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Emergency department visits by patients with an internal medicine specialist: understanding the role of specialists in reducing ED crowding
Abstract
As emergency department (ED) crowding continues to worsen, many visits are at academic referral hospitals. As a result, engaging specialty services will be essential to decompressing the ED. To do this, it will be important to understand which specialties to focus interventions on for the greatest impact. To characterize the ED utilization of non-surgical adult patients with an ambulatory specialist who were seen and discharged from the ED. Retrospective cohort study of all consecutive patients currently under the care from a specialist presenting to an urban, university affiliated hospital between 01 January 2015 and 31 December 2016. The identification of ED visits attributable to specialists was based on the primary diagnosis of ED visits and the frequency of visit with specialists within a given timeframe. Only patients who were discharged directly from the ED were included in the analysis. There were 29,853 ED visits by patients currently under the care of a specialist during the study period. 17.76% of these visits were related to the medical specialty of the specialist. Of these visits, 41.73% occurred during office hours, and 24.81% occurred during weekends. The specialties with the largest proportion of ED visits related to their specialty was cardiology, gastroenterology, and pulmonary, respectively. Nearly 18% of all patients that have a specialist and are treated and discharged from the ED present with a diagnosis related to their specialist’s practice. This may indicate that there is a role for specialty service to play in decreasing some ED utilization that may be appropriate for the out-patient clinical setting. By focusing attention on specific specialties and interventions targeted during office hours, there may be an opportunity to decrease ED utilization.
... 13,15 One strategy to identify patients most in need of support, and ultimately reduce the number of patients presenting to the ED, may be the use of targeted and actionable feedback to outpatient specialist clinicians regarding ED use by their patients. 7,16,17 The reports showed how each specialist's ED use rate differs from those colleagues in their practice group and were thus called "ED Use Variation" reports. Such reports were distributed to divisional leadership and to individual physicians. ...
... It may provide the starting point for an expanded concept of patient care which relies on telemedicine and involves multiple specialisms. The home treatment of acute deep vein thrombosis and pulmonary embolism [20,21] has proved effective in optimizing the overall use of resources and enhance patients' quality of life and engagement [22][23][24]. A similar transition has been observed in the field of hemophilia and other chronic bleeding disorders, with increasing interactions between central hubs and multiple specialists at different geographic locations, often achieved via telemedicine and videoconferencing [25]. ...
Oral anticoagulation is the mainstay therapy for primary and secondary prevention of thromboembolic events in patients with venous thromboembolism (VTE) and atrial fibrillation. After the introduction of direct oral anticoagulants (DOAC), the prevalence of anticoagulated patients in the general population progressively increased. This trend will likely continue because of novel indications for anticoagulant treatment, e.g., stable atherosclerotic vascular disease, and more accurate risk stratification of patients.
In light of their efficacy and safety profile, and the ease of use in fixed-dosage regimens, DOAC are overtaking INR-adjusted vitamin-K antagonist (VKA) therapy in several countries. However, patients with contraindications to DOAC will still receive VKA. Therefore, the maintenance of structured plans for VKA monitoring remains essential. In this perspective, anticoagulation clinics, which were first created in The Netherlands and Italy primarily for VKA monitoring and dosing, must be reimagined.
The ecologic study published in this issue of Internal and Emergency Medicine by Tosetto and colleagues is somehow a summary of the Italian experience with anticoagulation clinics interfacing with nursing homes, peripheral hospitals, and general practitioners. At the same time, it may represent a first step towards novel concepts of internal and vascular (tele) medicine. In their study, the authors compare the characteristics of anticoagulant use and outcome of more than 14,000 patients from two Italian provinces. These two cohorts were managed—the main novelty of the study—in the setting of two different care delivery models: (1) a comprehensive management model based on decentralized community health units heavily relying on telemedicine (here referred to as `comprehensive decentralized model’) and (2) a `usual care model’ pivoting on a single second-level center. These two models were embedded in otherwise similar healthcare settings.
The most striking results are that in the comprehensive decentralized model, as compared with the usual care model: (1) a broader use of anticoagulation (age-standardized prevalence 1.5% vs. 1.0%) was observed, as well as (2) lower annualized rates of thromboembolic complications during VKA therapy (0.36% person-years vs. 0.89% person-years, respectively), particularly among the elderly (0.22% person-years vs. 1.38% person-years). As indirect as this evidence is, one may cautiously conclude that comprehensive management models improve clinical outcomes by contributing not only to better anticoagulant control in VKA-anticoagulated patients, as previously showed, but also to better selection of candidates to anticoagulation. These results are reassuringly in line with those of the prospective, observational, multicenter START Register, which reported major improvements over the last 20 years in the care of VKA-treated patients managed by centers of the Italian Federation of anticoagulation clinics (FCSA). [...]
... Specialty-related ED visits during all hours.based on the primary discharge diagnosis from the ED and grouped based on the Clinical Classifications Software (CCS) for International Classification of Diseases (ICD), 9th Revision[4,7,11]. ...
Objective:
There have been various interventions to reduce ED utilization. Little is known about the sustainability of outcomes of interventions to reduce ED overcrowding. We sought to investigate whether the outcomes from one of successful interventions to reduce ED utilization, specialist physician level reporting were sustained over time and how this practice change was sustained over time.
Method:
This study is a longitudinal analysis of the pre and post intervention ED utilization data collected on ED pediatric patients who were followed by pediatric gastroenterologists in an urban, academic hospital. The primary outcome was the mean rate of ED visits per 1000 office visits from January, 2013 to June, 2017 using a u control chart with three sigma limits.
Results:
There were continuous leadership's support, physicians' engagement and communications among different members involved in the intervention. The rate of gastrointestinal (GI)-related ED visits after an intervention decreased by 54% from 4.89 to 2.23 during all hours and by 59% from 2.19 to 0.91 during office hours.
Discussion:
Physician-level reporting reduced ED utilization over a four year period. The outcomes could be sustained over time with sustained leadership and physicians' engagement.
Background
Clinical assessment of patients with mild traumatic brain injury (mTBI) is challenging and overuse of head CT in the ED is a major problem. Several studies have attempted to reduce unnecessary head CTs following a mTBI by identifying new tools aiming to predict intracranial bleeding. Higher levels of S100B protein have been associated with intracranial haemorrhage following a mTBI in previous literature. The main objective of this study is to assess whether plasma S100B protein level is associated with clinically significant brain injury and could be used to reduce the number of head CT post-mTBI.
Methods
Study design: secondary analysis of a prospective multicentre cohort study conducted between 2013 and 2016 in five Canadian EDs. Inclusion criteria: non-hospitalised patients with mTBI with a GCS score of 13–15 in the ED and a blood sample drawn within 24 hours after the injury. Data collected: sociodemographic and clinical data were collected in the ED. S100B protein was analysed using ELISA. All CT scans were reviewed by a radiologist blinded to the biomarker results. Main outcome: the presence of clinically important brain injury.
Results
476 patients were included. Mean age was 41±18 years old and 150 (31.5%) were women. Twenty-four (5.0%) patients had a clinically significant intracranial haemorrhage. Thirteen patients (2.7%) presented a non-clinically significant brain injury. A total of 37 (7.8%) brain injured patients were included in our study. S100B median value (Q1–Q3) was: 0.043 µg/L (0.008–0.080) for patients with clinically important brain injury versus 0.039 µg/L (0.023–0.059) for patients without clinically important brain injury. Sensitivity and specificity of the S100B protein level, if used alone to detect clinically important brain injury, were 16.7% (95% CI 4.7% to 37.4%) and 88.5% (95% CI 85.2% to 91.3%), respectively.
Conclusion
Plasma S100B protein level was not associated with clinically significant intracranial lesion in patients with mTBI.
Background
Much work on reducing ED utilization has focused on primary care practices, but few studies have examined ED visits from patients followed by specialists, especially when the ED visit is related to the specialist’s clinical practice.
Objective
To determine the proportion and characteristics of patients that utilized the ED for specialty-related diagnosis.
Methods
Retrospective, population-based, cohort study was conducted using information from electronic health records and billing database between January 2016 and December 2016. Patients who had seen a specialist during the last five years from the index ED visit date were included. The identification of ED visits attributable to specialists was based on the primary diagnosis of ED visits and the frequency of visit with specialists within a given timeframe.
Results
Approximately 28% of ED visits analyzed were attributable to specialists. ED visits attributed specialists were represented by older patients and occurred more during working hours and early days of week. The most common diagnoses related to ED visits attributed to specialists were Circulatory, Musculoskeletal, Skin, Breast and Mental. Multiple departments, subdivisions and specialists were involved with each ED visit. The number of specialists following the patients who visited the ED ranged from one to six and the number of departments/subdivisions ranged from one to four. Patients that used the ED often were more likely to belong to departments (OR = 1.53) and specialists (OR = 1.18) associated with high ED utilization patterns.
Conclusion
Patients coming to the ED with specialty-related complaints are unique and require full engagement of the specialist and the specialty group. This study offers a new view of connections patients have with their specialists and engaging specialists both at department level and individual specialist level may be an important factor to reduce ED overcrowding.
Background and objectives:
Emergency department (ED) utilization is a major driver of health care costs. Specialist physicians have an important role in addressing ED utilization, especially at highly specialized, academic medical centers. We sought to investigate whether reporting of ED utilization to specialist physicians can decrease ED visits.
Methods:
This study analyzed an intervention to reduce ED utilization among ED patients who were followed by pediatric gastroenterologists. In May 2013, each pediatric gastroenterologist began receiving reports with rates of ED use by their patients. The reports generated discussion that resulted in a cultural and process change in which patients with urgent gastrointestinal (GI)-related complaints were preferentially seen in the office. Using control charts, we examined GI-related and all-diagnoses ED use over a 2-year period.
Results:
The rate of GI-related ED visits decreased by 60% after the intervention, from 4.89 to 1.95 per 1000 office visits (P < .001). Similarly, rates of GI-related ED visits during office hours decreased by 59% from 2.19 to 0.89 per 1000 (P < .001). Rates of all-diagnoses ED visits did not change.
Conclusions:
Physician-level reporting of ED utilization to pediatric gastroenterologists was associated with physician engagement and a cultural and process change to preferentially treat patients with urgent issues in the office.
Key findings:
The percentage of physician office and hospital outpatient department (OPD) visits during which an MRI/CT/PET scan was ordered doubled, to 4%, and the percentage of hospital emergency department visits with an MRI/CT scan more than tripled, to 16%. The percentage of physician office and OPD visits with at least five drugs prescribed more than doubled, to 25%. Inpatient hospitalization rates were similar in 2006 and 1996, but the types of procedures and surgeries performed have changed. Hospitalization rates for coronary artery stent insertions, hip replacements, and knee replacements rose sharply, while rates for some other procedures declined. Ambulatory surgery visit rates were almost twice as high in 2006 as in 1994-1996, and for some types of ambulatory procedures, such as colonoscopies, the increase was even greater.
To examine the effect of fast track on emergency department (ED) length of stay (LOS).
Pair-matched case-control design in a public teaching hospital in metropolitan Melbourne, Australia.
Patients treated by the ED fast track (cases) between 1 January and 31 March 2007 were compared with patients treated by the usual ED processes (controls) from 1 July to 15 November 2006 (n = 822 matched pairs).
ED fast track was established in November 2006 and focused on the management of patients with non-urgent complaints.
The primary outcome measure was ED LOS for fast-track patients. Secondary outcomes were waiting times and ED LOS for other ED patients.
Median ED LOS for non-admitted patients was 132 minutes (interquartile range (IQR) 83-205.25) for controls and 116 minutes (IQR 75.5-159.0) for cases (p<0.01). Fast-track patients had a significantly higher incidence of discharge within 2 h (53% vs 44%, p<0.01) and 4 h (92% vs 84%, p<0.01).
ED fast track decreased ED LOS for non-admitted patients without compromising waiting times and ED LOS for other ED patients.
Numerous reports have questioned the ability of United States emergency departments to handle the increasing demand for emergency services. Emergency department (ED) overcrowding is widespread in US cities and has reportedly reached crisis proportions. The purpose of this review is to describe how ED overcrowding threatens patient safety and public health, and to explore the complex causes and potential solutions for the overcrowding crisis. A review of the literature from 1990 to 2002 identified by a search of the Medline database was performed. Additional sources were selected from the references of the articles identified. There were four key findings. (1) The ED is a vital component of America's health care "safety net". (2) Overcrowding in ED treatment areas threatens public health by compromising patient safety and jeopardising the reliability of the entire US emergency care system. (3) Although the causes of ED overcrowding are complex, the main cause is inadequate inpatient capacity for a patient population with an increasing severity of illness. (4) Potential solutions for ED overcrowding will require multidisciplinary system-wide support.
Objective:
The aim of this retrospective study was to observe the long-term outcomes of conservative treatment and bronchial artery embolization (BAE) in patients with mild hemoptysis and to analyze the risk factors associated with hemoptysis recurrence.
Methods:
Patients with mild hemoptysis from January 2005 to January 2016 were enrolled in this study. The patients' medical records, including smoking history, etiologic diseases, bronchoscopic findings, mortality, BAE information, and follow-up data of recurrent hemoptysis, were reviewed and analyzed.
Results:
A total of 288 patients with mild hemoptysis were included in this study. Of them, 71 patients (24.7%) underwent BAE and 217 patients (75.3%) were treated conservatively. The clinical success rate of BAE was 98.6%, with a low minor complication rate of 5.6%. Bronchoscopy before treatments was performed in 237 patients (82.3%). Fifty-five patients (19.1%) experienced recurrent hemoptysis during a median follow-up period of 2.4years (interquartile range: 1.0-4.4years). Patients who showed active bleeding or blood clots on bronchoscopy had a significantly lower recurrence-free survival rate than patients with no bronchoscopic evidence of bleeding or blood clots (p=0.012). The risk factors affecting recurrence were heavy smoking (p=0.002, hazard ratio [HR]: 3.57), aspergillosis (p=0.035, HR: 6.01), and bronchoscopic findings of active bleeding (p=0.016, HR: 3.29) or blood clots (p=0.012, HR: 2.77).
Conclusions:
The recurrence rate of hemoptysis was not negligible in patients with mild hemoptysis. BAE can be considered in patients with a high risk of recurrence.
Objectives:
Emergency department (ED) utilization is a major driver of cost. Specialist physicians have an important role in addressing ED utilization, especially at tertiary medical centers that treat highly specialized patients. We analyzed if reporting of ED utilization to pediatric specialist physicians can decrease ED visits.
Methods:
Physicians within pediatric neurology, hematology and oncology, infectious diseases, and pulmonary divisions received their ED use reports. By using control charts, we examined if this intervention decreased the rate of ED utilization.
Results:
Overall, for the 4 divisions, specialty-related ED utilization decreased significantly during all hours, weekdays, and office hours. This was in the setting of ED utilization increasing for all diagnoses ED visits. Pediatric ED volume did not change during the study period.
Conclusions:
Physician-level reporting of ED utilization was associated with a reduction in ED use by patients managed by our pediatric specialists.
Background:
Epilepsy or seizure care is the most common neurologic condition that presents to an emergency department (ED) and accounts for a large number of annual cases. Our aim was to decrease seizure-related ED visits from our baseline of 17 ED visits per month per 1000 patients to 13.6 ED visits per month per 1000 patients (20%) by July 2014.
Methods:
Our strategy was to develop a quality improvement (QI) project utilizing the Institute for Healthcare Improvement model. Our defined outcome was to decrease ED utilization for children with epilepsy. Rate of ED visits as well as unplanned hospitalizations for epilepsy patients and associated health care costs were determined. A QI team was developed for this project. Plan do study act cycles were used with adjustments made when needed.
Results:
Nineteen months after implementation of the interventions, ED visits were reduced by 28% (from 17 visits per month per 1000 patients to 12.2 per month per 1000 patients) during the past year. The average number of inpatient hospitalizations per month was reduced by 43% from 7 admissions per month per 1000 patients to 4 admissions per month per 1000 patients. For both outcome measures, a 2-sample Poisson rate exact test yielded a P value < .0001. Health care claims paid were less with $115 200 reduction for ED visits and $1 951 137 reduction for hospitalizations.
Conclusions:
Applying QI methodology was highly effective in reducing ED utilization and unplanned hospitalizations for children with epilepsy at a free-standing children's hospital.
Emergency department (ED) crowding is a significant patient safety concern associated with poor quality of care. The purpose of this systematic review is to assess the relationship between ED crowding and patient outcomes.
We searched the Medline search engine and relevant emergency medicine and nursing journals for studies published in the past decade that pertained to ED crowding and the following patient outcome measures: mortality, morbidity, patient satisfaction, and leaving the ED without being seen. All articles were appraised for study quality.
A total of 196 abstracts were screened and 11 articles met inclusion criteria. Three of the eleven studies reported a significant positive relationship between ED crowding and mortality either among patients admitted to the hospital or discharged home. Five studies reported that ED crowding is associated with higher rates of patients leaving the ED without being seen. Measures of ED crowding varied across studies.
ED crowding is a major patient safety concern associated with poor patient outcomes. Interventions and policies are needed to address this significant problem.
This review details the negative patient outcomes associated with ED crowding. Study results are relevant to medical professionals and those that seek care in the ED.
Study objective:
Awaiting results from laboratory testing may sometimes be a rate-limiting step in emergency department (ED) throughput prolonging length of stay and contributing to crowding. We determine whether introduction of a comprehensive metabolic panel point-of-care test can reduce ED length of stay compared with traditional central laboratory testing.
Methods:
We performed a randomized, controlled trial among 10,244 noncritically ill ED patients aged 15 years and older whose physicians ordered a comprehensive metabolic panel at a single, large, academic, urban medical center. Participants were randomly assigned to performance of a comprehensive metabolic panel by a point-of-care test (n=5,154) or central laboratory testing (n=5,090). The primary outcome was length of stay in the ED.
Results:
A point-of-care test reduced median ED length of stay among all study patients by 22 minutes (median 350 minutes [interquartile range 206 to 1,002 minutes] with point-of-care test versus median 372 minutes [interquartile range 217 to 1,150 minutes] with central laboratory testing; median difference 22 minutes; 95% confidence interval [CI] 4 to 40 minutes). A point-of-care test also reduced ED length of stay in patients discharged to home (256 versus 268 minutes; median difference 12 minutes; 95% CI 2 to 22 minutes) and with an Emergency Severity Index triage level of 3 (333 versus 355 minutes; median difference 22 minutes; 95% CI 4 to 40 minutes).
Conclusion:
Use of a point-of-care test for a comprehensive metabolic panel reduced ED length of stay compared with central laboratory testing in the adult ED of a single academic center.
Historically, general practitioners provided first-contact care in the United States. Today, however, only 42 percent of the 354 million annual visits for acute care--treatment for newly arising health problems--are made to patients' personal physicians. The rest are made to emergency departments (28 percent), specialists (20 percent), or outpatient departments (7 percent). Although fewer than 5 percent of doctors are emergency physicians, they handle a quarter of all acute care encounters and more than half of such visits by the uninsured. Health reform provisions in the Patient Protection and Affordable Care Act that advance patient-centered medical homes and accountable care organizations are intended to improve access to acute care. The challenge for reform will be to succeed in the current, complex acute care landscape.
An Institute of Medicine (IOM) report defines six domains of quality of care: safety, patient-centeredness, timeliness, efficiency, effectiveness, and equity. The effect of emergency department (ED) crowding on these domains of quality has not been comprehensively evaluated.
The objective was to review the medical literature addressing the effects of ED crowding on clinically oriented outcomes (COOs).
We reviewed the English-language literature for the years 1989-2007 for case series, cohort studies, and clinical trials addressing crowding's effects on COOs. Keywords searched included "ED crowding,"ED overcrowding,"mortality,"time to treatment,"patient satisfaction,"quality of care," and others.
A total of 369 articles were identified, of which 41 were kept for inclusion. Study quality was modest; most articles reflected observational work performed at a single institution. There were no randomized controlled trials. ED crowding is associated with an increased risk of in-hospital mortality, longer times to treatment for patients with pneumonia or acute pain, and a higher probability of leaving the ED against medical advice or without being seen. Crowding is not associated with delays in reperfusion for patients with ST-elevation myocardial infarction. Insufficient data were available to draw conclusions on crowding's effects on patient satisfaction and other quality endpoints.
A growing body of data suggests that ED crowding is associated both with objective clinical endpoints, such as mortality, as well as clinically important processes of care, such as time to treatment for patients with time-sensitive conditions such as pneumonia. At least two domains of quality of care, safety and timeliness, are compromised by ED crowding.
This article assesses the validity of ambulatory administrative and encounter data and patient self-reported information compared with information contained in the ambulatory medical record for 17 chronic diseases. Using a sample of 213 adults (18 to 64 years old) and seniors (65 years and older) enrolled in a health maintenance organization and receiving care at multispecialty group practice in Minneapolis, Minnesota, sensitivity and specificity for claims and self-report were calculated for each chronic condition using the medical record as the criterion standard. The analysis was performed first by blinded review and then repeated with an unblinded review.
The objective of this study was to assess and compare the relative accuracy of claims data and patient self-reported information with medical records for Pap smear rates. A retrospective analysis of information obtained from administrative claims files, patient medical records, and a telephone survey was performed of 400 women age 19 through 75 years who were randomly selected for participation in the study. The data were obtained from a large multispecialty group practice in Minneapolis, Minnesota for the study years 1991 through 1993. Information from administrative claims regarding Pap smear status corresponded highly with information in the medical record (sensitivity 95% or higher; specificity 95% or higher; kappa 0.896 or better). Self-reported information from the telephone survey did not correspond well with medical record information nor with results in administrative claims.
Emergency departments (EDs) are struggling with overcrowding. The Institute for Healthcare Improvement recently concluded that reducing delays is critical to improving all aspects of emergency care. To reduce cycle times and improve patient flow, we developed a separate stream of care focused on low-acuity patients in our academic ED.
Strict triage criteria were developed, and patients were seen by a physician's assistant in a dedicated section of the ED. Two anonymous surveys (patient and staff) and a time cycle analysis were performed before and after the intervention.
Eighty-seven preintervention patient surveys (response rate = 60%) and 91 postintervention surveys (response rate = 79%) were collected. Demographic data were comparable. All domains of patient satisfaction were significantly improved in the postintervention group and were correlated with the length of stay that decreased from 127 to 53 minutes (P < .001).
This study supports an emphasis on improving turnaround time as a primary driver of satisfaction, and demonstrates that a simple intervention characterized by focusing existing resources on the needs of a specific population can significantly improve health care delivery. Thoughtful alignment of resources with the needs of specific patient populations should similarly streamline care in other clinical settings.
Research use of insurance claims data presents unique challenges and requires a series of value judgments that are intended to improve the data quality. In this study, medical insurance claims from 2 large companies were combined to assess utilization of complementary and alternative medicine. Challenges included assessing and improving the quality of data, combining data from 2 different companies with dissimilar coding systems, and determining the most appropriate ways to describe utilization. This article addresses 4 methodologic challenges in creating the analytic files: (1) conversion of claims into unique visits, (2) identification of incomplete claims data, (3) categorization of providers and locations of service, and (4) selecting the most useful measures of utilization and expenditures.
Emergency department (ED) crowding represents an international crisis that may affect the quality and access of health care. We conducted a comprehensive PubMed search to identify articles that (1) studied causes, effects, or solutions of ED crowding; (2) described data collection and analysis methodology; (3) occurred in a general ED setting; and (4) focused on everyday crowding. Two independent reviewers identified the relevant articles by consensus. We applied a 5-level quality assessment tool to grade the methodology of each study. From 4,271 abstracts and 188 full-text articles, the reviewers identified 93 articles meeting the inclusion criteria. A total of 33 articles studied causes, 27 articles studied effects, and 40 articles studied solutions of ED crowding. Commonly studied causes of crowding included nonurgent visits, "frequent-flyer" patients, influenza season, inadequate staffing, inpatient boarding, and hospital bed shortages. Commonly studied effects of crowding included patient mortality, transport delays, treatment delays, ambulance diversion, patient elopement, and financial effect. Commonly studied solutions of crowding included additional personnel, observation units, hospital bed access, nonurgent referrals, ambulance diversion, destination control, crowding measures, and queuing theory. The results illustrated the complex, multifaceted characteristics of the ED crowding problem. Additional high-quality studies may provide valuable contributions toward better understanding and alleviating the daily crisis. This structured overview of the literature may help to identify future directions for the crowding research agenda.
The effect of emergency department crowding on clinically oriented outcomes
- S L Bernstein
- D Aronsky
- R Duseja
- SL Bernstein
Evaluation of a fast track unit: alignment of resources and demand results in improved satisfaction and decreased length of stay for emergency department patients
- S W Rodi
- M Grau
- C M Orsini
- SW Rodi
Singer AJ Use of a comprehensive metabolic panel point-of-care test to reduce length of stay in the Emergency Department: a randomized controlled trial
- J Y Jang
- S S Do
- E J Lee
- C B Park
- K J Song
- JY Jang