage were disease-related signs. No patient or public contribution. Nurses should be aware of what factors are associated with mistriage and why the factors cause mistriage to improve the triage accuracy because they are responsible for the majority of the triage assessments.

Trends for syndromic surveillance of norovirus in emergency department data based on chief complaints.

This study compared the trends in norovirus cases to determine whether chief complaint-based emergency department (ED) visits data could reflect trends of norovirus in Korea. The ED visits from the National Emergency Department Information System (NEDIS) database and the weekly reported number of noroviruses from the sentinel surveillance system were collected between August 2017 and December 2020. The correlation between weekly norovirus cases and weekly ED visits considering the chief complaint and discharge diagnosis code was estimated using a three-week moving average. In total, 6,399,774 patients with chief complaints of digestive system disease visited ED. A higher correlation between reported norovirus cases and ED visit with chief complaint of vomiting and discharge diagnosis code of gastroenteritis and colitis of unspecified origin or other and unspecified gastroenteritis and colitis of infectious origin was observed (R=0.88, p<.0001). The correlation was highest for the 0-4-years age group (R=0.89, p<.0001). However, no correlation was observed between the reported norovirus cases and the number of emergency department visits with norovirus identified as a discharge diagnosis code. ED visit data considering a combination of chief complaints and discharged diagnosis code would be available for early detection of infectious disease trends.

Epidemiology and clinical characteristics of trauma in older patients transferred from long-term care hospitals to emergency departments: A nationwide retrospective study in South Korea

BackgroundSouth Korea's aging population had leg to an increased number of long-term care hospitals (LTCHs), and increased transfer of older patients to emergency departments (EDs). This study investigated the epidemiological and injury profiles of LTCH patients aged ≥65 who were transferred from LTCHs to EDs due to trauma. Method: This retrospective study conducted between January 2014 and December 2019 in South Korea utilized data from the National Emergency Department Information System. The requirement for informed consent was waived by the IRB due to the retrospective nature of the study. Patient information was anonymized prior to analysis. ResultsOf the 1,472,006 trauma cases aged ≥65, 14,469 came from LTCHs. Outcomes varied: 44.1% were discharged, 40.6% were admitted to general wards (GW), 5.9% to intensive care units (ICU), 2.4% to other hospitals, and 6.5% returned to LTCHs. ED length of stay (LOS) was longest in the death (410.28 ± 559.73 min) and GW admission (390.12 ± 621.71 min) groups. Falls were the main cause of injury (50.1%), and the most common fracture was femoral (71.6%). Femoral and shoulder/upper extremity fractures increased hospitalization risk only, whereas self-harm increased both hospitalization and mortality risk. ConclusionVisits to the ED by older patients from LTCH for trauma were avoidable in 50.6% of cases. Additionally, these patients had longer ED LOS and higher hospitalization rates than non-LTCH patients. Falls were the predominant mode of presentation, femoral fracture was the most common fracture among patients from LTCH.

An Artificial Intelligence Model for Predicting Trauma Mortality Among Emergency Department Patients in South Korea: Retrospective Cohort Study.

Within the trauma system, the emergency department (ED) is the hospital's first contact and is vital for allocating medical resources. However, there is generally limited information about patients that die in the ED. The aim of this study was to develop an artificial intelligence (AI) model to predict trauma mortality and analyze pertinent mortality factors for all patients visiting the ED. We used the Korean National Emergency Department Information System (NEDIS) data set (N=6,536,306), incorporating over 400 hospitals between 2016 and 2019. We included the International Classification of Disease 10th Revision (ICD-10) codes and chose the following input features to predict ED patient mortality: age, sex, intentionality, injury, emergent symptom, Alert/Verbal/Painful/Unresponsive (AVPU) scale, Korean Triage and Acuity Scale (KTAS), and vital signs. We compared three different feature set performances for AI input: all features (n=921), ICD-10 features (n=878), and features excluding ICD-10 codes (n=43). We devised various machine learning models with an ensemble approach via 5-fold cross-validation and compared the performance of each model with that of traditional prediction models. Lastly, we investigated explainable AI feature effects and deployed our final AI model on a public website, providing access to our mortality prediction results among patients visiting the ED. Our proposed AI model with the all-feature set achieved the highest area under the receiver operating characteristic curve (AUROC) of 0.9974 (adaptive boosting [AdaBoost], AdaBoost + light gradient boosting machine [LightGBM]: Ensemble), outperforming other state-of-the-art machine learning and traditional prediction models, including extreme gradient boosting (AUROC=0.9972), LightGBM (AUROC=0.9973), ICD-based injury severity scores (AUC=0.9328 for the inclusive model and AUROC=0.9567 for the exclusive model), and KTAS (AUROC=0.9405). In addition, our proposed AI model outperformed a cutting-edge AI model designed for in-hospital mortality prediction (AUROC=0.7675) for all ED visitors. From the AI model, we also discovered that age and unresponsiveness (coma) were the top two mortality predictors among patients visiting the ED, followed by oxygen saturation, multiple rib fractures (ICD-10 code S224), painful response (stupor, semicoma), and lumbar vertebra fracture (ICD-10 code S320). Our proposed AI model exhibits remarkable accuracy in predicting ED mortality. Including the necessity for external validation, a large nationwide data set would provide a more accurate model and minimize overfitting. We anticipate that our AI-based risk calculator tool will substantially aid health care providers, particularly regarding triage and early diagnosis for trauma patients.

Clinical support system for triage based on federated learning for the Korea triage and acuity scale

Background and aimsThis study developed a clinical support system based on federated learning to predict the need for a revised Korea Triage Acuity Scale (KTAS) to facilitate triage. MethodsThis was a retrospective study that used data from 11,952,887 patients in the Korean National Emergency Department Information System (NEDIS) from 2016 to 2018 for model development. Separate cohorts were created based on the emergency medical center level in the NEDIS: regional emergency medical center (REMC), local emergency medical center (LEMC), and local emergency medical institution (LEMI). External and temporal validation used data from emergency department (ED) of the study site from 2019 to 2021. Patient features obtained during the triage process and the initial KTAS scores were used to develop the prediction model. Federated learning was used to rectify the disparity in data quality between EDs. The patient's demographic information, vital signs in triage, mental status, arrival information, and initial KTAS were included in the input feature. Results3,626,154 patients' visits were included in the regional emergency medical center cohort; 8,278,081 patients' visits were included in the local emergency medical center cohort; and 48,652 patients’ visits were included in the local emergency medical institution cohort. The study site cohort, which is used for external and temporal validation, included 135,780 patients visits. Among the patients in the REMC and study site cohorts, KTAS level 3 patients accounted for the highest proportion at 42.4% and 45.1%, respectively, whereas in the LEMC and LEMI cohorts, KTAS level 4 patients accounted for the highest proportion. The area under the receiver operating characteristic curve for the prediction model was 0.786, 0.750, and 0.770 in the external and temporal validation. Patients with revised KTAS scores had a higher admission rate and ED mortality rate than those with unaltered KTAS scores. ConclusionsThis novel system might accurately predict the likelihood of KTAS acuity revision and support clinician-based triage.

Factors related to the frequent use of emergency department services in Korea

BackgroundFrequent Emergency Department (ED) visitors are identified by the policymakers to reduce avoidable ED visits and lessen the financial and operational burden. This study aimed to identify the factors related to the frequent use of ED services.MethodsThis nationwide, cross-sectional observational study was conducted using information obtained from the 2019 National Emergency Department Information System (NEDIS) database. Frequent ED users were defined as patients with four or more ED visits a year. We performed multiple logistic regression analyses to verify the relationship among sociodemographic characteristics, residential characteristics, clinical characteristics, and frequency of ED visits.ResultsAmong 4,063,640 selected patients, 137,608 patients visited the ED four or more times a year (total number of visits = 735,502 times), which accounted for 3.4% and 12.8% of the total number of ED users and ED visits, respectively. A high ED visit frequency was associated with male sex, age < 9 or ≥ 70 years, Medical Aid (based on the insurance type), lower number of medical institutions and beds compared with that of the national average, and conditions, such as cancer, diabetes, renal failure, and mental illness. A low ED-visit frequency was associated with residence in regions vulnerable to emergency medical care and regions with high income. The possibility of frequent ED visits was high for patients with level 5 severity (non-emergent) and those with an increased need for medical treatment, including older patients and patients with cancer or mental illness. The possibility of frequent ED visits was low for patients aged > 19 years with level 1 severity (resuscitation).ConclusionsHealth service accessibility factors, including low income and medical resource imbalance, were associated with frequent ED visits. Future large-scale prospective cohort studies are warranted to establish an efficient emergency medical system.