Billing diagnoses do not accurately identify out-of-hospital cardiac arrest patients: An analysis of a regional healthcare system

Validation of ICD-10 codes for studying foreign body airway obstructions: A health administrative data cohort study

Aim

To validate a case definition for foreign body airway obstructions (FBAO) using International Classification of Diseases version 10 (ICD-10) codes to accurately identify patients in administrative health databases and improve reporting on this injury.

Methods

We identified prehospital patient encounters in Alberta, Canada between Jan 1, 2018 and Dec 31, 2021 by querying the provincial emergency medical services' (EMS) patient care records for FBAO-related presentations, EMS protocols, or treatments. We deterministically linked EMS patient encounters to data on emergency department visits and hospital admissions, which included ICD-10 codes. Two physicians independently reviewed encounters to determine true FBAO cases. We then calculated diagnostic accuracy measures (sensitivity, specificity, likelihood ratios) of various algorithms.

Results

We identified 3677 EMS patient encounters, 2121 were linked to hospital administrative databases. Of these encounters, 825 (38.9%) were true FBAO. The combination of two ICD-10 codes (T17 = foreign body in the respiratory tract or T18.0 = foreign body in the mouth) was the most specific algorithm (96.9% [95%CI 95.8-97.8%]), while the combination of all FBAO-related ICD-10 codes and R06.8 (other breathing abnormalities) was the most sensitive (75.0% [95%CI 71.9-78.0]). We identified an additional 453 (35.4%) FBAO cases not transported by EMS (due to death or transport refusal), and therefore not linked to the hospital administrative databases. Of these unlinked encounters, 44 (9.7%) cases resulted in the patient's death.

Conclusions

FBAO can be identified with reasonable accuracy using health administrative data and ICD-10 codes. All algorithms had a trade-off between sensitivity and specificity, and failed to identify a third of FBAO cases, of which 10% resulted in death.

Inconsistent discharge diagnoses for young cardiac arrest episodes: insights from a statewide registry

BACKGROUND

Administrative coding of out-of-hospital cardiac arrest (OHCA) is heterogeneous, with the prevalence of noninformative diagnoses uncertain.

AIM

To characterize the prevalence and type of non-informative diagnoses in a young cardiac arrest population.

METHODS

Hospital discharge diagnoses provided to a statewide OHCA registry were characterised as either 'informative' or 'noninformative.' Informative diagnoses stated an OHCA had occurred or defined OHCA as occurring due to coronary artery disease, cardiomyopathy, channelopathy, definite noncardiac cause, or no known cause. Noninformative diagnoses were blank, stated presenting cardiac rhythm only, provided irrelevant information or presented a complication of the OHCA as the main diagnosis. Characteristics of patients receiving informative versus noninformative diagnoses were compared.

RESULTS

Of 1479 patients with OHCA aged 1 to 50 years, 290 patients were admitted to 15 hospitals. Ninety diagnoses (31.0%) were noninformative (arrest rhythm = 50, blank = 21, complication = 10 and irrelevant = 9). Two hundred diagnoses (69.0%) were informative (cardiac arrest = 84, coronary artery disease = 54, noncardiac diagnosis = 48, cardiomyopathy = 8, arrhythmia disorder = 4 and unascertained = 2). Only 10 diagnoses (3.5%) included both OHCA and an underlying cause. Patients receiving a noninformative diagnosis were more likely to have survived OHCA or been referred for forensic assessment (P = 0.011) and had longer median length of stay (9 vs 5 days, P = 0.0019).

CONCLUSION

Almost one third of diagnoses for young patients discharged after an OHCA included neither OHCA nor any underlying cause. Underestimating the burden of OHCA impacts ongoing patient and at-risk family care, data sampling strategies, international statistics and research funding.

Comparing strategies for prehospital transport to specialty care after cardiac arrest

Outcomes are better when patients resuscitated from out-of-hospital cardiac arrest (OHCA) are treated at specialty centers. The best strategy to transport patients from the scene of resuscitation to specialty care is unknown.

METHODS

We performed a retrospective cohort study. We identified patients treated at a single specialty center after OHCA from 2010 to 2021 and used OHCA geolocations to develop a catchment area using a convex hull. Within this area, we identified short term acute care hospitals, OHCA receiving centers, adult population by census block group, and helicopter landing zones. We determined population-level times to specialty care via: (1) direct ground transport; (2) transport to the nearest hospital followed by air interfacility transfer; and (3) ground transport to air ambulance. We used an instrumental variable (IV) adjusted probit regression to estimate the causal effect of transport strategy on functionally favorable survival to hospital discharge.

RESULTS

Direct transport to specialty care by ground to air ambulance had the shortest population-level times from OHCA to specialty care (median 56 [IQR 47-66] minutes). There were 1,861 patients included in IV regression of whom 395 (21%) had functionally favorable survival. Most (n = 1,221, 66%) were transported to the nearest hospital by ground EMS then to specialty care by air. Patient outcomes did not differ across transport strategies in our IV analysis.

DISCUSSION

We did not find strong evidence in favor of a particular strategy for transport to specialty care after OHCA. Population level time to specialty care was shortest with ground ambulance transport to the nearest helicopter landing zone.

Value Placed on Comfort vs Life Prolongation Among Patients Treated With Maintenance Dialysis

Importance

Patients receiving maintenance dialysis experience intensive patterns of end-of-life care that might not be consistent with their values.

Objective

To evaluate the association of patients' health care values with engagement in advance care planning and end-of-life care.

Design, Setting, and Participants

Survey study of patients who received maintenance dialysis between 2015 and 2018 at dialysis centers in the greater metropolitan areas of Seattle, Washington, and Nashville, Tennessee, with longitudinal follow-up of decedents. Logistic regression models were used to estimate probabilities. Data analysis was conducted between May and October 2022.

Exposures

A survey question about the value that the participant would place on longevity-focused vs comfort-focused care if they were to become seriously ill.

Main Outcomes and Measures

Self-reported engagement in advance care planning and care received near the end of life through 2020 using linked kidney registry data and Medicare claims.

Results

Of 933 patients (mean [SD] age, 62.6 [14.0] years; 525 male patients [56.3%]; 254 [27.2%] identified as Black) who responded to the question about values and could be linked to registry data (65.2% response rate [933 of 1431 eligible patients]), 452 (48.4%) indicated that they would value comfort-focused care, 179 (19.2%) that they would value longevity-focused care, and 302 (32.4%) that they were unsure about the intensity of care they would value. Many had not completed an advance directive (estimated probability, 47.5% [95% CI, 42.9%-52.1%] of those who would value comfort-focused care vs 28.1% [95% CI, 24.0%-32.3%] of those who would value longevity-focused care or were unsure; P < .001), had not discussed hospice (estimated probability, 28.6% [95% CI, 24.6%-32.9%] comfort focused vs 18.2% [95% CI, 14.7%-21.7%] longevity focused or unsure; P < .001), or had not discussed stopping dialysis (estimated probability, 33.3% [95% CI, 29.0%-37.7%] comfort focused vs 21.9% [95% CI, 18.2%-25.8%] longevity focused or unsure; P < .001). Most respondents wanted to receive cardiopulmonary resuscitation (estimated probability, 78.0% [95% CI, 74.2%-81.7%] comfort focused vs 93.9% [95% CI, 91.4%-96.1%] longevity focused or unsure; P < .001) and mechanical ventilation (estimated probability, 52.0% [95% CI, 47.4%-56.6%] comfort focused vs 77.9% [95% CI, 74.0%-81.7%] longevity focused or unsure; P < .001). Among decedents, the percentages of participants who received an intensive procedure during the final month of life (estimated probability, 23.5% [95% CI, 16.5%-31.0%] comfort focused vs 26.1% [95% CI, 18.0%-34.5%] longevity focused or unsure; P = .64), discontinued dialysis (estimated probability, 38.3% [95% CI, 32.0%-44.8%] comfort focused vs 30.2% [95% CI, 23.0%-37.8%] longevity focused or unsure; P = .09), and enrolled in hospice (estimated probability, 32.2% [95% CI, 25.7%-38.7%] comfort focused vs 23.3% [95% CI, 16.4%-30.5%] longevity focused or unsure; P = .07) were not statistically different.

Conclusions and Relevance

This survey study found that there appeared to be a disconnect between patients' expressed values, which were largely comfort focused, and their engagement in advance care planning and end-of-life care, which reflected a focus on longevity. These findings suggest important opportunities to improve the quality of care for patients receiving dialysis.

Influence of advanced life support response time on out-of-hospital cardiac arrest patient outcomes in Taipei

Background

The association between out-of-hospital cardiac arrest patient survival and advanced life support response time remained controversial. We aimed to test the hypothesis that for adult, non-traumatic, out-of-hospital cardiac arrest patients, a shorter advanced life support response time is associated with a better chance of survival. We analyzed Utstein-based registry data on adult, non-traumatic, out-of-hospital cardiac arrest patients in Taipei from 2011 to 2015.

Methods

Patients without complete data, witnessed by emergency medical technicians, or with response times of ≥ 15 minutes, were excluded. We used logistic regression with an exposure of advanced life support response time. Primary and secondary outcomes were survival to hospital discharge and favorable neurological outcomes (cerebral performance category ≤ 2), respectively. Subgroup analyses were based on presenting rhythms of out-of-hospital cardiac arrest, bystander cardiopulmonary resuscitation, and witness status.

Results

A total of 4,278 cases were included in the final analysis. The median advanced life support response time was 9 minutes. For every minute delayed in advanced life support response time, the chance of survival to hospital discharge would reduce by 7% and chance of favorable neurological outcome by 9%. Subgroup analysis showed that a longer advanced life support response time was negatively associated with the chance of survival to hospital discharge among out-of-hospital cardiac arrest patients with shockable rhythm and pulse electrical activity groups.

Conclusions

In non-traumatic, adult, out-of-hospital cardiac arrest patients in Taipei, a longer advanced life support response time was associated with declining odds of survival to hospital discharge and favorable neurologic outcomes, especially in patients presenting with shockable rhythm and pulse electrical activity.

Clinical and Economic Burden of Out-of-Hospital Cardiac Arrest in US Commercial Insurance Population (2014 to 2019)

Little is known about the economic burden incurred by out-of-hospital cardiac arrest (OHCA) in the US commercial insurance setting. We used IBM MarketScan Commercial Claims and Encounters Database (January 2014 to March 2019) to identify patients hospitalized with OHCA based on the International Classification of Diseases codes. Patients who survived the initial OHCA episode were stratified by prognosis based on discharge setting and classified into mild (discharged home), moderate (skilled nursing facility), severe (inpatient rehabilitation or long-term hospital), and very severe (hospice) prognosis groups, respectively. Patients were followed up for 12 months after discharge for health care resource utilization and medical costs, which were inflated to year 2020. Overall, 23,512 patients with OHCA hospitalization were identified, of whom 14,667 were <65 years and 60.5% were men. The incidence of OHCA per 100,000 was steady in patients <65 years over the years (17.9 in 2014; 17.5 in 2018) but among those ≥65 years, decreased from 139.7 in 2014 to 111.1 in 2018. Total medical costs 12 months after discharge generally increased with severity of prognosis, with an average for the mild, moderate, and severe prognosis group, respectively, estimated to be $52,746, $100,394, and $130,530 among patients <65 years, and $63,194, $65,794, and $70,973 among those ≥65 years. Costs were lower for those with very severe prognosis ($7,102 for <65 years; $2,553 for ≥65 years), possibly due to high mortality. In conclusion, OHCA continues to pose a substantial clinical and economic burden on patients and the US health care system, which increases with the severity of disease prognosis.

Increased Cardiac Arrhythmia After Pregnancy-Induced Hypertension: A South Korean Nationwide Database Study

Background

Although pregnancy‐induced hypertension (PIH) is associated with an elevated cardiovascular risk, long‐term studies or prepregnancy baseline data are scarce. Therefore, using a large nationwide cohort with prepregnancy periodic health screening data, we investigated whether clinically significant arrhythmia incidence increases after PIH.

Methods and Results

Data were extracted from the Korea National Health Insurance database and combined with the National Health Screening Examination database; women who gave birth between 2007 and 2015 and underwent the national health screening test within a year before pregnancy were followed up until 2016. We excluded women who had a diagnosis of arrhythmia within 1 year before pregnancy. The primary outcome was significant arrhythmia during the year after delivery. Secondary analysis included only specific diagnostic codes of arrhythmia with clinical significance. Additionally, the risk of arrhythmia was stratified by the use of magnesium sulfate. Of 2 035 684 women (PIH; n=37 297 versus normotensive pregnancy; n=1 998 387), the PIH group had a higher prepregnancy risk profile and showed a higher incidence of arrhythmia than women with normotensive pregnancies within 1 year. Women with PIH had a significantly higher risk of atrial flutter/fibrillation and atrioventricular block, but not lethal arrhythmias. Other predictors of arrhythmia development included advanced maternal age and cesarean section. Stratified analysis showed a higher risk of arrhythmia with magnesium sulfate use.

Conclusions

PIH was significantly associated with the development of arrhythmia within 1 year after delivery. Nevertheless, the incidence of lethal arrhythmias was not increased by PIH. Arrhythmia, especially atrial fibrillation, may largely contribute to increasing the future cardiovascular risk in women with a PIH history.

Case completeness in the Norwegian Cardiac Arrest Registry

Introduction

This study aimed to assess the case completeness of out-of-hospital cardiac arrests (OHCA) in the Norwegian Cardiac Arrest Registry (NorCAR) and describe the differences between the registered and missing patients identified from the case-control assessment.

Methods

We identified the relevant patients in the Norwegian Patient Registry and the Norwegian Cause of Death Registry and compared them with the patients in NorCAR. Data processors used patient records to confirm if the potential cardiac arrest cases met the inclusion criteria in NorCAR.

Results

Between 2015 and 2017, 8612 OHCA patients were registered in NorCAR. Through the Patient Registry and the Cause of Death Registry we identified 11,114 potential OHCA patients, 3469 of these were already registered in NorCAR. After evaluating the patient records for the remaining 7645 patients, we found 344 patients (4%), were eligible for inclusion in NorCAR, giving a case completeness of 96%. The registered and missing patients were similar in age and gender distribution. Initial shockable rhythm and presumed cause were also comparable. However, the missing patients more frequently achieved return of spontaneous circulation, were more often transported to hospital, and had higher survival rates. The already registered patients had more key variables registered than the missing patients.

Conclusion

Our results indicate high case completeness in NorCAR. The missing patients were too few to introduce significant changes in the distribution of patient characteristics, indicating that NorCAR is representative of the Norwegian OHCA population.

Cardiovascular Safety of Metoclopramide Compared to Domperidone: A Population-Based Cohort Study

BACKGROUND

Metoclopramide and domperidone are common prokinetics used to alleviate gastrointestinal symptoms. However, both drugs may trigger ventricular arrhythmias.

AIM

We conducted this population-based study to compare the 30-day cardiovascular safety of metoclopramide versus domperidone in outpatient care.

METHODS

We used health care databases to identify a cohort of patients in Ontario, Canada newly dispensed metoclopramide or domperidone. Inverse probability of treatment weighting based on propensity scores was used to balance the baseline characteristics of the two groups. All outcomes were assessed in the 30 days following drug dispensing. The primary outcome was hospital encounter with ventricular arrhythmia. The secondary outcomes were hospital encounter with cardiac arrest, all-cause mortality and cardiovascular mortality.

RESULTS

We identified 196,544 patients, 19% of whom were prescribed metoclopramide. There was no difference in the risk of a hospital encounter with ventricular arrythmia (0.02% in both groups), or cardiac arrest (0.10% with metoclopramide and 0.08% with domperidone). However, 1.34% of patients died after starting metoclopramide compared to 0.52% of patients starting domperidone; weighted risk ratio 2.50 (95% confidence interval [CI] 2.13 to 3.03). Similarly, 0.42% of patients died of cardiovascular causes after starting metoclopramide compared to 0.19 % of patients starting domperidone; weighted risk ratio 2.00 (95% CI 1.44 to 2.77).

CONCLUSION

The 30-day risk for a hospital encounter with ventricular arrhythmia was low for both metoclopramide and domperidone, with no significant difference in the rate between the two drugs. The higher 30-day risk of death observed with metoclopramide compared with domperidone in this study has also been observed in other studies and warrants further investigation.

Overcoming challenges of establishing a hospital-based out-of-hospital cardiac arrest registry: accuracy of case identification using administrative data and clinical registries

INTRODUCTION

Comprehensive identification of out-of-hospital cardiac arrest (OHCA) cases for inclusion in registries remains challenging due to the inherent diversity of OHCA aetiology, presentation, and management. The Northern Adelaide Local Health Network (NALHN) OHCA registry identifies OHCAs presenting to NALHN hospitals using existing data sources to monitor in-hospital treatment and survival. This study aimed to investigate the accuracy of hospital-based data sources for identifying OHCA cases treated at hospital.

METHODS

Retrospective analysis of all OHCAs aged >18 years included in the NALHN OHCA registry between 2011-16. Registry cases are identified from an emergency medical service (EMS) OHCA registry, Emergency Department (ED) and ICD-10 coding datasets, and key-word searches of two in-hospital clinical registries. Sensitivity and positive predictive values (PPV) of each hospital-based data source were analysed with respect to (a) the number of cases expected to be identified by that source, (b) total OHCA. Non-OHCAs yielded by each source were explored and a sub-analysis of ICD-10 codes was performed.

RESULTS

Between 2011-16, the four hospital-based sources yielded 992 cases, of which 383 were confirmed as OHCA. The ED coding dataset was the most accurate with a sensitivity and PPV of 78%. The ICD-10 coding dataset had good sensitivity but low PPV (33%). The ED coding dataset, combined with the two in-hospital clinical registries, identified 93% of OHCAs.

CONCLUSIONS

No single dataset identified all OHCAs presenting to NALHN hospitals. Combined hospital-based data sources provide a valid method of identifying OHCAs treated at hospital that may be adapted to augment EMS-based data.

Cardiovascular Events after the Sewol Ferry Disaster, South Korea

BACKGROUND

Major incidents affecting large numbers of people may increase the rate of acute cardiovascular events, even among those who are not directly involved in the incident. It is hypothesized that the MV Sewol ferry disaster (South Korea) would increase the incidence of cardiovascular events nation-wide.

METHODS

Data on all adult patients (&gt;18 years) who were diagnosed with acute cardiovascular events, including acute myocardial infarction (MI), angina, and cardiac arrhythmias, were extracted from the National Emergency Department Information System (NEDIS) from March 15 through June 17, during the years 2011-2014 (four weeks before to eight weeks after the event date). Poisson regression models were used to calculate the incidence rate ratios (IRRs) comparing the weekly changes in the occurrences of cardiovascular events from the week of the Sewol event (April 16-22, 2014) to eight weeks after the disaster (June 11-17, 2014), using the one-month period before Sewol as a reference period (March 15-April 15), adjusting for calendar years (years 2011-2014) and environmental factors.

RESULTS

During the study periods, cardiovascular events were identified in 73,823 patients. Compared to the reference period, the week of the Sewol disaster and the three weeks after the disaster showed a significant increase in the number of acute cardiovascular events, IRRs of 1.09 (95% CI, 1.03-1.15) and 1.08 (95% CI, 1.02-1.15), respectively (P &lt;.01 for both). In particular, there was 21% increase in incidence of arrhythmia (IRR = 1.21; 95% CI, 1.02-1.44; P = .03) during the week of the Sewol disaster compared with the reference period.

CONCLUSION

This study showed a significant increase in the incidence of acute cardiovascular events during the week of, and the three weeks after, the Sewol ferry disaster in 2014. These additional cardiac emergencies may be triggered by emotional stressors related to the event, highlighting the public health importance of indirect exposure to a tragic catastrophe.Kong SY, Song KJ, Shin SD, Ro YS. Cardiovascular events after the Sewol ferry disaster, South Korea. Prehosp Disaster Med. 2019;34(2):142-148.

Pre-existing comorbidity modify emergency room visit for out-of-hospital cardiac arrest in association with ambient environments

Background

This study evaluated risks of emergency room visit (ERV) for out-of-hospital cardiac arrest (OHCA) in 2005–2011, among patients with cardiologic and metabolic syndromes (CMS), in association with ambient environments.

Methods

Pooled and area-specific weather related cumulative six-day (lags 0 to 5) relative risks (RRs) and confidence intervals (CIs) of ERV for OHCA were evaluated for CMS cases, using distributed lag nonlinear models and multivariate meta-analytical second-stage model in association with the daily average temperatures and daily concentrations of air pollutants.

Results

ERV risk increased as average temperature dropped to <27°C. At the mean temperature of 14°C, the cumulative six-day RRs of ERV were 1.73 (95% CI: 1.22, 2.46) for all OHCA patients, 1.74 (95% CI: 1.06, 2.84) for OHCA patients younger than 65 years old, and 1.99 (95% CI: 1.03, 3.81) for subjects with pre-existing hypertension. High temperature was also associated with elevated ERV of OHCA. Increased ERV risks in cases with pre-existing hypertension and diabetes mellitus were also associated with concentrations of air pollutants in northern Taiwan.

Conclusions

Our data provided evidences to clinicians, emerging medical services and public health that the ERV risk for OHCA patients is greater at low temperature than at high temperature. Patients with cardio and metabolic disorders need to pay greater attention to low temperature and avoid heat wave.

Advanced vs. Basic Life Support in the Treatment of Out-of-Hospital Cardiopulmonary Arrest in the Resuscitation Outcomes Consortium

BACKGROUND

Prior observational studies suggest no additional benefit from advanced life support (ALS) when compared with providing basic life support (BLS) for patients with out-of-hospital cardiac arrest (OHCA). We compared the association of ALS care with OHCA outcomes using prospective clinical data from the Resuscitation Outcomes Consortium (ROC).

METHODS

Included were consecutive adults OHCA treated by participating emergency medical services (EMS) agencies between June 1, 2011, and June 30, 2015. We defined BLS as receipt of cardiopulmonary resuscitation (CPR) and/or automated defibrillation and ALS as receipt of an advanced airway, manual defibrillation, or intravenous drug therapy. We compared outcomes among patients receiving: 1) BLS-only; 2) BLS + late ALS; 3) BLS + early ALS; and 4) ALS-first care. Using multivariable logistic regression, we evaluated the associations between level of care and return of spontaneous circulation (ROSC), survival to hospital discharge, and survival with good functional status, adjusting for age, sex, witnessed arrest, bystander CPR, shockable initial rhythm, public location, EMS response time, CPR quality, and ROC site.

RESULTS

Among 35,065 patients with OHCA, characteristics were median age 68 years (IQR 56-80), male 63.9%, witnessed arrest 43.8%, bystander CPR 50.6%, and shockable initial rhythm 24.2%. Care delivered was: 4.0% BLS-only, 31.5% BLS + late ALS, 17.2% BLS + early ALS, and 47.3% ALS-first. ALS care with or without initial BLS care was independently associated with increased adjusted ROSC and survival to hospital discharge unless delivered greater than 6 min after BLS arrival (BLS + late ALS). Regardless of when it was delivered, ALS care was not associated with significantly greater functional outcome.

CONCLUSION

ALS care was associated with survival to hospital discharge when provided initially or within six minutes of BLS arrival. ALS care, with or without initial BLS care, was associated with increased ROSC, however it was not associated with functional outcome.

The association of emergency department administration of sodium bicarbonate after out of hospital cardiac arrest with outcomes

BACKGROUND

Sodium bicarbonate administration is mostly restricted to in-hospital use in Taiwan. This study was conducted to investigate the effect of sodium bicarbonate on outcomes among patients with out-of-hospital cardiac arrest (OHCA).

METHODS

This population-based study used a 16-year database to analyze the association between sodium bicarbonate administration for resuscitation in the emergency department (ED) and outcomes. All adult patients with OHCA were identified through diagnostic and procedure codes. The primary outcome was survival to hospital admission and secondary outcome was the rate of death within the first 30days of incidence of cardiac arrest. Cox proportional-hazards regression, logistic regression, and propensity analyses were conducted.

RESULTS

Among 5589 total OHCA patients, 15.1% (844) had survival to hospital admission. For all patients, a positive association was noted between sodium bicarbonate administration during resuscitation in the ED and survival to hospital admission (adjusted odds ratio [OR]: 4.47; 95% confidence interval [CI]: 3.82-5.22, p<0.001). In propensity-matched patients, a positive association was also noted (adjusted OR, 4.61; 95% CI: 3.90-5.46, p<0.001).

CONCLUSIONS

Among patients with OHCA in Taiwan, administration of sodium bicarbonate during ED resuscitation was significantly associated with an increased rate of survival to hospital admission.

Cardiac Arrest Survival in Pediatric and General Emergency Departments

BACKGROUND AND OBJECTIVES

Pediatric out-of-hospital cardiac arrest (OHCA) has a low rate of survival to hospital discharge. Understanding whether pediatric emergency departments (EDs) have higher survival than general EDs may help identify ways to improve care for all patients with OHCA. We sought to determine if OHCA survival differs between pediatric and general EDs.

METHODS

We used the 2009-2014 Nationwide Emergency Department Sample to study children under 18 with cardiac arrest. We compared pediatric EDs (those with >75% pediatric visits) to general EDs on the outcome of survival to hospital discharge or transfer. We determined unadjusted and adjusted survival, accounting for age, region, and injury severity. Analyses were stratified by nontraumatic versus traumatic cause.

RESULTS

The incidences of nontraumatic and traumatic OHCA were 7.91 (95% confidence interval [CI]: 7.52-8.30) and 2.67 (95% CI: 2.49-2.85) per 100 000 person years. In nontraumatic OHCA, unadjusted survival was higher in pediatric EDs than general EDs (33.8% vs 18.9%, P < .001). The adjusted odds ratio of survival in pediatric versus general EDs was 2.2 (95% CI: 1.7-2.8). Children with traumatic OHCA had similar survival in pediatric and general EDs (31.7% vs 26.1%, P = .14; adjusted odds ratio = 1.3 [95% CI: 0.8-2.1]).

CONCLUSIONS

In a nationally representative sample, survival from nontraumatic OHCA was higher in pediatric EDs than general EDs. Survival did not differ in traumatic OHCA. Identifying the features of pediatric ED OHCA care leading to higher survival could be translated into improved survival for children nationally.

Validation of an ICD code for accurately identifying emergency department patients who suffer an out-of-hospital cardiac arrest

AIM

International classification of disease (ICD-9) code 427.5 (cardiac arrest) is utilized to identify cohorts of patients who suffer out-of-hospital cardiac arrest (OHCA), though the use of ICD codes for this purpose has never been formally validated. We sought to validate the utility of ICD-9 code 427.5 by identifying patients admitted from the emergency department (ED) after OHCA.

METHODS

Adult visits to a single ED between January 2007 and July 2012 were retrospectively examined and a keyword search of the electronic medical record (EMR) was used to identify patients. Cardiac arrest was confirmed; and ICD-9 information and location of return of spontaneous circulation (ROSC) were collected. Separately, the EMR was searched for patients who received ICD-9 code 427.5. The kappa coefficient (κ) was calculated, as was the sensitivity and specificity of the code for identifying OHCA.

RESULTS

The keyword search identified 1717 patients, of which 385 suffered OHCA and 333 were assigned the code 427.5. The agreement between ICD-9 code and cardiac arrest was excellent (κ = 0.895). The ICD-9 code 427.5 was both specific (99.4%) and sensitive (86.5%). Of the 52 cardiac arrests that were not identified by ICD-9 code, 33% had ROSC before arrival to the ED. When searching independently on ICD-9 code, 347 patients with ICD-9 code 427.5 were found, of which 320 were "true" arrests. This yielded a positive predictive value of 92% for ICD-9 code 427.5 in predicting OHCA.

CONCLUSIONS

ICD-9 code 427.5 is sensitive and specific for identifying ED patients who suffer OHCA with a positive predictive value of 92%.

Neurostimulant use is associated with improved survival in comatose patients after cardiac arrest regardless of electroencephalographic substrate

AIM

Identify EEG patterns that predict or preclude favorable response in comatose post-arrest patients receiving neurostimulants.

METHODS

We examined a retrospective cohort of consecutive electroencephalography (EEG)-monitored comatose post-arrest patients. We classified the last day of EEG recording before neurostimulant administration based on continuity (continuous/discontinuous), reactivity (yes/no) and malignant patterns (periodic discharges, suppression burst, myoclonic status epilepticus or seizures; yes/no). In subjects who did not receive neurostimulants, we examined the last 24h of available recording. For our primary analysis, we used logistic regression to identify EEG predictors of favorable response to treatment (awakening).

RESULTS

In 585 subjects, mean (SD) age was 57 (17) years and 227 (39%) were female. Forty-seven patients (8%) received a neurostimulant. Neurostimulant administration independently predicted improved survival to hospital discharge in the overall cohort (adjusted odds ratio (aOR) 4.00, 95% CI 1.68-9.52) although functionally favorable survival did not differ. No EEG characteristic predicted favorable response to neurostimulants. In each subgroup of unfavorable EEG characteristics, neurostimulants were associated with increased survival to hospital discharge (discontinuous background: 44% vs 7%, P=0.004; non-reactive background: 56% vs 6%, P<0.001; malignant patterns: 63% vs 5%, P<0.001).

CONCLUSION

EEG patterns described as ominous after cardiac arrest did not preclude survival or awakening after neurostimulant administration. These data are limited by their observational nature and potential for selection bias, but suggest that EEG patterns alone should not affect consideration of neurostimulant use.

Challenges of Using Probabilistic Linkage Methodology to Characterize Post-Cardiac Arrest Care in Michigan

BACKGROUND

To improve survival of patients resuscitated from out of hospital cardiac arrest (OCHA), data is needed to assess and improve inpatient post-resuscitation care. Our objective was to apply probabilistic linkage methodology to link EMS and inpatient databases and evaluate whether it may be used to describe post-arrest care in Michigan.

METHODS

We performed a retrospective study to describe post-cardiac arrest care in adult OHCA patients who were transported to Michigan hospitals from July 1, 2010, to June 30, 2013. Using probabilistic linkage methodology we linked two databases, the Michigan EMS Information System (MI_EMSIS) and the Michigan Inpatient Database (MIDB), which describes inpatient care and outcome of all admissions. Rates of case incidence and survival were compared to published literature. We compared the linked dataset to existing cardiac arrest databases from three counties to evaluate the quality of this linkage.

RESULTS

Multiple iterations of match strategies were used to create a linked EMS-inpatient dataset. There were 12,838 MI_EMSIS cardiac arrest records of which 1,977 were matched with MIDB records, identifying them as surviving to hospital admission. Of these 590 (30.0%) survived to hospital discharge. The annual survival incidence/100,000 population to admission was 6.93/100,000 and survival incidence to discharge was 2.1/100,000. The matched dataset was compared to county databases identified a limited sensitivity [48.2%, 95% CI 42.1%-55.3%)] and positive predictive value [64.4%, 95% CI 56.8%-71.3%)].

CONCLUSION

Use of the MI_EMSISEMS database and the Michigan Inpatient database was feasible and produced rates of cardiac arrest admission and survival rates similar to published literature. This process yielded a limited match compared to existing county cardiac arrest databases. We conclude that such a linked dataset is useful for descriptive purposes but not as a population based dataset to evaluate statewide post-cardiac arrest care.

Cardiac arrest risk standardization using administrative data compared to registry data

BACKGROUND

Methods for comparing hospitals regarding cardiac arrest (CA) outcomes, vital for improving resuscitation performance, rely on data collected by cardiac arrest registries. However, most CA patients are treated at hospitals that do not participate in such registries. This study aimed to determine whether CA risk standardization modeling based on administrative data could perform as well as that based on registry data.

METHODS AND RESULTS

Two risk standardization logistic regression models were developed using 2453 patients treated from 2000-2015 at three hospitals in an academic health system. Registry and administrative data were accessed for all patients. The outcome was death at hospital discharge. The registry model was considered the "gold standard" with which to compare the administrative model, using metrics including comparing areas under the curve, calibration curves, and Bland-Altman plots. The administrative risk standardization model had a c-statistic of 0.891 (95% CI: 0.876-0.905) compared to a registry c-statistic of 0.907 (95% CI: 0.895-0.919). When limited to only non-modifiable factors, the administrative model had a c-statistic of 0.818 (95% CI: 0.799-0.838) compared to a registry c-statistic of 0.810 (95% CI: 0.788-0.831). All models were well-calibrated. There was no significant difference between c-statistics of the models, providing evidence that valid risk standardization can be performed using administrative data.

CONCLUSIONS

Risk standardization using administrative data performs comparably to standardization using registry data. This methodology represents a new tool that can enable opportunities to compare hospital performance in specific hospital systems or across the entire US in terms of survival after CA.

Variations in survival after cardiac arrest among academic medical center-affiliated hospitals

Background

Variation exists in cardiac arrest (CA) survival among institutions. We sought to determine institutional-level characteristics of academic medical centers (AMCs) associated with CA survival.

Methods

We examined discharge data from AMCs participating with Vizient clinical database–resource manager. We identified cases using ICD-9 diagnosis code 427.5 (CA) or procedure code 99.60 (CPR). We estimated hospital-specific risk-standardized survival rates (RSSRs) using mixed effects logistic regression, adjusting for individual mortality risk. Institutional and community characteristics of AMCs with higher than average survival were compared with those with lower survival.

Results

We analyzed data on 3,686,296 discharges in 2012, of which 33,700 (0.91%) included a CA diagnosis. Overall survival was 42.3% (95% CI 41.8–42.9) with median institutional RSSR of 42.6% (IQR 35.7–51.0; Min-Max 19.4–101.6). We identified 28 AMCs with above average survival (median RSSR 61.8%) and 20 AMCs with below average survival (median RSSR 26.8%). Compared to AMCs with below average survival, those with high CA survival had higher CA volume (median 262 vs.119 discharges, p = 0.002), total beds (722 vs. 452, p = 0.02), and annual surgical volume (24,939 vs. 13,109, p<0.001), more likely to offer cardiac catheterization (100% vs. 72%, p = 0.007) or cardiac surgery (93% vs. 61%, p = 0.02) and cared for catchment areas with higher household income ($61,922 vs. $49,104, p = 0.004) and lower poverty rates (14.6% vs. 17.3%, p = 0.03).

Conclusion

Using discharge data from Vizient, we showed AMCs with higher CA and surgical case volume, cardiac catheterization and cardiac surgery facilities, and catchment areas with higher socioeconomic status had higher risk-standardized CA survival.

Utilization of electroencephalogram post cardiac arrest in the United States: A nationwide retrospective cohort analysis

OBJECTIVE

The use of electroencephalogram (EEG) has been demonstrated to have diagnostic and prognostic value in cardiac arrest patients. The use of this modality across the United States in this population is unknown.

METHODS

The Nationwide Inpatient Sample (NIS) is a federal database capturing 20% of all US hospital admissions. A cohort of patients who suffered both in and out of hospital cardiac arrests from the 2006 to 2012 NIS datasets was created.

RESULTS

The records of 55,208,382 hospitalizations were analyzed, of which 207,703 patients suffered a cardiac arrest. There were 2952 (1.42%) patients who also had an EEG. Patients who had an EEG compared to those who did not were: younger (62.2 years SD 16.6 vs 66.9 years SD 16.2, p<0.01), were less likely to have insurance coverage (89.9% vs 91.6%, p=0.03) and had significantly longer length of stay (8.6days IQR 3.7-17.1 vs 4.1days IQR 1.0-10.5, p<0.01). Patients treated at urban teaching hospitals were more likely to receive an EEG than patients treated at urban non-teaching and rural hospitals (p<0.01). The rate of EEG in survivors of cardiac arrest increased from 1.03% in 2006 to 2.16% in 2012, a relative increase of 110% (p<0.02). The median time to performance of an EEG was 1.6days IQR 0.33-4.53 days.

CONCLUSION

EEG is performed on approximately 2% of patients who suffer cardiac arrest in the United States. The treatment hospital and patient characteristics of those who received an EEG different from those who did not.

Long-term survival benefit from treatment at a specialty center after cardiac arrest

INTRODUCTION

The Institute of Medicine and American Heart Association have called for tiered accreditation standards and regionalization of post-cardiac arrest care, but there is little data to support that regionalization has a durable effect on patient outcomes. We tested the effect of treatment at a high-volume center on long-term outcome after sudden cardiac arrest (SCA).

METHODS

We included patients hospitalized at one of 7 medical centers in Southwestern Pennsylvania after SCA from 2005 to 2013. Centers were one regional referral center with an organized systems for post-SCA care, two moderate volume tertiary care centers and 4 low-volume centers. We abstracted clinical characteristics and outcomes at hospital discharge, and for survivors to discharge we queried the National Death Index for long-term survival data. We used Cox regression to determine the unadjusted associations of baseline predictors and survival, and built an adjusted model controlling for baseline predictors.

RESULTS

Overall, 987 patients survived to discharge. During 2196 person-years of follow-up, median survival was 5.3 years and there were 396 deaths. In unadjusted analysis, treating center, age, arrest location, Charlson Comorbidity Index, initial rhythm, cardiac catheterization, defibrillator placement, discharge disposition, and neurological status at discharge were associated with long-term outcome. In adjusted analysis, treatment at the high-volume cardiac arrest center was associated with improved survival compared to treatment at other centers (hazards ratio 1.49, 95% confidence interval 1.19-1.86).

CONCLUSION

Treatment at a high-volume cardiac arrest center with organized systems for post-arrest care is associated with a substantial long-term survival benefit after hospital discharge.

Impact of Hospital Teaching Status on Mortality, Length of Stay and Cost Among Patients With Cardiac Arrest in the United States

Limited data exist regarding the in-hospital outcomes in patients with cardiac arrest (CA) in teaching versus nonteaching hospital settings. Using the Nationwide (National) Inpatient Sample (2008 to 2012), 731,107 cases of CA were identified using International Classification of Diseases, Ninth Edition codes. Among these patients, 348,368 (47.6%) were managed in teaching hospitals and 376,035 (51.4%) in nonteaching hospitals. Patients in teaching hospitals with CA were younger (62.42 vs 68.08 years old), had less co-morbidities (p <0.001), were less likely to be white (54.6% vs 65.5%) and more likely to be uninsured (9.1% vs 7.6%). Mortality in patients with CA was significantly lower in teaching hospitals than in nonteaching hospitals (55.3% vs 58.8%; all p <0.001). The mortality remained significantly lower after adjusting for baseline patient and hospital characteristics (odds ratio 0.917, CI 0.899 to 0.937, p <0.001). However, the survival benefit was no longer present after adjusting for in-hospital procedures (OR 0.997, CI 0.974 to 1.02, p = 0.779). In conclusion, teaching status of the hospital was associated with decreased in-hospital mortality in patients with CA. The differences in mortality disappeared after adjusting for in-hospital procedures, indicating that routine application of novel therapeutic methods in patients with CA in teaching hospitals could translate into improved survival outcomes.