Chang Bae Park

A trend in epidemiology and outcomes of out-of-hospital cardiac arrest by urbanization level: a nationwide observational study from 2006 to 2010 in South Korea.

BACKGROUND The goal of this study is to better understand the trend in epidemiological features and the outcomes of emergency medical service (EMS)-assessed out-of-hospital cardiac arrest (OHCA) according to the community urbanization level: metropolitan, urban, and rural. METHODS This study was performed within a nationwide EMS system with a single-tiered basic-to-intermediate service level and approximately 900 destination hospitals for eligible OHCA cases in South Korea (with 48 million people). A nationwide OHCA database, which included information regarding demographics, Utstein criteria, EMS, and hospital factors and outcomes, was constructed using the EMS run sheets of eligible cases who were transported by 119 EMS ambulances and followed by a medical record review from 2006 to 2010. Cases with an unknown outcome were excluded. The community urbanization level was categorized according to population size, with metropolitan areas (more than 500,000 residents), urban areas (100,000-500,000 residents), and rural areas (<100,000 residents). The primary end point was the survival to discharge rate. Age- and sex-adjusted survival rates (ASRs) and standardized survival ratios (SSRs) with 95% confidence intervals (CIs) were calculated compared to a standard population. The adjusted odds ratios (AORs) and 95% CIs for survival were calculated and adjusted for potential risk factors using stratified multivariable logistic regression analysis. RESULTS There were 97,291 EMS-assessed OHCAs with 73,826 (75.9%) EMS-treated cases analyzed, after excluding the patients with unknown outcome (N=4172). The standardized incidence rate increased from 37.5 in 2006 to 46.8 in 2010 per 100,000 person-years for EMS-assessed OHCAs, and the survival rate was 3.0% for EMS-assessed OHCAs (3.3% for cardiac etiology and 2.3% for non-cardiac etiology) and 3.6% for EMS-treated OHCAs. Significantly different trends were found by urbanization level for bystander CPR, EMS performance, and the level of the destination hospital. The ASRs for survival were significantly improved by year in the metropolitan areas (3.6% in 2006 to 5.3% in 2010) but remained low in the urban areas (1.4% in 2006 to 2.3% in 2010) and very low in the rural areas (0.5 in 2006 and 0.8 in 2010). The SSRs (95% CIs) in the metropolitan areas were 1.19 (1.06-1.34) in 2006 and 1.77 (1.64-1.92) in 2010, whereas the SSRs were observed to be less than 1.00 during the five-year period in both urban and rural areas. The AORs (95% CIs) for survival significantly increased to 1.42 (1.22-1.66) in the metropolitan areas and to 1.58 (1.18-2.11) in the urban areas while not increasing in the rural areas, compared to the level of each group of areas in 2006. CONCLUSIONS In this nationwide cohort study from 2006 to 2010, the standardized incidence rate and survival to discharge rate of EMS-assessed OHCAs increased annually in metropolitan and urban communities but did not increase in rural communities. Further investigations should be undertaken to improve the performance and outcomes in rural communities.

Out-of-hospital airway management and cardiac arrest outcomes: A propensity score matched analysis

OBJECTIVE It is unclear whether advanced airway management during ambulance transport is associated with improved out-of-hospital cardiac arrest (OHCA) outcomes compared with bag-valve mask ventilation (BVM). This study aimed to determine whether EMT-intermediate ETI or LMA is associated with improved OHCA outcomes in Korea. METHODS We used a Korean national OHCA cohort database composed of hospital and ambulance data. We included all EMS-treated by level 1 EMTs (EMT-intermediate level) and OHCA with presumed cardiac etiology for the period January 2006-December 2008. We excluded cases not receiving continued resuscitation in the emergency department (ED), treated by level 2 EMT, as well as those without available hospital outcome data. The primary exposure was airway management technique during ambulance transport (endotracheal tube (ETI), laryngeal mask airway (LMA) or bag-valve-mask ventilation with an oropharyngeal airway). The primary outcomes were survival to admission and survival to hospital discharge. We compared outcomes between each airway management group using multivariable logistic regression, adjusting for sex, age, witnessed, prehospital defibrillation, bystander cardiopulmonary resuscitation (CPR), call to ambulance arrival time to the scene, call to ambulance arrival time to ED, initial ECG, metropolitan (defined as population>1 million), and level of ED (higher versus lower level). We repeated the analysis using propensity-score matched subsets. RESULTS Of 54,496 patients with OHCA, we included 5278 (9.7%). Overall survival to admission and to discharge was 20.2% and 6.9%, respectively. ETI and LMA were performed in 250 (4.7%) and 391 (7.4%), respectively. In the full multivariable models using total patients, adjusted survival to admission and discharge were similar for ETI and BVM: OR 0.91 (0.66-1.27) and 1.00 (0.60-1.66), respectively. Adjusted survival to admission and discharge were significantly lower in LMA than BVM: OR 0.72 (0.54-0.95) and 0.52 (0.32-0.85), respectively. In the full multivariable models using propensity matched samples, adjusted survival to admission and discharge were similar for ETI and BVM; OR 1.32 (0.81-2.16) and 1.44 (0.66-3.15), respectively. Adjusted survival to admission was similar for LMA and BVM: OR 0.72 (0.50-1.02). However, survival to discharge was significantly lower for LMA than BVM: OR 0.45 (0.25-0.82). CONCLUSIONS In Korea, EMT-I placed LMA during ambulance transport was associated with worsened OHCA survival to discharge than BVM. Outcomes were similar between EMT-I endotracheal intubation and bag-valve-mask ventilation.

Dispatcher-assisted bystander cardiopulmonary resuscitation in a metropolitan city: A before–after population-based study

BACKGROUND The goal of this study was to determine the effects of dispatcher-assisted bystander cardiopulmonary resuscitation (DA-CPR) on outcomes of out-of-hospital cardiac arrest (OHCA). METHODS All EMS in a metropolitan city with a population of 10 million are dispatched by a single, centralized, and physician-supervised center. Data on patients with adult OHCA with cardiac etiology were collected from the dispatch center registry and from EMS run sheets and hospital medical record review from 2009 to 2011. A standardized DA-CPR protocol (aligned with the 2010 AHA guidelines) we implemented as an intervention in January 2011. The end points were survival to discharge, good neurological outcome, and bystander CPR rate. Multivariate logistic analysis was used to compare between intervention group (2011) and historical control group (2009-2010). RESULTS Of 8.144 eligible patients, bystander CPR was performed for the patients in 5.7% (148/2600) of cases in 2009, 6.7% (190/2857) in 2010, and 12.4% (334/2686) in 2011 (p<0.001). The survival to discharge rates was 7.1% (2009), 7.1% (2010), and 9.4% (2011) (p=0.001). Good neurological outcomes occurred in 2.1% (2009), 2.0% (2010), and 3.6% (2011) of cases (p<0.001). The adjusted ORs (95% CIs) for survival to discharge compared with 2009 were 1.33 (1.07-1.66) in 2011 and 1.12 (0.89-1.41) in 2010. The adjusted ORs (95% CIs) for good neurological outcomes were 1.67 (1.13-2.45) in 2011 and 1.13 (0.74-1.72) in 2010. CONCLUSIONS An EMS intervention using the DA-CPR protocol was associated with a significant increase in bystander CPR and an improved survival and neurologic outcome after OHCA.

Pediatric out-of-hospital cardiac arrest in Korea: A nationwide population-based study☆☆☆

STUDY OBJECTIVES Our objective was to describe the incidence and demographics of pediatric out-of-hospital cardiac arrest (OHCA) in Korea. METHODS We identified non-traumatic OHCA patients aged less than 20 years from a Korean nationwide OHCA registry (2006-2007). Data from emergency medical service (EMS) run-sheets and hospital records were reviewed. We excluded cases with unknown hospital outcomes. Patient characteristics, treatment by EMS, and outcomes were compared by age groups: infant (<1 year), children (1-11 years), and adolescents (12-19 years). RESULTS A total of 971 patients including infants (n=299, 30.8%), children (n=305, 31.4%), and adolescents (n=367, 37.8%) met inclusion criteria. The incidence of pediatric OHCA was 4.2 per 100,000 person-years (67.1 in infants, 2.5 in children, and 3.5 in adolescents). The rate of cardiopulmonary resuscitation administered was 82.1% (infants 80.6%, children 82.0%, and adolescent 83.4%). The rate of applying automated external defibrillators and advanced airway management (endotracheal intubation or laryngeal mask airway), was only 4.1% and 2.5%, respectively. 7.4% showed ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) in the initial ECG. Survival to hospital discharge for all pediatric OHCA was 4.9% (2.9% for infants, 4.7% for children, and 7.2% of adolescents). For EMS-treated pediatric OHCA or patients with VF or pulseless VT, the rate was 5.0% and 31.6%, respectively. CONCLUSION Incidence and hospital outcomes in pediatric OHCA in Korea were comparable to other population-based nationwide reports.

Comparison of clinical performance of cranial computed tomography rules in patients with minor head injury: a multicenter prospective study.

OBJECTIVES The objective was to compare the predictive performance of three previously derived cranial computed tomography (CT) rules, the Canadian CT Head Rule (CCHR), the New Orleans Criteria (NOC), and National Emergency X-Ray Utilization Study (NEXUS)-II, for detecting clinically important traumatic brain injury (TBI) and the need for neurosurgical intervention in patients with blunt head trauma. METHODS This was a prospective, multicenter, observational cohort study of patients with blunt head trauma from June 2008 to May 2009. The historical and physical examination components of the CCHR, NOC, and NEXUS-II were documented on a data collection form and the performance of each of the three rules was compared. Patient eligibility for each specific rule was defined exactly as previously described for each specific rule. To compare the three decision rules in terms of sensitivity and specificity, an intersection cohort satisfying inclusion criteria of all three decision rules was derived. The primary outcome was clinically important TBI, and the secondary outcome was neurosurgical intervention. The sensitivity and specificity of each rule were calculated with 95% confidence intervals (95% CIs). We also calculated the potential reduction rate in cranial CT scan utilization realized by theoretical implementation of these rules. RESULTS A total of 7,131 patients were prospectively enrolled, including 692 (9.7%) with clinical TBI. Among the enrolled population, patients eligible for CCHR, NOC, and NEXUS-II totaled 696, 677, and 2,951, respectively. The sensitivity and specificity for clinically important brain injury were as follows: CCHR, 112 of 144 (79.2%, 95% CI = 70.8% to 86.0%) and 228 of 552 (41.3%, 95% CI = 37.3% to 45.5%); NOC, 91 of 99 (91.9%, 95% CI = 84.7% to 96.5%) and 125 of 558 (22.4%, 95% CI = 19.0% to 26.1%); and NEXUS-II, 511 of 576 (88.7%, 95% CI = 85.8% to 91.2%) and 1,104 of 2,375 (46.5%, 95% CI = 44.5% to 48.5%). The sensitivity and specificity for neurosurgical intervention were as follows: CCHR, 100% (95% CI = 59.0% to 100.0%) and 38.3% (95% CI = 34.5% to 41.9%); NOC, 100% (95% CI = 54.1% to 100.0%) and 20.4% (95% CI = 17.4% to 23.7%); and NEXUS-II, 95.1% (95% CI = 90.1% to 98.0%) and 41.4% (95% CI = 39.5% to 43.2%). Among the enrolled population, intersection patients of CCHR, NOC, and NEXUS-II totaled 588. The sensitivity and specificity for clinically important brain injury were as follows: CCHR, 73 of 98 (74.5%, 95% CI = 64.7% to 82.8%) and 201 of 490 (41.0%, 95% CI = 36.6% to 45.5%); NOC, 89 of 98 (90.8%, 95% CI = 83.3% to 95.7%) and 112 of 490 (22.9%, 95% CI = 19.2% to 26.8%); and NEXUS-II, 82 of 98 (83.7%, 95% CI = 74.8% to 90.4%) and 172 of 490 (35.1%, 95% CI = 30.9% to 39.5%). The potential reduction in emergency CT scans by using these decision rules would have been higher with the NEXUS-II rule (39.6%, 95% CI = 37.8% to 41.4%) than with the CCHR rule (27.0%, 95% CI = 23.7% to 30.3%) or NOC rule (20.2%, 95% CI = 17.2% to 23.3%). CONCLUSIONS For clinically important TBI, the three cranial CT decision rules had much lower sensitivities in this population than the original published studies, while the specificities were comparable to those studies. The sensitivities for neurosurgical intervention, however, were comparable to the original studies. The NEXUS-II rule showed the highest reduction rate for CT scans compared to other rules, but failed to identify all undergoing neurosurgical intervention for their original inclusion cohort.

Post-resuscitation care and outcomes of out-of-hospital cardiac arrest: A nationwide propensity score-matching analysis

OBJECTIVE This study aimed to determine whether active post-resuscitation care (APRC) was associated with improved out-of-hospital cardiac arrest (OHCA) outcomes on a nationwide level. METHODS AND RESULTS We used a national OHCA cohort database consisting of hospital and ambulance data. We included all survivors of OHCA, excluding patients with non-cardiac etiology, younger than 15 years, and with unknown outcomes, from (2008 to 2010). The APRC was defined when the OHCA patients received mild therapeutic hypothermia (MTH) or active cardiac care (ACC), such as intravenous thrombolysis, percutaneous coronary intervention, coronary artery bypass surgery, and pacemaker/implantable cardioverter defibrillator insertion, as well as routine intensive care; patients receiving conservative post-resuscitation care (CPRC) served as the other group. The primary and secondary outcomes were survival to discharge and a good neurological outcome (cerebral performance category [CPC] 1-2), respectively. We extracted propensity-matched samples to control for selection bias. A multivariable logistic regression analysis was used to compare the APRC and CPRC groups adjusting for potential risks to calculate the adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs). Of total 64,155 patients, 4557 survived to admission and were included in the final analysis. Out of these patients, 1599 (35.1%) cases survived to discharge, and 499 (11.0%) cases were discharged with good neurological recoveries. Overall, 695 cases (15.3%) received any APRC, including MTH (n=377, 8.3%) and ACC (370, 8.1%). The outcomes was better in the APRC group than in the CPRC group for survival to discharge (58.7% vs. 30.8%, p<0.001) and good neurological outcome (27.2% vs. 8.0%, p<0.001), respectively. In the total cohort, the adjusted ORs of the APRC group compared to those the CPRC group were 2.15 (95% CI 1.78-2.59) for survival to discharge and 2.54 (95% CI 1.98-3.27) for a good neurological outcome. In the propensity score-matched cohort, the adjusted ORs for survival to discharge and good neurological outcome of APRC were significantly favorable. CONCLUSIONS Active post-resuscitation care resulted in significantly improved outcomes in adult OHCA patients with a presumed cardiac etiology in a nationwide, retrospective, observational study.

A comparison of outcomes of out-of-hospital cardiac arrest with non-cardiac etiology between emergency departments with low- and high-resuscitation case volume.

OBJECTIVES It is unclear whether outcome after out-of-hospital cardiac arrest (OHCA) of non-cardiac etiology (NCE) is associated with the volume of patients with OHCA received annually at the emergency department (ED) where they receive treatment. This study evaluated whether the volume of patients treated is associated with better outcomes for non-cardiac OHCA patients. METHODS This study was performed in an emergency medical service (EMS) system with a single-tiered basic-to-intermediate service level and approximately 410 destination hospitals for eligible OHCA cases. A nationwide OHCA database (2006-2008), constructed from EMS run sheets, and a hospital medical record review were used. OHCA was defined as pulseless and unresponsive in the field. Included in the study were cases treated with OHCA whose etiology was non-cardiac. Excluded were cases with unknown hospital outcome. The cutoff number for a high volume (HV) versus a low volume (LV) of cardiopulmonary resuscitation (CPR) cases was calculated using a threshold model. The primary end points were survival to admission and survival to discharge. The adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for the endpoints were calculated, adjusting for potential predictors. RESULTS There were 10,425 eligible patients (trauma 5735; drowning 98; poisoning 684; asphyxia 1413; and hanging 1605). The survival-to-admission and the survival-to-discharge rates of the study participants were 9.6% and 2.4%, respectively. The cutoff number for case volume was 38 per year. The rates of survival to admission and survival to discharge were significantly higher in the HV (18.6% and 5.1%, respectively) group when compared to the LV group (5.9% and 1.3%, respectively). For the treated, non-cardiac OHCA patients, the adjusted ORs in the HV group compared to the LV group were 2.16 for survival to admission (95% CI: 1.84-2.55) and 2.58 for survival to discharge (95% CI: 1.90-3.52). The survival-to-discharge rate was significantly higher in the HV group than in the LV group for each cause: trauma 2.1% vs. 0.6%, drowning 6.8% vs. 1.9%, poisoning 8.6% vs. 1.7%, asphyxia 13.5% vs. 3.8%, and hanging 5.2% vs. 1.3%, respectively. CONCLUSION This national cohort study suggests that greater survival to admission as well as discharge for patients with OHCA of NCE is associated with greater annual volume of patients with OHCA treated at that hospital.

Use of a Comprehensive Metabolic Panel Point-of-Care Test to Reduce Length of Stay in the Emergency Department: A Randomized Controlled Trial

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.

Diagnostic Accuracy of Focused Assessment with Sonography for Trauma (FAST) Examinations Performed by Emergency Medical Technicians

Abstract Objective. We aimed to assess the diagnostic accuracy of focused assessment with sonography for trauma (FAST) examinations when used by emergency medical technicians (EMTs) to detect the presence of free abdominal fluid. Methods. Six level 1 EMTs (similar to intermediate EMTs in the United States) who worked at a tertiary emergency department in Korea underwent an educational program consisting of two one-hour didactic lectures that included the principles of ultrasonography, the anatomy of the abdomen, and two hours of hands-on practice. After this educational session, the EMTs performed FAST examinations on a convenience sample of patients from July 1 to October 5, 2009. These patients also received an abdominal computed tomography (CT) scan regardless of their chief complaints. The CT findings served as the definitive standard and were interpreted routinely and independently by emergency radiologists who were blinded to the study protocol. In addition, the EMTs were blinded to the CT findings. A positive CT finding was defined as the presence of free fluid, as interpreted by the radiologist. The sensitivity, specificity, predictive values, and their 95% confidence intervals (CIs) were calculated. Informed consent was obtained from all participating patients. Results. Among the 1,060 eligible patients with abdominal CT scans, 403 patients were asked to participate in the study, and 240 patients agreed. Of these 240 patients, 80 (33.3%) had results showing the presence of free fluid. Fourteen patients had a significant amount of peritoneal cavity fluid, 15 had a moderate amount of peritoneal cavity fluid, and 51 had a minimal amount of peritoneal cavity fluid. Compared with the CT findings, the diagnostic performance of the FAST examination had a sensitivity of 61.3% (95% CI, 50.3%–71.2%), specificity of 96.3% (95% CI, 92.1%–98.3%), positive predictive value of 89.1% (95% CI, 77.0%–95.4%), and negative predictive value of 83.2% (95% CI, 76.9%–88.2%). For a significant or moderate amount of peritoneal cavity fluid, the sensitivity was considerably higher (86.2%). Conclusion. EMTs in Korea showed a high diagnostic performance that was comparable to that of surgeons and physicians when detecting peritoneal cavity free fluid in a Korean emergency department setting. The validity of FAST examinations in prehospital care situations should be investigated further.

Epidemiology and Outcomes of Poisoning-induced Out-of-Hospital Cardiac Arrest

OBJECTIVES We aimed to describe and compare the epidemiologic features and outcomes among patients with poisoning-induced out-of-hospital cardiac arrests (POHCAs) according to causative agent groups. METHODS We identified emergency medical service (EMS)-treated POHCA patients from a nationwide OHCA registry between 2006 and 2008, which was derived from EMS run sheets and followed by hospital record review. Utstein elements were collected and hospital outcomes (survival to admission and to discharge) were measured. We compared risk factors and outcomes according to the main poisons. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from a multivariate logistic regression model for hospital outcomes. RESULTS The total number of non-cardiac aetiology OHCAs was 20,536. Of these, the number of EMS-assessed and EMS-treated POHCAs was 900 (4.4%). For EMS-treated POHCAs, insecticides (n=111, 15.5%) including organophosphate and carbamates; herbicides (n=94, 13.2%); unknown pesticides (n=142, 19.9%); non-pesticide drugs (n=120, 16.8%); and unknown poisons (n=247, 6%) were identified. The survival to admission rate was 22.5% for insecticides, 3.2% for herbicides, 16.2% for unknown pesticides, 16.7% for non-pesticides and 11.3% for the unknown group. The survival to discharge rates were 9.9% for insecticides, 0.0% for herbicides, 2.1% for unknown pesticides, 3.3% for non-pesticides and 3.2% for the unknown group. The adjusted OR for each group for survival to admission was significantly lower when compared with insecticides: herbicides (OR=0.11, 95% CI=0.03-0.44), non-pesticide drugs (OR=0.28, 95% CI=0.13-0.61) and unknown group (OR=0.40, 95% CI=0.21-0.76). The adjusted OR for each group for survival to discharge was significantly lower when compared with insecticides: herbicides (OR<0.01, 95% CI<0.01 or >99.9), unknown pesticides (OR=0.23, 95% CI=0.0.06-0.87), non-pesticide drugs (OR=0.14, 95% CI=0.04-0.54) and unknown group (OR=0.30, 95% CI=0.11-0.83). CONCLUSION Using a nationwide OHCA registry, we found that poisonings were responsible for 4.4% of OHCAs of a non-cardiac aetiology. Ingestion of insecticides including organophosphate and carbamate was associated with more favourable outcomes.