Initial Cardiac Arrest Rhythm Research Articles

The Interaction Effect of Age, Initial Rhythm, and Location on Outcomes After Out-of-Hospital Cardiac Arrest: A Retrospective Cohort Study

Background: Out-of-hospital cardiac arrest (OHCA) is a critical global health challenge and a leading cause of mortality. This study investigates the combined effect of initial cardiac arrest rhythm, patient age, and location on the return of spontaneous circulation (ROSC) in OHCA patients. Methods: This retrospective study analyzed medical records from the National Emergency Medical Service (EMS) in Poland between January 2021 and June 2022. Data from 33,636 patients with OHCA who received cardiopulmonary resuscitation (CPR) at the scene were included. Results: Public incidents were associated with higher ROSC rates (54.10% vs. 31.53%, p < 0.001). Initial shockable rhythms (VF/pVT) significantly increased the odds of ROSC (OR = 3.74, 95% CI 3.39–4.13, p < 0.001). Obesity decreased the odds of ROSC in at-home cases (OR = 0.85, 95% CI 0.73–0.99, p = 0.036) but had no significant effect in public cases. The effect of age on ROSC outcomes varied significantly depending on the location. In patients younger than 60 years, better ROSC outcomes were observed in at-home cases, while for those older than 60 years, the odds of ROSC were higher in public locations. Each additional year of age decreased the odds of ROSC by 1.62% in at-home incidents (p < 0.001) and by 0.40% in public incidents (p = 0.009). Sex differences were significant in public locations, with women having higher odds of ROSC compared to men (OR = 0.57, 95% CI 0.37–0.87, p = 0.009 for VF/pVT). Conclusions: The interaction between the location of OHCA, initial cardiac rhythm, and patient age significantly impacts ROSC outcomes. Public locations show higher ROSC rates, especially in cases with shockable rhythms (VF/pVT). Age modifies ROSC outcomes, with younger patients benefiting more at home, and older patients showing better outcomes in public places.

Evaluation of cardiopulmonary resuscitation for patient outcomes in Imam Reza General Hospital Tabriz, Iran

Introduction: Cardiopulmonary resuscitation (CPR) is a life-saving procedure for patients experiencing cardiac arrest. The success rate of in-hospital arrests varies from 2% to 27% according to different studies. Aim of our study was an investigation on in-hospital cardiac arrest in a tertiary hospital in north-west of Iran. Methods: We included all in-hospital cardiac arrests over a three-month period of time. Data related to age and sex of patients, cause of hospitalization, length of stay, cause of cardiac arrest, and outcome of CPR has been studied. Results: Sixty-six patients with cardiac arrest were recorded. Mean age was 62.59 (±20.7) years. Cardiovascular disease, neurological diseases, and lung diseases were the most common causes of hospitalization. The median length of hospitalization prior to arrest was seven days. CPR was initiated within 30 seconds of arrest detection in all cases. The initial cardiac arrest rhythm was asystole in majority of cases (80.3%) followed by ventricular tachycardia in 10.6 % and pulseless electrical activity (PEA) in 9.1% of cases. Five patients could survive to discharge in which two patients had a good neurologic outcome. Conclusion: This study indicates that in-hospital cardiac arrest has a poor prognosis, with asystole being the most prevalent initial rhythm.

Abstract 339: Causes and Initial Cardiac Arrest Rhythms in a National Paediatric Cohort From Norway

Background: Mortality following paediatric out-of-hospital cardiac arrest (POHCA) is high. Registration of any resuscitation attempt is mandated by law in the Norwegian Cardiac Arrest Registry (NorCAR), providing an opportunity to study precipitating causes from a nationwide population perspective. Research questions and aims The study set out to investigate the precipitating causes and the presenting rhythms of OHCA in children; enabling a focused approach to prevention and treatment of cardiac arrest in children. Methods: NorCAR data for children aged 0-17 years was extracted for 2016-21. Cases of perinatal resuscitation and children not receiving ongoing cardiopulmonary resuscitation by ambulance personnel were excluded. Descriptive statistics were used to create age-stratified summaries for presumed causes of POCHA and presenting rhythms. Results: In total, 308 children were included. Presumed causes of cardiac arrest included choking (n=67), cardiac aetiology (n=55), respiratory failure (n=51), sudden infant death syndrome (n=51), and drowning (n=37). The presumed causes differed substantially according to age (Figure). Non-shockable rhythms dominated (87%, 250 of 287 with available rhythm data). The proportion of shockable rhythms increased with age to 15 % (19 of 127) in the 13-17 year age group. Conclusion: The causes of POHCA were diverse and highly age dependent. This knowledge may inform both parents and caretakers, health professionals, and the whole community with respect to effective prevention, proper first aid, and focused emergency medical treatment.

Prevalence and factors associated with initial and subsequent shockable cardiac arrest rhythms and their association with patient outcomes in dogs and cats undergoing cardiopulmonary resuscitation: A RECOVER registry study.

To report the prevalence of initial shockable cardiac arrest rhythms (I-SHKR), incidence of subsequent shockable cardiac arrest rhythms (S-SHKR), and factors associated with I-SHKRs and S-SHKRs and explore their association with return of spontaneous circulation (ROSC) rates in dogs and cats undergoing CPR. Multi-institutional prospective case series from 2016 to 2021, retrospectively analyzed. Eight university and eight private practice veterinary hospitals. A total of 457 dogs and 170 cats with recorded cardiac arrest rhythm and event outcome reported in the Reassessment Campaign on Veterinary Resuscitation CPR registry. Logistic regression was used to evaluate association of animal, hospital, and arrest variables with I-SHKRs and S-SHKRs and with patient outcomes. Odds ratios (ORs) were generated, and significance was set at P<0.05. Of 627 animals included, 28 (4%) had I-SHKRs. Odds for I-SHKRs were significantly higher in animals with a metabolic cause of arrest (OR 7.61) and that received lidocaine (OR 17.50) or amiodarone (OR 21.22) and significantly lower in animals experiencing arrest during daytime hours (OR 0.22), in the ICU (OR 0.27), in the emergency room (OR 0.13), and out of hospital (OR 0.18) and that received epinephrine (OR 0.19). Of 599 initial nonshockable rhythms, 74 (12%) developed S-SHKRs. Odds for S-SHKRs were significantly higher in animals with higher body weight (OR 1.03), hemorrhage (OR 2.85), or intracranial cause of arrest (OR 3.73) and that received epinephrine (OR 11.36) or lidocaine (OR 18.72) and significantly decreased in those arresting in ICU (OR 0.27), emergency room (OR 0.29), and out of hospital (OR 0.38). Overall, 171 (27%) animals achieved ROSC, 81 (13%) achieved sustained ROSC, and 15 (2%) survived. Neither I-SHKRs nor S-SHKRs were significantly associated with ROSC. I-SHKRs and S-SHKRs occur infrequently in dogs and cats undergoing CPR and are not associated with increased ROSC rates.

Pulseless electrical activity and asystole during in-hospital cardiac arrest: Disentangling the ‘nonshockable’ rhythms

BackgroundPulseless electrical activity (PEA) and asystole account for 81% of initial in-hospital cardiac arrest (IHCA) rhythms in the U.S.A. These “non-shockable” rhythms are often grouped together in resuscitation research and practice. We hypothesized that PEA and asystole are distinct initial IHCA rhythms with distinguishing features. MethodsThis was an observational cohort study using the prospectively collected nationwide Get With The Guidelines®-Resuscitation registry. Adult patients with an index IHCA and an initial rhythm of PEA or asystole between the years of 2006 and 2019 were included. Patients with PEA vs. asystole were compared with respect to pre-arrest characteristics, resuscitation practice, and outcomes. ResultsWe identified 147,377 (64.9%) PEA and 79,720 (35.1%) asystolic IHCA. Asystole had more arrests in non-telemetry wards (20,530/147,377 [13.9%] PEA vs. 17,618/79,720 [22.1%] asystole). Asystole had 3% lower adjusted odds of ROSC (91,007 [61.8%] PEA vs. 44,957 [56.4%] asystole, aOR 0.97, 95%CI 0.96–0.97, P < 0.01); there was no statistically significant difference in survival to discharge (28,075 [19.1%] PEA vs. 14,891 [18.7%] asystole, aOR 1.00, 95%CI 1.00–1.01, P = 0.63). Duration of resuscitation for those without ROSC were shorter for asystole (29.8 [±22.5] minutes in PEA vs. 26.2 [±21.5] minutes in asystole, adjusted mean difference −3.05 95%CI -3.36–-2.74, P < 0.01). InterpretationPatients suffering IHCA with an initial PEA rhythm had patient and resuscitation level differences from those with asystole. PEA arrests were more common in monitored settings and received longer resuscitations. Even though PEA was associated with higher rates of ROSC, there was no difference in survival to discharge.

Abstract 12: Identifying Emergency Medical Service Agencies In Black And Hispanic Communities With High Cardiac Arrest Survival Rates

Background: Black and Hispanic individuals have lower survival rates for out-of-hospital cardiac arrest (OHCA). Whether there are Emergency Medical Service (EMS) agencies in Black and Hispanic communities with high survival rates for OHCA is unknown but critical to identifying strategies to reduce racial and ethnic disparities in OHCA survival. Methods: Within the Cardiac Arrest Registry to Enhance Survival, we identified adults with non-traumatic OHCA during 2015-2019. EMS agencies were categorized as working in Black/Hispanic communities if &gt;50% of residents in their catchment area were Black or Hispanic. Using hierarchical logistic regression, we calculated risk-standardized survival rates (RSSR) to hospital admission for OHCA in each EMS agency, adjusted for patients’ age, sex, witnessed arrest status, presumed arrest etiology, initial cardiac arrest rhythm, and arrest location. We then examined the distribution of EMS agencies that work in Black/Hispanic communities across quartiles of OHCA survival. Results: Among 764 EMS agencies (258,342 OHCAs), the median RSSR was 27.4% with an absolute difference of &gt;10% across quartiles (median 22.4% in the lowest vs. 32.9% in the highest quartile; 191 EMS agencies in each quartile). There were 82 EMS agencies working in Black/Hispanic communities overall, with 26 (31.7%) in the lowest RSSR quartile and 15 (18.3%) in the highest. After further adjustment for agency-level rates of bystander CPR, EMS response time and termination of resuscitation practices, there remained 29 (35.4%) EMS agencies in the lowest RSSR quartile and 16 (19.5%) in the highest. Conclusion: EMS agencies working in Black and Hispanic communities have lower prehospital survival for OHCA, although high-performing agencies exist. Identifying best practices at EMS agencies with the highest prehospital survival rates, particularly among agencies serving Black and Hispanic communities, has the potential to improve overall OHCA survival and reduce existing survival disparities.

Survival outcomes and resuscitation process measures in maternal in-hospital cardiac arrest

Maternal in-hospital cardiac arrest is a rare event with the potential for resuscitation treatment delays because of the difficulty accessing hospital obstetrical units and limited simulation training or resuscitation experience of obstetrical staff. However, it is unclear whether survival rates and processes of care differ between women with a maternal in-hospital cardiac arrest and those with a nonmaternal in-hospital cardiac arrest. We aimed determine whether to there are delays in process measures and differences in survival outcomes between pregnant and nonpregnant women who have in-hospital cardiac arrest. Using data from 2000 to 2019 in the Get With The Guidelines-Resuscitation registry, we compared resuscitation outcomes between women aged 18 to 50 years with a maternal or nonmaternal in-hospital cardiac arrest. Using a nonparsimonious propensity score, we matched patients with a maternal in-hospital cardiac arrest to as many as 10 women with a nonmaternal in-hospital cardiac arrest. We constructed conditional logistic regression models to compare survival outcomes (survival to discharge, favorable neurologic survival [discharge cerebral performance score of 1], and return of spontaneous circulation) and processes of care (delayed defibrillation [>2 minutes] and administration of epinephrine [>5 minutes]) between women with a maternal in-hospital cardiac arrest vs those with a nonmaternal in-hospital cardiac arrest. Overall, 421 women with a maternal in-hospital cardiac arrest were matched by propensity score to 2316 women with a nonmaternal in-hospital cardiac arrest. The mean age among propensity score-matched women with a maternal in-hospital cardiac arrest was 31.4 (standard deviation, 6.5) years, where 33.7% were of Black race and 86.9% had an initial nonshockable cardiac arrest rhythm. Unadjusted survival rates were higher in women with a maternal in-hospital cardiac arrest than in women with a nonmaternal in-hospital cardiac arrest: survival to discharge of 45.1% vs 26.5%, survival with cerebral performance category 1 status of 36.1% vs 17.7%, and return of spontaneous circulation of 75.8% vs 70.6%. After adjustment, there was no difference in the likelihood of survival to discharge (odds ratio, 1.19; 95% confidence interval, 0.82-1.73) or return of spontaneous circulation (odds ratio, 0.94; 95% confidence interval, 0.65-1.35) between women with a maternal in-hospital cardiac arrest and those with a nonmaternal in-hospital cardiac arrest. However, women with a maternal in-hospital cardiac arrest were more likely to have favorable neurologic survival (odds ratio, 1.57; 95% confidence interval, 1.06-2.33). Compared with women with a nonmaternal in-hospital cardiac arrest, women with a maternal in-hospital cardiac arrest had similar rates of delayed defibrillation (42.5% vs 34.4%; odds ratio, 1.14 [95% confidence interval, 0.41-3.18]; P=.31) and delayed administration of epinephrine (13.8% vs 10.6%; odds ratio, 0.96 [95% confidence interval, 0.50-1.86]; P=.09). Although concerns have been raised about resuscitation outcomes in women with a maternal in-hospital cardiac arrest, the rates of survival and resuscitation processes of care were not worse in women with a maternal in-hospital cardiac arrest.

Comparison of Machine Learning Methods for Predicting Outcomes After In-Hospital Cardiac Arrest.

Prognostication of neurologic status among survivors of in-hospital cardiac arrests remains a challenging task for physicians. Although models such as the Cardiac Arrest Survival Post-Resuscitation In-hospital score are useful for predicting neurologic outcomes, they were developed using traditional statistical techniques. In this study, we derive and compare the performance of several machine learning models with each other and with the Cardiac Arrest Survival Post-Resuscitation In-hospital score for predicting the likelihood of favorable neurologic outcomes among survivors of resuscitation. Analysis of the Get With The Guidelines-Resuscitation registry. Seven-hundred fifty-five hospitals participating in Get With The Guidelines-Resuscitation from January 1, 2001, to January 28, 2017. Adult in-hospital cardiac arrest survivors. None. Of 117,674 patients in our cohort, 28,409 (24%) had a favorable neurologic outcome, as defined as survival with a Cerebral Performance Category score of less than or equal to 2 at discharge. Using patient characteristics, pre-existing conditions, prearrest interventions, and periarrest variables, we constructed logistic regression, support vector machines, random forests, gradient boosted machines, and neural network machine learning models to predict favorable neurologic outcome. Events prior to October 20, 2009, were used for model derivation, and all subsequent events were used for validation. The gradient boosted machine predicted favorable neurologic status at discharge significantly better than the Cardiac Arrest Survival Post-Resuscitation In-hospital score (C-statistic: 0.81 vs 0.73; p < 0.001) and outperformed all other machine learning models in terms of discrimination, calibration, and accuracy measures. Variables that were consistently most important for prediction across all models were duration of arrest, initial cardiac arrest rhythm, admission Cerebral Performance Category score, and age. The gradient boosted machine algorithm was the most accurate for predicting favorable neurologic outcomes in in-hospital cardiac arrest survivors. Our results highlight the utility of machine learning for predicting neurologic outcomes in resuscitated patients.

Parada cardiorrespiratória no atendimento pré-hospitalar

Cross-sectional research with a descriptive design of a quantitative analytical approach, carried out between 2018 and 2019, using forms with registration completed by the care teams of the Advanced Support Units of Sao Jose do Rio Preto, SP, Brazil, in order to analyze the outcomes of cardiac arrest in patients in pre-hospital care. The collected and tabulated data were analyzed statistically in a descriptive and inferential manner. 291 attendance records were considered. Of the outcomes of cardiorespiratory arrest, deaths were reached in 63.92%, deaths during care in 30.24% and PCR reversed and referral to the hospital in 5.84%. The factors that most influenced deaths were: advanced age (66.66% over 71 years old), occurrence at residences (75.81%) and cardiovascular diseases (74.91%). The response time was significant in the outcome of death, as well as the initial rhythm of asystole (in 99.46% of the death reports and 70.45% of the deaths during care). The ambulance arrived at the site in 12 minutes in 76.47% of the cases. Of the reversed cardiorespiratory arrest, cardiopulmonary resuscitation was being performed (64.71%) before the Advanced Support Unit arrived. The training of the community in relation to the early recognition of cardiopulmonary arrest and the performance of cardiopulmonary resuscitation is important.

Pulseless Electrical Activity as the Initial Cardiac Arrest Rhythm: Importance of Preexisting Left Ventricular Function.

BackgroundPulseless electrical activity (PEA) is a common initial rhythm in cardiac arrest. A substantial number of PEA arrests are caused by coronary ischemia in the setting of acute coronary occlusion, but the underlying mechanism is not well understood. We hypothesized that the initial rhythm in patients with acute coronary occlusion is more likely to be PEA than ventricular fibrillation in those with prearrest severe left ventricular dysfunction.Methods and ResultsWe studied the initial cardiac arrest rhythm induced by acute left anterior descending coronary occlusion in swine without and with preexisting severe left ventricular dysfunction induced by prior infarcts in non–left anterior descending coronary territories. Balloon occlusion resulted in ventricular fibrillation in 18 of 34 naïve animals, occurring 23.5±9.0 minutes following occlusion, and PEA in 1 animal. However, all 18 animals with severe prearrest left ventricular dysfunction (ejection fraction 15±5%) developed PEA 1.7±1.1 minutes after occlusion.ConclusionsAcute coronary ischemia in the setting of severe left ventricular dysfunction produces PEA because of acute pump failure, which occurs almost immediately after coronary occlusion. After the onset of coronary ischemia, PEA occurred significantly earlier than ventricular fibrillation (<2 minutes versus 20 minutes). These findings support the notion that patients with baseline left ventricular dysfunction and suspected coronary disease who develop PEA should be evaluated for acute coronary occlusion.

Identifying prognostic factors and developing accurate outcome predictions for in-hospital cardiac arrest by using artificial neural networks

BackgroundAccurate estimation of neurological outcomes after in-hospital cardiac arrest (IHCA) provides crucial information for clinical management. This study used artificial neural networks (ANNs) to determine the prognostic factors and develop prediction models for IHCA based on immediate preresuscitation parameters. MethodsThe derived cohort comprised 796 patients with IHCA between 2006 and 2014. We applied ANNs to develop prediction models and evaluated the significance of each parameter associated with favorable neurological outcomes. An independent dataset of 108 IHCA patients receiving targeted temperature management was used to validate the identified parameters. The generalizability of the models was assessed through fivefold cross-validation. The performance of the models was assessed using the area under the curve (AUC). ResultsANN model 1, based on 19 baseline parameters, and model 2, based on 11 prearrest parameters, achieved validation AUCs of 0.978 and 0.947, respectively. ANN model 3 based on 30 baseline and prearrest parameters achieved an AUC of 0.997. The key factors associated with favorable outcomes were the duration of cardiopulmonary resuscitation; initial cardiac arrest rhythm; arrest location; and whether the patient had a malignant disease, pneumonia, and respiratory insufficiency. On the basis of these parameters, the validation performance of the ANN models achieved an AUC of 0.906 for IHCA patients who received targeted temperature management. ConclusionThe ANN models achieved highly accurate and reliable performance for predicting the neurological outcomes of successfully resuscitated patients with IHCA. These models can be of significant clinical value in assisting with decision-making, especially regarding optimal postresuscitation strategies.

Long-term survival among OHCA patients who survive to 30 days: Does initial arrest rhythm remain a prognostic determinant?

ObjectiveTo determine whether initial cardiac arrest rhythm remains a prognostic determinant in longer term OHCA survival. MethodsThe St John Western Australian OHCA database was used to identify adults who survived for at least 30 days after an OHCA of presumed medical aetiology, in the Perth metropolitan area between 1998 and 2017. Associations between 8-year OHCA survival and variables of interest were analysed using a Multi-Resolution Hazard (MRH) estimator model with 1-year intervals. ResultsOf the 871 OHCA patients who survived 30 days, 718 (82%) presented with a shockable initial arrest rhythm and 153 (18%) presented with a non-shockable rhythm. Compared to patients with initial shockable arrests, patients with non-shockable arrests experienced increased mortality in the first (HR 3.33, 95% CI 2.12−5.32), second (HR 2.58, 95% CI 1.22−5.15), third (HR 2.21, 95% CI 1.02−4.42) and fourth (HR 2.21, 95% CI 1.02−4.42) year post arrest; however, in subsequent years the initial arrest rhythm ceased to be significantly associated with survival. The overall 8-year survival estimates after adjustment for peri-arrest factors (as potential confounders) were 87% (95% CI 77–93%) for shockable arrests and 73% (95% CI 55–86%) for non-shockable arrests. ConclusionsPatients with non-shockable (as opposed to shockable) initial arrest rhythms experienced higher mortality in the first 4-years following their OHCA; however, after four years the initial arrest rhythm ceased to be associated with survival.

Can We Predict Good Survival Outcomes by Classifying Initial and Re-Arrest Rhythm Change Patterns in Out-of-Hospital Cardiac Arrest Settings?

ObjectiveThe purpose of this study was to investigate whether a change in prehospital arrest rhythms could allow medical personnel to predict survival outcomes in patients who achieved a return of spontaneous circulation (ROSC) in the setting of out-of-hospital cardiac arrest (OHCA).MethodsThe design of this study was retrospective, multi-regional, observational, and cross-sectional with a determining period between August 2015 and July 2016. Cardiac arrest rhythms were defined as a shockable rhythm (S), which refers to ventricular fibrillation (VF) or pulseless ventricular tachycardia (pVT), and non-shockable rhythm (NS), which refers to pulseless electrical activity or asystole. Survival to admission, survival to discharge, and good cerebral performance category (CPC) (CPC 1 or 2) were defined as good survival outcomes.ResultsA total of 163 subjects were classified into four groups according to the rhythm change pattern: NS→NS (98), S→S (27), S→NS (23), and NS→S (15). NS→NS pattern was used as the reference in logistic regression analysis. In the case of survival to hospital admission, the odds ratio (OR) (95% CI) of the S→S pattern was the highest [12.63 (3.56-44.85), p: <0.001 by no correction] and [7.29 (1.96-27.10), p = 0.003 with adjusting]. In the case of survival to hospital discharge, the OR (95% CI) of the S→S pattern was the highest [37.14 (11.71-117.78), p: <0.001 by no correction] and [13.85 (3.69-51.97), p: <0.001 with adjusting]. In the case of good CPC (CPC 1 or 2) at discharge, the OR (95% CI) of the S→S pattern was the highest [96 (19.14-481.60), p: <0.001 by no correction] and [149.69 (19.51-1148.48), p: <0.001 with adjusting].ConclusionsThe S→S group showed the highest correlation with survival to hospital admission, survival to hospital discharge, and good CPC (CPC 1 or 2) at discharge compared to the NS→NS group. Verifying changes in initial cardiac arrest rhythm and prehospital re-arrest (RA) rhythm patterns after prehospital ROSC can help us predict good survival outcomes in the OHCA setting.

In-Hospital vs. Out-of-Hospital Cardiac Arrest: Patient Characteristics and Survival

BackgroundCardiac arrests are often categorized into two separate groups depending on the location of the arrest: in-hospital cardiac arrest (IHCA) and out-of-hospital cardiac arrest (OHCA). Despite this distinction, few studies have compared the two groups directly. The aim of this study was to compare patient characteristics, cardiac arrest characteristics, and outcomes for IHCA and OHCA patients. MethodsData on IHCA and OHCA in Denmark were obtained from two nationwide, prospective registries. All adult (≥18 years old) patients with index IHCA or OHCA from January 1, 2017 to December 31, 2018 were included. Supplementary information on outcomes, hospitalizations, and chronic diseases came from additional national registries. The primary outcome was 30-day survival and secondary outcomes were return of spontaneous circulation (ROSC) and 1-year survival. ResultsThe study included 3501 patients with IHCA and 8846 patients with OHCA. The two groups were similar in demographics, most comorbidities, and initial cardiac arrest rhythm. In the unadjusted analysis, IHCA was associated with increased survival to 30 days compared to OHCA (risk ratio [RR] = 1.41; 95% CI, 1.30; 1.54) and 1 year (RR = 1.46; 95% CI, 1.33; 1.61). Adjusting for age, sex, and comorbidities did not change the RR substantially. When cardiac arrest characteristics were added to the model, the RR decreased from 1.51 (95% CI, 1.39; 1.65) to 1.06 (95% CI, 0.93; 1.20) for survival to 30 days and from 1.66 (95% CI, 1.50; 1.84) to 1.09 (95% CI, 0.94; 1.26) for survival to 1 year. In all subgroup analyses based on cardiac arrest characteristics (e.g. witnessed status), the association between location and outcome was substantially mitigated compared to the primary analyses. ConclusionsIn this large, national study, we found that IHCA and OHCA patients were remarkably similar in demographics and most comorbidities. IHCA patients had better outcomes compared to OHCA patients, although these differences disappeared when comparing patients with similar cardiac arrest characteristics.

Abstract 235: The Covid-19 Pandemic in Dallas: Increased Out-of-hospital Cardiac Arrest and Death

Introduction: Since March, the CDC has reported weekly excess deaths of up to 40% in the US. Spikes in excess deaths were associated with spikes in COVID-19 cases. In Texas, 55% of excess deaths from March 1 to May 30, 2020 were unattributed to COVID-19. One possible source of this unaccounted excess death is out-of-hospital cardiac arrest, which corresponds to a notable decline in hospitalizations for acute cardiovascular events. Objective: To compare the number of out-of-hospital cardiac arrest (OOHCA) and dead-on-scene cases in Dallas, Texas in years prior to and during the COVID-19 pandemic. Methods: The Dallas-Fort Worth Center for Resuscitation Research Cardiac Arrest Registry provided data for this IRB-approved study. Eligible cases were non-traumatic OOHCAs who received cardiopulmonary resuscitation (CPR) from emergency medical services (EMS) providers. We compared monthly case numbers in 2017, 2018, and 2019 with case numbers in 2020 at the time of the COVID-19 pandemic in Dallas, TX. Additionally, we compared the numbers of non-traumatic deaths (declared dead on scene without receiving CPR from EMS providers) in the same timeframes. Results: While total counts of out-of-hospital cardiac arrest during the months of March to June decreased from 2017 to 2019 by 9.2% and 1.2% respectively, the number of cardiac arrest cases rose dramatically by 47.9% in 2020 (p &lt; 0.05).(Table) The percentage of OOHCAs with an initial rhythm of asystole increased as well, from 50.1% in 2018 and 2019 to 60.4% in 2020. The total number of dead-on-scene cases was also higher in March to June 2020 than in 2017 to 2019 (NS). Conclusion: Increased out-of-hospital cardiac arrest is likely contributing to the unattributed excess deaths noted during the months of the COVID-19 pandemic in Dallas, TX. The rise in cases may be indirectly attributable to COVID-19 as cardiovascular events go untreated or treated too late.

Cardiac Arrest Due to Hypocalcemia

Fifty-nine-year-old male patient had a sudden cardiac arrest (CA) while waiting for his appointment at the urology outpatient clinic. The local staff and the rapid response team (RRT) promptly started cardiopulmonary resuscitation maneuvers. Initial CA rhythm was ventricular fibrillation (VF) and the collapse-shock interval was five minutes. Return of spontaneous circulation (ROSC) occurred on the following cycle, comprising six minutes of arrest. There was not enough time to administer epinephrine or any other drugs. After ROSC, a definitive airway was [...]

Association of Hospital-Level Acute Resuscitation and Postresuscitation Survival With Overall Risk-Standardized Survival to Discharge for In-Hospital Cardiac Arrest

Survival after in-hospital cardiac arrest depends on 2 distinct phases: responsiveness and quality of the hospital code team (ie, acute resuscitation phase) and intensive and specialty care expertise (ie, postresuscitation phase). Understanding the association of these 2 phases with overall survival has implications for design of in-hospital cardiac arrest quality measures. To determine whether hospital-level rates of acute resuscitation survival and postresuscitation survival are associated with overall risk-standardized survival to discharge for in-hospital cardiac arrest. This observational cohort study included 86 426 patients with in-hospital cardiac arrest from January 1, 2015, through December 31, 2018, recruited from 290 hospitals participating in the Get With The Guidelines-Resuscitation registry. Risk-adjusted rates of acute resuscitation survival, defined as return of spontaneous circulation for at least 20 minutes, and postresuscitation survival, defined as survival to discharge among patients achieving return of spontaneous circulation. The primary outcome was overall risk-standardized survival rate (RSSR) for in-hospital cardiac arrest calculated using a previously validated model. The correlation between a hospital's overall RSSR and risk-adjusted rates of acute resuscitation and postresuscitation survival were examined. Of 86 426 patients with in-hospital cardiac arrest, the median age was 67.0 years (interquartile range [IQR], 56.0-76.0 years); 50 665 (58.6%) were men, and 71 811 (83.1%) had an initial nonshockable cardiac arrest rhythm. The median RSSR was 25.1% (IQR, 21.9%-27.7%). The median risk-adjusted acute resuscitation survival was 72.4% (IQR, 67.9%-76.9%), and risk-adjusted postresuscitation survival was 34.0% (IQR, 31.5%-37.7%). Although a hospital's RSSR was correlated with survival during both phases, the correlation with postresuscitation survival (ρ, 0.90; P < .001) was stronger compared with the correlation with acute resuscitation survival (ρ, 0.50; P < .001). Of note, there was no correlation between risk-adjusted acute resuscitation survival and postresuscitation survival (ρ, 0.09; P = .11). Compared with hospitals in the lowest RSSR quartile, hospitals in the highest RSSR quartile had higher rates of acute resuscitation survival (75.4% in quartile 4 vs 66.8% in quartile 1; P < .001) and postresuscitation survival (40.3% in quartile 4 vs 28.7% in quartile 1; P < .001), but the magnitude of difference was larger with postresuscitation survival. The findings suggest that hospitals that excel in overall in-hospital cardiac arrest survival, in general, excel in either acute resuscitation or postresuscitation care but not both; efforts to strengthen postresuscitation care may offer additional opportunities to improve in-hospital cardiac arrest survival.

Can we predict patient outcome before extracorporeal membrane oxygenation for refractory cardiac arrest?

BackgroundRefractory cardiac arrest resistant to conventional cardiopulmonary resuscitation (C-CPR) has a poor outcome. Although previous reports showed that extracorporeal cardiopulmonary resuscitation (E-CPR) can improve the clinical outcome, there are no clinically applicable predictors of patient outcome that can be used prior to the implementation of E-CPR. We aimed to evaluate the use of clinical factors in patients with refractory cardiac arrest undergoing E-CPR to predict patient outcome in our institution.MethodsThis is a single-center retrospective study. We report 112 patients presenting with refractory cardiac arrest resistant to C-CPR between January 2012 and November 2017. All patients received E-CPR for continued life support when a cardiogenic etiology was presumed. Clinical factors associated with patient outcome were analyzed. Significant pre-ECMO clinical factors were extracted to build a patient outcome risk prediction model.ResultsThe overall survival rate at discharge was 40.2, and 30.4% of patients were discharged with good neurologic function. The six-month survival rate after hospital discharge was 36.6, and 25.9% of patients had good neurologic function 6 months after discharge. We stratified the patients into low-risk (n = 38), medium-risk (n = 47), and high-risk groups (n = 27) according to the TLR score (low-flow Time, cardiac arrest Location, and initial cardiac arrest Rhythm) that we derived from pre-ECMO clinical parameters. Compared with the medium-risk and high-risk groups, the low-risk group had better survival at discharge (65.8% vs. 42.6% vs. 0%, p < 0.0001) and at 6 months (60.5% vs. 38.3% vs. 0%, p = 0.0001). The low-risk group also had a better neurologic outcome at discharge (50% vs. 31.9% vs. 0%, p = 0.0001) and 6 months after discharge (44.7% vs. 25.5% vs. 0%, p = 0.0003) than the medium-risk and high-risk groups.ConclusionsPatients with refractory cardiac arrest receiving E-CPR can be stratified by pre-ECMO clinical factors to predict the clinical outcome. Larger-scale studies are required to validate our observations.

Survival After In-Hospital Cardiac Arrest in Critically Ill Patients: Implications for COVID-19 Outbreak?

The coronavirus disease 2019 (COVID-19) outbreak is placing a considerable strain on U.S. healthcare systems by requiring both significant acute resources and endangering healthcare team members th...

Association of Fine Particulate Matter Exposure With Bystander-Witnessed Out-of-Hospital Cardiac Arrest of Cardiac Origin in Japan

Out-of-hospital cardiac arrests (OHCAs) are a major public health concern and a leading cause of death worldwide. Exposure to ambient air pollution is associated with increases in morbidity and mortality and has been recognized as a leading contributor to global disease burden. To examine the association between short-term exposure to particulate matter with a diameter of 2.5 μm or smaller (PM2.5) and the incidence of OHCAs of cardiac origin and with the development of initial cardiac arrest rhythm. This case-control study used data from cases registered between January 1, 2005, and December 31, 2016, in the All-Japan Utstein Registry, a prospective, nationwide, population-based database for OHCAs across all 47 Japanese prefectures. These OHCA cases included patients who had bystander-witnessed OHCAs and for whom emergency medical services responders initiated resuscitation before hospital transfer. A case-crossover design was employed for the study analyses. A prefecture-specific, conditional logistic regression model to estimate odds ratios was applied, and a random-effects meta-analysis was used to obtain prefecture-specific pooled estimates. All analyses were performed from May 7, 2019, to January 23, 2020. The main outcome was the association of short-term PM2.5 exposure with the incidence of bystander-witnessed OHCAs of cardiac origin. The differences in the distribution of initial cardiac arrest rhythm in OHCAs among those with exposure to PM2.5 were also examined. In total, 103 189 OHCAs witnessed by bystanders were included in the final analysis. Among the patients who experienced such OHCAs, the mean (SD) age was 75 (15.5) years, and 62 795 (60.9%) were men. Point estimates of the percentage increase for a 10-μg/m3 increase in PM2.5 at lag0-1 (difference in mean PM2.5 concentrations measured on the case day and 1 day before) demonstrated a statistically significantly higher incidence of OHCA across most of the 47 prefectures, without significant heterogeneity (I2 = 20.1%; P = .12). A stratified analysis found an association between PM2.5 exposure and OHCAs (% increase, 1.6; 95% CI, 0.1%-3.1%). An initial shockable rhythm, such as ventricular fibrillation or pulseless ventricular tachycardia (% increase, 0.6; 95% CI, -2.0% to 3.2%), was not associated with PM2.5 exposure. However, an initial nonshockable rhythm, such as pulseless electrical activity and asystole, was associated with PM2.5 exposure (% increase, 1.4; 95% CI, 0.1%-2.7%). Findings from this study suggest that increased PM2.5 concentration is associated with bystander-witnessed OHCA of cardiac origin that commonly presents with nonshockable rhythm. The results support measures to reduce PM2.5 exposure to prevent OHCAs of cardiac origin.