The usefulness of lactate/albumin ratio, C-reactive protein/albumin ratio, procalcitonin/albumin ratio, SOFA, and qSOFA in predicting the prognosis of patients with sepsis who presented to EDs.

PURPOSE: Early identification of sepsis with a poor prognosis in the emergency department (ED) is crucial for prompt management and improved outcomes. This study aimed to examine the predictive value of sequential organ failure assessment (SOFA), quick SOFA (qSOFA), lactate to albumin ratio (LAR), C-reactive protein to albumin ratio (CAR), and procalcitonin to albumin ratio (PAR), obtained in the ED, as predictors for 28-day mortality in patients with sepsis and septic shock. MATERIALS AND METHODS: We included 3499 patients (aged ≥19 years) from multicenter registry of the Korean Shock Society between October 2015 and December 2019. The SOFA score, qSOFA score, and lactate level at the time of registry enrollment were used. Albumin, C-reactive protein, and procalcitonin levels were obtained from the initial laboratory results measured upon ED arrival. We evaluated the predictive accuracy for 28-day mortality using the area under the receiver operating characteristic (AUROC) curve. A multivariable logistic regression analysis of the independent predictors of 28-day mortality was performed. The SOFA score, LAR, CAR, and PAR were converted to categorical variables using Youden's index and analyzed. Adjusting for confounding factors such as age, sex, comorbidities, and infection focus, adjusted odds ratios (aOR) were calculated. RESULTS: Of the 3499 patients, 2707 (77.4%) were survivors, whereas 792 (22.6%) were non-survivors. The median age of the patients was 70 (25th-75th percentiles, 61-78), and 2042 (58.4%) were male. LAR for predicting 28-day mortality had the highest AUROC, followed by the SOFA score (0.715; 95% confidence interval (CI): 0.69-0.74 and 0.669; 95% CI: 0.65-0.69, respectively). The multivariable logistic regression analysis revealed that the aOR of LAR >1.52 was 3.75 (95% CI: 3.16-4.45), and the aOR, of SOFA score at enrollment >7.5 was 2.67 (95% CI: 2.25-3.17). CONCLUSION: The results of this study showed that LAR is a relatively strong predictor of sepsis prognosis in the ED setting, indicating its potential as a straightforward and practical prognostic factor. This finding may assist healthcare providers in the ED by providing them with tools to risk-stratify patients and predict their mortality.

Development and derivation of bacteremia prediction model in patients with hepatobiliary infection.

INTRODUCTION: Hepatobiliary infections are common in the emergency department (ED), and the mortality rate for this condition is high. A suitable bacteremia prediction model would support prompt identification of bacteremia and appropriate management of hepatobiliary infections in the ED. Therefore, we attempted to produce a bacteremia prediction model with both internal and external validation for hepatobiliary infections in the ED. METHODS: Patients with hepatobiliary infection were extracted from retrospective cohort databases of two tertiary hospitals from January 2018 to December 2019 and from January 2016 to December 2019, respectively. Independent risk factors were determined using multivariable logistic regression in a developmental cohort. We assigned a weighted value to predictive factors and developed a prediction model, which was validated both internally and externally. We assessed discrimination using the area under the receiver operating characteristics curve (AUC). RESULTS: One hospital cohort of 1568 patients was randomly divided into a developmental group of 927 patients (60%) and an internal validation group of 641 patients (40%), and 736 people from the other hospital cohort were used for external validation. Bacteremia rates were 20.5%, 18.1%, and 23.1% in the developmental, internal, and external validation cohorts, respectively. Nine significant factors were used for predicting bacteremia, including age, three vital signs, and five laboratory tests. After applying our bacteremia prediction rule to the validation cohort, 56.5% and 53.8% of the internal and external validation groups were classified as low-risk bacteremia groups (bacteremia rates: 8.6% and 13.9%, respectively). The AUCs were 0.727 (95% confidence interval [CI]: 0.686-0.767), 0.730 (95% CI: 0.679-0.781), and 0.715 (95% CI: 0.672-0.758) for the developmental, internal, and external validation cohorts, respectively. The sensitivity and specificity for internal validation/external validation was 73.2%/67.6% and 63.0%/60.2%, respectively. CONCLUSION: A bacteremia prediction model for hepatobiliary infection might be useful to predict the risk of bacteremia. It might also reduce the need for blood culture in low-risk patients.

Clinical factors predicting return emergency department visits in chemotherapy-induced febrile neutropenia patients.

BACKGROUND: Although chemotherapy-induced febrile neutropenia (FN) is the most common and life-threatening oncologic emergency, the characteristics and outcomes associated with return visits to the emergency department (ED) in these patients are uncertain. Hence, we aimed to investigate the predictive factors and clinical outcomes of chemotherapy-induced FN patients returning to the ED. METHOD: This single-center, retrospective observational study spanning 14 years included chemotherapy-induced FN patients who visited the ED and were discharged. The primary outcome was a return visit to the ED within five days. We conducted logistic regression analyses to evaluate the factors influencing ED return visit. RESULTS: This study included 1318 FN patients, 154 (12.1%) of whom revisited the ED within five days. Patients (53.3%) revisited the ED owing to persistent fever (56.5%), with no intensive care unit admission and only one mortality case who was discharged hopelessly. Multivariable analysis revealed that shock index >0.9 (odds ratio [OR]: 1.45, 95% confidence interval [CI], 1.01-2.10), thrombocytopenia (<100 × 103/uL) (OR: 1.64, 95% CI, 1.11-2.42), and lactic acid level > 2 mmol/L (OR: 1.51, 95% CI, 0.99-2.25) were associated with an increased risk of a return visit to the ED, whereas being transferred into the ED from other hospitals (OR: 0.08; 95% CI, 0.005-0.38) was associated with a decreased risk of a return visit to the ED. CONCLUSION: High shock index, lactic acid, thrombocytopenia, and ED arrival type can predict return visits to the ED in chemotherapy-induced FN patients.

Modified Cardiovascular Sequential Organ Failure Assessment Score in Sepsis: External Validation in Intensive Care Unit Patients.

BACKGROUND: There is a need to update the cardiovascular (CV) Sequential Organ Failure Assessment (SOFA) score to reflect the current practice in sepsis. We previously proposed the modified CV SOFA score from data on blood pressure, norepinephrine equivalent dose, and lactate as gathered from emergency departments. In this study, we externally validated the modified CV SOFA score in multicenter intensive care unit (ICU) patients. METHODS: A multicenter retrospective observational study was conducted on ICU patients at six hospitals in Korea. We included adult patients with sepsis who were admitted to ICUs. We compared the prognostic performance of the modified CV/total SOFA score and the original CV/total SOFA score in predicting 28-day mortality. Discrimination and calibration were evaluated using the area under the receiver operating characteristic curve (AUROC) and the calibration curve, respectively. RESULTS: We analyzed 1,015 ICU patients with sepsis. In overall patients, the 28-day mortality rate was 31.2%. The predictive validity of the modified CV SOFA (AUROC, 0.712; 95% confidence interval [CI], 0.677-0.746; P < 0.001) was significantly higher than that of the original CV SOFA (AUROC, 0.644; 95% CI, 0.611-0.677). The predictive validity of modified total SOFA score for 28-day mortality was significantly higher than that of the original total SOFA (AUROC, 0.747 vs. 0.730; 95% CI, 0.715-0.779; P = 0.002). The calibration curve of the original CV SOFA for 28-day mortality showed poor calibration. In contrast, the calibration curve of the modified CV SOFA for 28-day mortality showed good calibration. CONCLUSION: In patients with sepsis in the ICU, the modified SOFA score performed better than the original SOFA score in predicting 28-day mortality.

Modified cardiovascular SOFA score in sepsis: development and internal and external validation.

BACKGROUND: The Sepsis-3 criteria introduced the system that uses the Sequential Organ-Failure Assessment (SOFA) score to define sepsis. The cardiovascular SOFA (CV SOFA) scoring system needs modification due to the change in guideline-recommended vasopressors. In this study, we aimed to develop and to validate the modified CV SOFA score. METHODS: We developed, internally validated, and externally validated the modified CV SOFA score using the suspected infection cohort, sepsis cohort, and septic shock cohort. The primary outcome was 28-day mortality. The modified CV SOFA score system was constructed with consideration of the recently recommended use of the vasopressor norepinephrine with or without lactate level. The predictive validity of the modified SOFA score was evaluated by the discrimination for the primary outcome. Discrimination was assessed using the area under the receiver operating characteristics curve (AUC). Calibration was assessed using the calibration curve. We compared the prognostic performance of the original CV/total SOFA score and the modified CV/total SOFA score to detect mortality in patients with suspected infection, sepsis, or septic shock. RESULTS: We identified 7,393 patients in the suspected cohort, 4038 patients in the sepsis cohort, and 3,107 patients in the septic shock cohort in seven Korean emergency departments (EDs). The 28-day mortality rates were 7.9%, 21.4%, and 20.5%, respectively, in the suspected infection, sepsis, and septic shock cohorts. The model performance is higher when vasopressor and lactate were used in combination than the vasopressor only used model. The modified CV/total SOFA score was well-developed and internally and externally validated in terms of discrimination and calibration. Predictive validity of the modified CV SOFA was significantly higher than that of the original CV SOFA in the development set (0.682 vs 0.624, p < 0.001), test set (0.716 vs 0.638), and all other cohorts (0.648 vs 0.557, 0.674 vs 0.589). Calibration was modest. In the suspected infection cohort, the modified model classified more patients to sepsis (66.0 vs 62.5%) and identified more patients at risk of septic mortality than the SOFA score (92.6 vs 89.5%). CONCLUSIONS: Among ED patients with suspected infection, sepsis, and septic shock, the newly-developed modified CV/total SOFA score had higher predictive validity and identified more patients at risk of septic mortality.

Relationship between time of emergency department admission and adherence to the Surviving Sepsis Campaign bundle in patients with septic shock.

BACKGROUND: Nighttime hospital admission is often associated with increased mortality risk in various diseases. This study investigated compliance rates with the Surviving Sepsis Campaign (SSC) 3-h bundle for daytime and nighttime emergency department (ED) admissions and the clinical impact of compliance on mortality in patients with septic shock. METHODS: We conducted an observational study using data from a prospective, multicenter registry for septic shock provided by the Korean Shock Society from 11 institutions from November 2015 to December 2017. The outcome was the compliance rate with the SSC 3-h bundle according to the time of arrival in the ED. RESULTS: A total of 2049 patients were enrolled. Compared with daytime admission, nighttime admission was associated with higher compliance with the administration of antibiotics within 3 h (adjusted odds ratio (adjOR), 1.326; 95% confidence interval (95% CI), 1.088-1.617, p = 0.005) and with the complete SSC bundle (adjOR, 1.368; 95% CI, 1.115-1.678; p = 0.003), likely to result from the increased volume of all patients and sepsis patients admitted during daytime hours. The hazard ratios of the completion of SSC bundle for 28-day mortality and in-hospital mortality were 0.750 (95% CI 0.590-0.952, p = 0.018) and 0.714 (95% CI 0.564-0.904, p = 0.005), respectively. CONCLUSION: Septic shock patients admitted to the ED during the daytime exhibited lower sepsis bundle compliance than those admitted at night. Both the higher number of admitted patients and the higher patients to medical staff ratio during daytime may be factors that are responsible for lowering the compliance.

Impact of the 24-hour time target policy for emergency departments in South Korea: a mixed method study in a single medical center.

BACKGROUND: In South Korea, after the spread of the Middle East Respiratory Syndrome epidemic was aggravated by long stays in crowded emergency departments (EDs), a 24-hour target policy for EDs was introduced to prevent crowding and reduce patients' length of stay (LOS). The policy requires at least 95% of all patients to be admitted, discharged or transferred from an ED within 24 hours of arrival. This study analyzes the effects of the 24-hour target policy on ED LOS and compliance rates and describes the consequences of the policy. METHODS: A mixed-methods approach was applied to a retrospective observational study of ED visits combined with a survey of medical professionals. The primary measure was ED LOS, and the secondary measure was policy compliance rate which refers to the proportion of patient visits with a LOS shorter than 24 hours. Patient flow, quality of care, patient safety, staff workload, and staff satisfaction were also investigated through surveys. Mann-Whitney U and χ2 tests were used to compare variables before and after the introduction of the policy. RESULTS: The median ED LOS increased from 3.9 hours (interquartile range [IQR] = 2.1-7.6) to 4.5 hours (IQR = 2.5-8.5) after the policy was introduced. This was likely influenced by the average monthly number of patients, which greatly increased from 4819 (SD = 340) to 5870 (SD = 462) during the same period. The proportion of patients with ED LOS greater than 24 hours remained below5% only after 6 months of policy implementation, but the number of patients whose disposition was decided at 23 hours increased by 4.84 times. Survey results suggested that patient flow and quality of care improved slightly, while the workload of medical staff worsened. CONCLUSIONS: After implementing the 24-hour target policy, the proportion of patients whose ED LOS exceeded 24 hours decreased, even though the median ED LOS increased. However, the unintended consequences of the policy were observed such as increased medical professional workload and abrupt expulsion of patients before 24 hours.

National Surveillance of Pediatric Out-of-Hospital Cardiac Arrest in Korea: The 10-Year Trend From 2009 to 2018.

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.

Impact of Insurance Benefits and Education on Point-of-Care Ultrasound Use in a Single Emergency Department: An Interrupted Time Series Analysis.

Background and Objectives: Point-of-care ultrasound (POCUS) is a useful tool that helps clinicians properly treat patients in emergency department (ED). This study aimed to evaluate the impact of specific interventions on the use of POCUS in the ED. Materials and Methods: This retrospective study used an interrupted time series analysis to assess how interventions changed the use of POCUS in the emergency department of a tertiary medical institute in South Korea from October 2016 to February 2021. We chose two main interventions-expansion of benefit coverage of the National Health Insurance (NHI) for emergency ultrasound (EUS) and annual ultrasound educational workshops. The primary variable was the EUS rate, defined as the number of EUS scans per 1000 eligible patients per month. We compared the level and slope of EUS rates before and after interventions. Results: A total of 5188 scanned records were included. Before interventions, the EUS rate had increased gradually. After interventions, except for the first workshop, the EUS rate immediately increased significantly (p < 0.05). The difference in the EUS rate according to the expansion of the NHI was estimated to be the largest (p < 0.001). However, the change in slope significantly decreased after the third workshop during the coronavirus disease 2019 pandemic (p = 0.004). The EUS rate increased significantly in the presence of physicians participating in intensive POCUS training (p < 0.001). Conclusion: This study found that expansion of insurance coverage for EUS and ultrasound education led to a significant and immediate increase in the use of POCUS, suggesting that POCUS use can be increased by improving education and insurance benefits.

Online Learning versus Hands-On Learning of Basic Ocular Ultrasound Skills: A Randomized Controlled Non-Inferiority Trial.

Background and objectives: Ocular ultrasound is a core application of point-of-care ultrasound (POCUS) to assist physicians in promptly identifying various ocular diseases at the bedside; however, hands-on POCUS training is challenging during a pandemic. Materials and Methods: A randomized controlled non-inferiority trial was conducted in an academic emergency department from October 2020 to April 2021. Thirty-two participants were randomly assigned to one of two groups. Group H (hands-on learning group) participated individually in a hands-on session with a standardized patient for 30 min, whereas Group O (online learning group) learned training materials and video clips for 20 min. They scanned four eyeballs of two standardized patients sequentially following the ocular POCUS scan protocol. Repeated POCUS scans were performed 2 weeks later to assess skill maintenance. Both groups completed the pre- and post-surveys and knowledge tests. Two emergency medicine faculty members blindly evaluated the data and assigned a score of 0−25. The primary endpoint was the initial total score of scan quality evaluated using non-inferiority analysis (generalized estimating equation). The secondary endpoints were total scores for scan quality after 2 weeks, scan time, and knowledge test scores. Results: The least squares means of the total scores were 21.7 (0.35) for Group O and 21.3 (0.25) for Group H, and the lower bound of the 95% confidence interval (CI) was greater than the non-inferiority margin of minus 2 (95% CI: −0.48−1.17). The second scan scores were not significantly different from those of the first scan. The groups did not differ in scanning time or knowledge test results; however, Group H showed higher subjective satisfaction with the training method (p < 0.001). Conclusion: This study showed that basic online ocular ultrasound education was not inferior to hands-on education, suggesting that it could be a useful educational approach in the pandemic era.

Prognostic implication of elevated cardiac troponin I in patients visiting emergency department without diagnosis of coronary artery disease.

OBJECTIVES: Elevated cardiac troponin is not uncommon in patients visiting emergency department (ED) even without coronary artery disease, but its prognostic implication is not well understood in such patients. METHODS: In this retrospective single-center registry, we investigated clinical outcome of patients visiting ED without documented coronary artery disease. Patients were categorized according to the maximal value of Siemens ADVIA Centaur TnI-Ultra assay (TnI) within 24 h after visit. Primary endpoint was 180-day all-cause death that included cardiac and non-cardiac death. RESULTS: A total of 35,205 patients with median age 61 years and male gender 54.7% were included. Below the lowest level of detection (LOD) (≤0.006 ng/mL), between LOD and assay-specific <99th percentile (0.007-0.039 ng/mL), below median of ≥99th percentile (0.040-0.149 ng/mL), and above median of ≥99th percentile (≥0.150 ng/mL) TnI were found in 18,502 (52.6%), 11,338 (32.2%), 3,029 (8.6%), and 2,336 (6.6%) patients. In the 180-day follow-up period, 4,341 (12.3%) all-cause death including 694 (2.0%) cardiovascular death and 3,647 (10.4%) non-cardiovascular death developed. The risks of all-cause, cardiovascular, and non-cardiovascular death increased across higher TnI strata (hazard ratio [HR]=1.3 to 2.4; 2.0 to 9.3; 1.3 to 1.7; p<0.001, all). Analyses of multivariate models showed consistent results. CONCLUSIONS: In patients visiting ED, elevated TnI was associated with higher risk of 180-day cardiovascular and non-cardiovascular death. Patients with elevated TnI may need additional evaluation or careful follow-up even without primary diagnosis of coronary artery disease.

Diagnostic accuracy of lactate levels after initial fluid resuscitation as a predictor for 28 day mortality in septic shock.

PURPOSE: The aim of the study was to investigate the diagnostic accuracy of initial and post-fluid resuscitation lactate levels in predicting 28 day mortality. MATERIALS AND METHODS: We retrospectively analyzed a multi-center registry of suspected septic shock cases that was prospectively collected between October 2015 and December 2018 from 11 Emergency Departments. The primary outcome was 28 day mortality. The diagnostic performance of the initial and post-fluid resuscitation lactate levels as a predictor for 28 day mortality was assessed. RESULTS: A total of 2568 patients were included in the final analysis. The overall 28 day mortality rate was 23%. The area under the receiver operating characteristic curve (AUROC) of initial lactate for predicting 28 day mortality was 0.66 (95% CI, 0.64-0.69) and that of after fluid administration lactate was 0.70 (95% CI, 0.67-0.72), and there was a significant difference (p < 0.001). The optimal cutoff point of lactate after fluid administration was 4.4 mmol/L. Compared with this, the Sepsis-3 definition with a lactate level of 2 mmol/L or more was relatively more sensitive and less specific for predicting 28 day mortality. CONCLUSION: The post-fluid resuscitation lactate level was more accurate than the initial lactate level in predicting 28 day mortality in patients with suspected septic shock.

Hollow adrenal gland sign on dual-phase contrast-enhanced CT in critically ill patients with sepsis.

OBJECTIVE: We aimed to describe the clinical manifestations of patients with sepsis who had the hollow adrenal gland sign (HAGS) during the acute phase of resuscitation and evaluated its value in predicting in-hospital mortality. METHODS: We performed a single-center, retrospective study of patients with sepsis who visited the emergency department (ED) from November 2015 to December 2018. The patients were categorized into the positive HAGS (pHAGS) and negative HAGS (nHAGS) groups, based on its presence in initial dual-phase contrast-enhanced abdominal computed tomography (CT). The primary outcome was in-hospital mortality. A multiple logistic regression model was developed to assess variables related to in-hospital mortality. RESULTS: In all, 156 patients were included, and 36.5% (n = 57) was assigned to the pHAGS group. Both the maximal Sequential Organ Failure Assessment score within 24 h after ED arrival (10, interquartile range [IQR] 7-13 vs. 8, IQR 6-10, p < 0.01) and APACHE II score (24, IQR 20-31 vs. 20, IQR 17-25, p < 0.01) were significantly higher in the pHAGS than in the nHAGS group; the former group received significantly more interventions including vasopressors, renal replacement therapy, mechanical ventilation, and transfusions; in-hospital mortality was significantly higher in the former than in the latter group (29.8% vs. 10.1%, p < 0.01). pHAGS was an independent predictor of in-hospital mortality (adjusted odds ratio, 2.89; 95% confidence interval, 1.08-7.78; p = 0.04). CONCLUSIONS: Patients with sepsis who showed the HAGS had more severe illness than those who did not, and had an increased need for organ-supportive interventions. Presence of the HAGS was independently associated with in-hospital mortality.

Are loose-fitting powered air-purifying respirators safe during chest compression? A simulation study.

BACKGROUND: The application of appropriate personal protective equipment for respiratory protection to health care workers is a cornerstone for providing safe healthcare in emergency departments. We investigated the protective effect and usefulness of loose-fitting powered air-purifying respirators (PAPRs) during chest compression. METHODS: This was a single-center simulation study performed from May 2019 to July 2019 in a tertiary hospital. We measured the concentrations of ambient aerosol and particles inside the loose-fitting PAPR during chest compression, and this ratio was set as the simulated workplace protecting factor (SWPF). According to the National Institute for Occupational Safety and Health regulations, the assigned protection factor (APF) of loose-fitting PAPRs is 25. Thus, the loose-fitting PAPRs were assumed to have a protective effect when the SWPF were ≥ 250 (APF × 10). We measured the SWPF of PAPR in real time during chest compression and also investigated the problems encountered during its use. RESULTS: Ninety-one participants (median age 29 [interquartile range (IQR): 26-32] years; 74% female) completed the simulation. None of the participants failed with SWPF below 250 during three sessions of chest compression. The median (IQR) values of SWPF at three cycles were 17,063 (10,145-26,373), 15,683 (9477-32,394), and 16,960 (7695-27,279). There was no disconnection of equipment or mechanical failures during chest compression. In addition, most participants (83%) replied that they rarely or never experienced difficulty in verbal communication and felt that the loose-fitting PAPR was comfortable. CONCLUSIONS: The loose-fitting PAPRs provided sufficient respiratory protection without disturbances during chest compression.

Association between wide QRS pulseless electrical activity and hyperkalemia in cardiac arrest patients.

AIM: We evaluated the relationship between hyperkalemia and wide QRS complex in patients with pulseless electrical activity (PEA) cardiac arrest. METHODS: This was a single-center, retrospective observational study of patients over the age of 18 treated for cardiac arrest at a tertiary referral hospital whose initial electrocardiogram rhythm was PEA from February 2010 to December 2019. Wide QRS PEA was defined as a QRS interval of 120 ms or more. Hyperkalemia was defined as serum potassium level > 5.5 mmol/L. The primary outcome was hyperkalemia. Multivariable logistic regression analysis was used to evaluate the relationship between wide QRS and hyperkalemia. RESULTS: Among 617 patients, we analyzed 111 episodes in the wide QRS group and 506 episodes in the narrow QRS group. The potassium level in the wide QRS group was significantly higher than in the narrow QRS group (5.4 mmol/L, IQR 4.4-6.7 vs. 4.6 mmol/L, IQR 4.0-5.6, P < 0.001). Among all patients, 49.6% (n = 55/111) in the wide QRS group had hyperkalemia, which was significantly higher than the 26.7% (n = 135/506) in the narrow QRS group (P < 0.001). In multivariable logistic regression analysis, wide QRS PEA was significantly associated with hyperkalemia (odds ratio = 2.86, 95% confidence interval: 1.80-4.53, P < 0.001). CONCLUSIONS: Wide QRS PEA as an initial cardiac rhythm was significantly associated with hyperkalemia in cardiac arrest patients.

Developing a Time-Adaptive Prediction Model for Out-of-Hospital Cardiac Arrest: Nationwide Cohort Study in Korea.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is a serious public health issue, and predicting the prognosis of OHCA patients can assist clinicians in making decisions about the treatment of patients, use of hospital resources, or termination of resuscitation. OBJECTIVE: This study aimed to develop a time-adaptive conditional prediction model (TACOM) to predict clinical outcomes every minute. METHODS: We performed a retrospective observational study using data from the Korea OHCA Registry in South Korea. In this study, we excluded patients with trauma, those who experienced return of spontaneous circulation before arriving in the emergency department (ED), and those who did not receive cardiopulmonary resuscitation (CPR) in the ED. We selected patients who received CPR in the ED. To develop the time-adaptive prediction model, we organized the training data set as ongoing CPR patients by the minute. A total of 49,669 patients were divided into 39,602 subjects for training and 10,067 subjects for validation. We compared random forest, LightGBM, and artificial neural networks as the prediction model methods. Model performance was quantified using the prediction probability of the model, area under the receiver operating characteristic curve (AUROC), and area under the precision recall curve. RESULTS: Among the three algorithms, LightGBM showed the best performance. From 0 to 30 min, the AUROC of the TACOM for predicting good neurological outcomes ranged from 0.910 (95% CI 0.910-0.911) to 0.869 (95% CI 0.865-0.871), whereas that for survival to hospital discharge ranged from 0.800 (95% CI 0.797-0.800) to 0.734 (95% CI 0.736-0.740). The prediction probability of the TACOM showed similar flow with cohort data based on a comparison with the conventional model's prediction probability. CONCLUSIONS: The TACOM predicted the clinical outcome of OHCA patients per minute. This model for predicting patient outcomes by the minute can assist clinicians in making rational decisions for OHCA patients.

The Use of Point-of-care Ultrasound in Emergency Medical Centers in Korea: a National Cross-sectional Survey.

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, education-related 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.

Respiratory Protection Effect of Ear-loop-type KF94 Masks according to the Wearing Method in COVID-19 Pandemic: a Randomized, Open-label Study.

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 ear-loop-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. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04794556.

Hypochloraemia is associated with 28-day mortality in patients with septic shock: a retrospective analysis of a multicentre prospective registry.

OBJECTIVES: Hyperchloraemia is associated with poor clinical outcomes in sepsis patients; however, this association is not well studied for hypochloraemia. We investigated the prevalence of chloride imbalance and the association between hypochloraemia and 28-day mortality in ED patients with septic shock. METHODS: A retrospective analysis of data from 11 multicentre EDs in the Republic of Korea prospectively collected from October 2015 to April 2018 was performed. Initial chloride levels were categorised as hypochloraemia, normochloraemia and hyperchloraemia, according to sodium chloride difference adjusted criteria. The primary outcome was 28-day mortality. A multivariate logistic regression model adjusting for age, sex, comorbidities, acid-base state, sepsis-related organ failure assessment (SOFA) score, lactate and albumin level was used to test the association between the three chloride categories and 28-day mortality. RESULTS: Among 2037 enrolled patients, 394 (19.3%), 1582 (77.7%) and 61 (3.0%) patients had hypochloraemia, normochloraemia and hyperchloraemia, respectively. The unadjusted 28-day mortality rate in patients with hypochloraemia was 27.4% (95% CI, 23.1% to 32.1%), which was higher than in patients with normochloraemia (19.7%; 95% CI, 17.8% to 21.8%). Hypochloraemia was associated with an increase in the risk of 28-day mortality (adjusted OR (aOR), 1.36, 95% CI, 1.00 to 1.83) after adjusting for confounders. However, hyperchloraemia was not associated with 28-day mortality (aOR 1.35, 95% CI, 0.82 to 2.24). CONCLUSION: Hypochloraemia was more frequently observed than hyperchloraemia in ED patients with septic shock and it was associated with 28-day mortality.

Effectiveness of Smartwatch Guidance for High-Quality Infant Cardiopulmonary Resuscitation: A Simulation Study.

Background and objectives: As in adults, the survival rates and neurological outcomes after infant Cardiopulmonary resuscitation (CPR) are closely related to the quality of resuscitation. This study aimed to demonstrate that using a smartwatch as a haptic feedback device increases the quality of infant CPR performed by medical professionals. Materials and methods: We designed a prospective, randomized, case-crossover simulation study. The participants (n = 36) were randomly allocated to two groups: control first group and smartwatch first group. Each CPR session consisted of 2 min of chest compressions (CCs) using the two-finger technique (TFT), 2 min of rest, and 2 min of CCs using the two-thumb encircling hands technique (TTHT). Results: The primary outcome was the variation in the "proportion of optimal chest compression duration" and "compression rate" between the smartwatch-assisted and non-smartwatch-assisted groups. The secondary outcome was the variation in the "compression depth" between two groups. The proportion of optimal CC duration was significantly higher in the smartwatch-assisted group than in the non-smartwatch-assisted group. The absolute difference from 220 was much smaller in the smartwatch-assisted group (218.02) than in the non-smartwatch-assisted group (226.59) (p-Value = 0.018). Conclusion: This study demonstrated the haptic feedback system using a smartwatch improves the quality of infant CPR by maintaining proper speed and depth regardless of the compression method used.