bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 221: Machine Learning Algorithms For The Prognostication Of Return Of Spontaneous Circulation
Authors: Liblik Kiera , Farrar Quintyn , Brooks Steven , Rajaram Akshay
Published: June 2023

Introduction:
Several factors are known to influence return of spontaneous circulation (ROSC) following out-of-hospital (OHCA) and in-hospital cardiac arrest (IHCA). Machine learning (ML) methods are capable of analyzing large datasets to elucidate the clinical and prognostic value of specific variables. In cardiac arrest, ML may help identify predictors of ROSC in OCHA and ICHA.

Purpose:
The present systematic review summarizes the literature on ML algorithms used to predict ROSC in OHCA and IHCA.

Methods:
PubMed, EMBASE, Web of Science, and Cochrane were searched to identify articles. Studies on human subjects with OHCA or IHCA which used ML methods to predict ROSC were included.

Results:
A total of 4,094 studies were identified through a literature search. Ten were included in the final analysis with a total sample size of 240,798 patients (240,798 (93%) male). Studies used logistic regression (n=7), random forest models (n=2), or deep learning (n=1). Sociodemographic variables beyond age (n=8) and sex (n=5) were not used. Variables used for predicting ROSC included age (n=8), type of rhythm (n=7), witnessed arrest (n=5), and time to emergency services arrival (n=5). Most models were built using data from OHCA patients (n=7), with only three focused on IHCA. Studies utilized a variety of parameters for reporting the prognostic value of their models, including predictive accuracy (69%-99%), area under the receiver operating characteristic curve (0.71-0.83), sensitivity (50.2%-76.0%), and specificity (61.0%-92.9%).

Conclusion:
Despite the prevalence of cardiac arrest and advances in AI, only ten studies examined ML in the prognostication of ROSC. Logistic regression was predominantly used in the included studies, and there is a paucity of data on the efficacy of deep learning models. Furthermore, heterogeneity in the predictive efficacy of studied ML models merits additional work and the need for large-scale trials comparing ML to conventional methods and clinician judgment. Critically, there is also a need for greater data inclusivity in model development, understanding that marginalized populations are less likely to receive CPR.
Abstract 225: Late Awakening In Comatose Survivors Of Out-of-hospital Cardiac Arrest
Authors: Tadel-Kocjancic Spela , Jazbec Anja , Noc Marko
Published: June 2023

Background:
Despite advanced neuroprognostication using neuron-specific enolase, electroencephalogram and brain imaging, prediction of neurological outcome in comatose survivors of out-of-hospital cardiac arrest (OHCA) remain challenging and early discontinuation of postresuscitation treatment may be harmful for patients with delayed awakening.

Hypothesis:
Significant proportion of comatose survivors of OHCA may regain consciousness only after discharge from intensive care unit (ICU).

Methods:
Consecutive comatose survivors of OHCA admitted to our ICU between January 1, 2003 and December 31, 2021 were investigated. Cerebral performance category (CPC) was used for evaluation of neurological recovery. CPC 1 indicated complete recovery, CPC 2 mild neurological impairment, CPC 3 severe neurological impairment and CPC 4 vegetative state.

Results:
A total of 1098 patients (63
+
14 years, 79% (864 of 1098) men) were enrolled. OHCA was witnessed in 88% (966 of 1098), basic life support was performed in 57% 630 of 1098), delay to emergency team arrival was 7.5
+
5.3 minutes and initial shockable rhythm was present in 77%. (851 of 1098). Reestablishment of spontaneous circulation (ROSC) was obtained after 12.9
+
11.8 minutes of advanced life support. Coronary angiography was performed in 74% (822 of 1098) and percutaneous coronary intervention in 52% (567 of 1098). Mechanical circulatory support was used in 16% (175 of 1098) and hypothermia (32-34 C) in 85% (940 of 1098). Among 740 patients who survived to ICU discharge on day 7 (median), 272 patients (36.8%) of patients remained in CPC 3-4 (
Figure).
Among these 272 patients, CPC 1-2 at hospital discharge was documented in 19.9%. (54 patients).

Conclusion:
Almost 20% of comatose survivors of OHCA without neurological recovery at ICU discharge may ultimately regain consciousness. This argues against premature withdrawal of care in step down units and normal wards.
Abstract 227: Acute Inpatient Rehabilitation And Social Determinants Of Health Are Associated With Functional Recovery Patterns At 12 Months Relative To Hospital Discharge From Cardiac Arrest.
Authors: Agarwal Sachin , Shen Edmund Q , Tincher Isabella M , Abukhadra Sabine L , Roh David , Park Soojin , Claassen Jan , Edmondson Donald E , Taylor Jacquelyn Y , Wagner Amy K , Callaway Clifton W
Published: June 2023

Introduction:
Cardiac arrest (CA) survivors have significant impairments and poor functional outcomes at hospital discharge. We assessed if discharge disposition to acute inpatient rehabilitation after CA-related hospitalization is associated with improved functional recovery at 12 months relative to alternative acute care hospital discharge dispositions.

Methods:
Adults with the return of spontaneous circulation after in-hospital or out-of-hospital CA between 2/1/2016- 1/31/2020 admitted to intensive care units in a single tertiary care center were enrolled in an observational, prospective cohort study. A series of logistic regressions were used to assess acute inpatient rehabilitation associations with good functional recovery patterns, defined as persistent Modified Rankin Score (mRS) 0-2, or absence of any worsening of mRS at 12 months relative to discharge mRS. The model included demographics, individual and structural-level Social Determinants of Health, and pertinent clinical characteristics.

Results:
Of 201 included patients (24% Hispanic and 19% Black; average age 56±16 years; 40% women), 63% (n=127) reported good functional recovery pattern. Patients who went to acute inpatient rehabilitation were significantly more likely to experience good recovery pattern (54.3% vs 37.8% with poor recovery pattern, p<0.01). In a multivariable model, acute inpatient rehabilitation was significantly associated with a good recovery pattern when compared to other discharge dispositions (home with out-patient rehabilitation services (odds ratio (OR), 0.3; CI, 0.1-0.8; p = 0.02), and skilled nursing facility (OR, 0.2; CI, 0.1-0.6; p<0.01). SDOH including minority race/ethnicity, poor insurance, premorbid unemployment, no carepartner or spouse, and patients with longer hospital length of stay had independent and significant associations with poor functional recovery patterns.

Conclusions:
Acute inpatient rehabilitation was associated with a good functional recovery pattern 12 months after hospital discharge from CA. Social determinants of health have an independent effect on the functional recovery patterns and should be systematically collected for future outcome-based studies.
Abstract 253: Decline In Initial Shockable Rhythm In Patients Treated With Public Access Defibrillators Over A 10-year Period
Authors: Torney Hannah , McAlister Olibhear , McQuaid Sarah , Harvey Adam , Kernaghan Amy , McEneaney David , Adgey Jennifer
Published: June 2023

Introduction:
Previous analysis of emergency medical services manual defibrillator recordings suggests that the proportion of patients with initial shockable rhythms during out-of-hospital cardiac arrest is decreasing over time. This analysis aims to determine if this decline also occurs in public access defibrillator data.

Methods:
Worldwide post-market data from HeartSine SAM PAD public access defibrillators was collected between 2012 and 2022. Presence of an initial shockable rhythm (ventricular fibrillation or ventricular tachycardia) was determined by the device algorithm decision and clinical overread. The proportion of patients who presented an initial shockable rhythm each year was calculated. Data was analysed using Minitab. Summary statistics were calculated for patient age and gender, and a logistic regression model was used to examine the proportion of initial shockable rhythm over time.

Results:
A total of 5404 patient events were collected. Seventy-four percent were male, and mean (SD) age was 61.2 (18.2) years. Proportion of initial shockable rhythm as a response to year was assessed, and occurrence of shockable rhythms decreased by approximately 6% per year [OR: 0.94, 95%CI (0.91, 0.96), p<0.001].

Conclusion:
In line with findings from emergency service resuscitation attempts, the proportion of initial shockable rhythms in patients treated with a public access defibrillator declined over a ten-year period.
Abstract 273: Epinephrine Dose Distribution And Impact On Survival After Extracorporeal Cardiopulmonary Resuscitation In Children
Authors: Ortmann Laura A , Raymond Tia T , Brunetti Marissa A , Himebauch Adam , Kempka Jessica , di Bari Shauna , Lyden Elizabeth , Lasa Javier J
Published: June 2023

Background:
Although AHA guidelines recommend a fixed epinephrine (epi) dosing frequency during cardiac arrest, it is unknown if a fixed dosing practice is both utilized and effective for EPCR events in children. We hypothesized that 1) epi dosing would not be uniformly distributed during ECPR events and 2) a strategy of limiting epi doses during ECPR would be associated with better survival to hospital discharge (SHD).

Methods:
This was a multicenter retrospective cohort study of ECPR after in-hospital cardiac arrest in children (< 18 years) between 2012 - 2019. Patient and arrest event details as well as epi dose and time-stamps were recorded. In patients with a CPR duration of ≥ 30 minutes, dosing strategies were categorized as either “frequent epi” (FE; average epi dosing interval of ≤ 5 mins/dose during the first 30 mins of CPR) or “limited epi” (LE; average dosing interval of ≤ 5 mins/dose for the first 10 mins followed by > 5 mins/dose through 30 mins). The primary outcome was SHD.

Results:
A total of 191 patients from 5 centers were included; overall SHD was 43% (82/191). Epi doses were not evenly distributed, with 66% (919/1385) of doses being given during the first half of CPR. Mean number of epi doses was similar between survivors and non-survivors in the first 10 mins (2.7 doses). After 10 mins, survivors received fewer doses than non-survivors per each 10 min interval (Figure). In the subset of patients that received ≥ 30 mins of CPR (n=147) the LE group had higher SHD [48% (14/52) vs. 27% (46/95), p=0.01] and improved odds of SHD after adjusting for age, sex, illness category, time of day, first pulseless rhythm and CPR duration [OR (95% CI) 4.2 (1.5-11.7); p =0.008].

Conclusion:
In contrast to AHA guidelines, epi dosing was not evenly distributed during events in this multicenter study of pediatric in-hospital ECPR. For children with CPR duration ≥ 30 minutes a strategy of limiting epi doses was associated with improved SHD.
Abstract 275: The First Series Of Hypothermic Out-of-hospital Cardiac Arrests In A Temperate Urban Area Resuscitated With Prehospital Or Inhospital Extracorporeal Cardiopulmonary Resuscitation: A Fifteen-year Observationnal Study
Authors: Soumagnac Tal , Raphalen Jean Herle , Yahiaoui Samraa , Vimpere Damien , An Kim , Mungur Akshay , Dagron Christelle , Carli Pierre , Hutin Alice , Lamhaut Lionel
Published: June 2023

Introduction:
Accidental hypothermia designates an unpredicted drop in body temperature below 35°C. The risk of ventricular fibrillation is major below 28°C and cardiac arrest is almost certain below 24°C. In such cases, conventional cardiopulmonary resuscitation is often inefficient.

Hypothesis:
Hypothermic out-of-hospital cardiac arrest (OHCA) occurs even in temperate urban areas and extracorporeal cardiopulmonary resuscitation (ECPR) has shown good outcomes with this indication.

Methods:
We conducted a retrospective observational study of patients admitted to a university hospital in Paris, France. We reviewed patients consecutively admitted between January 1, 2008 and April 31, 2022 and treated with prehospital or inhospital ECPR following refractory hypothermic OHCA. The primary outcome was survival at 28 days with good neurological outcomes, defined as Cerebral Performance Category (CPC) 1 or 2. We compared patients according to their cold air or cold water exposure.

Results:
A total of 38 patients were analysed. Patient characteristics and outcomes are detailed in Table 1. A total of 15 patients (40%) survived at 28 days, 13 (34%) of whom with good neurological outcomes despite a median low-flow of 85 min. No patient survived with good neurological outcomes in the cold-water group.

Conclusion:
Survival rates with favourable neurological outcomes at 28 days stood at 34% of all patients with hypothermic OHCA who were resuscitated with ECPR. Prehospital ECPR tended to show better survival results (39% vs 30%) but further data are needed to confirm this as the difference was not statistically significant. We found no survivors in the cold-water group raising the question of ECPR indication for these patients in temperate urban areas. In any case, temperature measurement should be systematic in OHCA and there should be predefined care pathways including ECPR for hypothermic OHCA patients even in urban settings with a temperate climate.
Abstract 277: Hyperoxemia Is Associated With Brain Death In Refractory Out-of-hospital Vt/vf Patients Treated With Extracorporeal Cardiopulmonary Resuscitation
Authors: Agdamag Arianne , Gutierrez Alejandra , Kalra Rajat , Elliott Andrea M , Marquez Alexandra , Alexy Tamas , Yannopoulos Demetris , Bartos Jason
Published: June 2023

Background:
Brain death is a major cause of death among refractory ventricular tachycardia/ventricular fibrillation (VT/VF) out-of-hospital cardiac arrest (OHCA) who are treated with extracorporeal cardiopulmonary resuscitation (ECPR). Studies regarding the clinical consequences of hyperoxemia in this population are lacking. We aimed to determine whether hyperoxemia (PaO
2
>300mmHg) is associated with brain death in patients treated with an established ECPR protocol.

Methodology:
This single-center retrospective study included consecutive patients presenting to the University of Minnesota between 2015-2021 with refractory VT/VF OHCA. All patients were treated with an ECPR protocol including VA-ECMO. All blood gases collected within the first 48 hours were reviewed and the highest and lowest values for PaO2, PaCO2, and lactate were recorded. The primary outcome was brain death. This was defined as a lack of brainstem reflexes on physical examination and herniation on CT imaging or lack of blood flow on a brain perfusion scan.

Results:
One-hundred and eighty-two patients met inclusion criteria and 141/182 (77.5%) had hyperoxemia. Presenting characteristics were comparable in both groups aside from higher initial PaCO
2
in patients who developed hyperoxemia (
Figure
). Brain death occurred in 42/141 (29.8%) of the hyperoxemia group vs 3/41 (7.3%) in the non-hyperoxemia group. After adjustment for age, CPR time, initial PaCO
2
and lactate, hyperoxemia was significantly associated with brain death (OR 5.2, 95% CI 1.4-19.0, p=0.014). The risk was independent of the number of hours spent with hyperoxemia (
Figure
). Overall survival was comparable between groups. Hypoxemia (PaO2 <60mmHg) occurred in 76/182 (41.8%) and was not associated with survival or brain death.

Conclusion:
Among refractory VT/VF OHCA patients treated with ECPR, hyperoxemia after the cardiac arrest is associated with brain death independent of the number of hours spent with hyperoxemia.
Abstract 278: Association Between Hospital Extracorporeal Life Support Volume And Outcome In Out-of-hospital Cardiac Arrest Patients
Authors: Choi Seul Ki , Song Kyoung J , Hong Ki Jeong , Sun Ro Young , Hong Won pyo , LEE Stephen Gyung Won , Lim Hyouk jae , Kim Ki Hong , Park Yong Joo , Yoon Hanna , Lee Gyeongmin , Lee Kang bin , Ko Eunsil , Kyung Sung Ho
Published: June 2023

Background:
The application of Extracorporeal Membrane Oxygenation(ECMO) and Extracorporeal Life support(ECLS) in hospitals is increasing. In the case of high-level skills, the volume of a specific treatment may be related to the outcome. There has been no discussion on the effect of the increasing utilization volume of ECLS in hospitals on the outcome of OHCA patients.

Objectives:
We want to determine how the hospital's ECMO volume affects the outcome of the overall OHCA patient visits to the hospital.

Methods:
We used Korean National OHCA Registry, and performed a cross-sectional study that collected adult EMS-treated cardiac origin OHCA patients between 2015 and 2019 in Seoul. We profiled the number of times ECLS, and hospitals that performed more than 20 times during the study period were regarded as high volume centers (HV centers), and the rest hospitals were defined as low volume centers (LV centers). The primary outcome was a neurologically good outcome (CPC 1 or CPC 2). The secondary outcome was survival at discharge. OHCA patients who visited the two groups were compared using a logistic regression model, and an interaction analysis was performed on the ECMO volume of the hospital and whether the patient had received ECLS.

Results:
Of the 17,248 included, 3,731 (21.63%) were transported to the HV center. The frequency of good neurological survival was not significant in the group transported to the HV center(aOR 1.08, 95% CI 0.9 - 1.29), but the frequency of survival to discharge was significantly higher(aOR 1.19, 95% CI 1.03 - 1.37). According to interaction analysis, OHCA patients who received ECLS at the HV center showed a significantly better neurological survival outcome(aOR 2.217, 95% CI 1.15 - 4.28), and the OHCA patients transported to the HV center, not receive ECLS had significantly better survival to discharge rates than those transported to the LV center (aOR 1.16, 95% CI 1.01 - 1.34).

Conclusions:
OHCA patients who were transported and received ECLS to hospitals with high ECMO volumes center had a significantly better neurological outcome. Those who were transported to the high-volume center had a better survival to discharge rate than patients transported to the low-volume one, even if they did not receive ECLS.
Abstract 279: Ecpr, A New Source Of Organs
Authors: Hutin Alice , BOURDIAULT Alexandre , Raphalen Jean Herle , VALENTIN Thomas , Soumagnac Tal , VIMPERE Damien , Ammar Hatem , DAGRON Christelle , An Kim , MUNGUR Akshay , Carli Pierre , Lamhaut Lionel
Published: June 2023

Purpose:
The scarcity of renal grafts is a major public health problem. New strategies are sought to overcome the problem of organ shortage. Organ donation after brain death is a major source of renal grafts. In our center, extracorporeal cardiopulmonary resuscitation (ECPR) is used as a 2nd line of treatment for refractory cardiac arrest. Despite this treatment, some patients present brain death and become eligible to organ donation. To this day, information is scarce on the long-term outcome of renal grafts from these patients. The objective of this study was to evaluate this outcome.

Methods:
We conducted a monocentric retrospective observational study between 2011 and 2017. The study was validated by the local ethics committee. We included patients who were eligible to organ donation after diagnosis of brain death and from whom at least one organ graft was procured and transplanted. Among these patients we compared those who were treated by ECPR for refractory cardiac arrest (ECPR group) and those who were not (control group).

Results:
During the study period, 45 patients were included, respectively 23 and 22 in the control and ECPR groups. Patients from the ECPR group were younger with less comorbidities (respectively 41+/-13 vs 63+/-19 years in the ECPR and control groups, p<0,044). However, they were more severe during their ICU stay, as shown by their SAPS II score which was significantly higher (80+/-13 vs 61+/-15 in the ECPR and control groups respectively, p<0,001). A total of 68 renal grafts were procured, transplanted, and studied (34 in each group). There was no difference between the 2 groups in terms of graft survival at 1 year (94.1 vs 82.4% in the ECPR and control group respectively, p=0,52).

Discussion-Conclusion:
Our study outlines that kidneys harvested from patients treated with ECPR have similar long-term outcome to organs retrieved from patients developing brain death without ECPR. Younger age and absence of comorbidities seem to compensate patient severity after cardiac arrest. One could hypothesize on a protective effect of ECPR on kidney function due to continuous blood flow delivered in the descending aorta. With the increase of ECPR cases, this strategy could be an increasing source of organs to address the issue of organ shortage.
Abstract 280: Extracorporeal Cardiopulmonary Resuscitation Outcomes In Children Without Underlying Cardiac Disease
Authors: Loaec Morgann , Himebauch Adam S , Reeder Ron , Alvey Jessica , Race Jonathan , Su Lillian , Lasa Javier J , Slovis Julia C , Raymond Tia , Coleman Ryan , Kilbaugh Todd J , Topjian Alexis A , Sutton Robert M , Morgan Ryan W
Published: June 2023

Introduction:
Extracorporeal cardiopulmonary resuscitation (ECPR) has been associated with improved outcomes compared to conventional CPR (CCPR) in children with underlying cardiac disease. There are limited data on ECPR survival outcomes in the non-cardiac population.

Hypothesis:
ECPR will be associated with improved survival to discharge in children without underlying cardiac disease with prolonged CPR.

Methods:
Retrospective cohort study using the AHA Get With The Guidelines® - Resuscitation registry of children (<18 years) without cardiac disease who received ≥30 minutes of CPR for in-hospital cardiac arrest between 2000-2020. Weighted propensity scores were used to balance ECPR and CCPR groups based on hospital and patient characteristics. Multivariable logistic regression incorporating these scores tested the association of ECPR with survival to discharge. A Bayesian logistic regression model was used to estimate the probability of a positive effect from ECPR. A secondary analysis explored temporal trends in ECPR relative to the index year of 2000.

Results:
Of 875 patients, 159 received ECPR and 716 received CCPR (median age 1 year, primary diagnosis respiratory insufficiency, median CPR duration 45 minutes for full cohort). Survival to discharge was similar between the ECPR group (21.4%) compared to the CCPR group (16.2%) in both the univariable analysis (p= 0.13) and the propensity-weighted multivariable logistic regression (aOR 1.44 [CI 0.85-2.44, p= 0.173]. The Bayesian model estimated an 85.1% probability of a positive effect of ECPR on survival to discharge. ECPR use increased over time (test for trend p<0.001).

Conclusion:
In children without cardiac disease who required ≥30 minutes of CPR, ECPR usage significantly increased in the last 20 years. Compared to CCPR, ECPR was not associated with a statistically significant increase in survival to discharge. However, a Bayesian model estimated weak evidence of a positive survival effect of ECPR.
Abstract 285: Traditional Cardiopulmonary Resuscitation In Cardiac Arrest For Patients On Venovenous Extracorporeal Membrane Oxygenation
Authors: Roberts Erin G , Odish Mazen F , Wardi Gabriel , yi Cassia , Pentony Erica , Sell Rebecca
Published: June 2023

Introduction:
Mortality for patients on VV-ECMO remains high despite increased use during the COVID-19 pandemic. Unlike VA-ECMO which provides life support for cardiac failure and can be used as a bridge to definitive therapy during cardiac arrest (e-CPR), patients who arrest while on VV-ECMO currently may undergo traditional cardiopulmonary resuscitation (CPR). This poses many challenges such as potential cannula position disruption of the VV-ECMO system during compressions and it is unclear if patients on VV-ECMO will benefit from being offered traditional CPR.

Hypothesis:
Traditional CPR is effective in patients who arrest while on VV-ECMO.

Methods:
A retrospective chart review of inpatient cardiac arrest data from a high-volume ECMO center was performed. Patients who arrested while on VV-ECMO were included. Data including demographics, etiology of arrest, return of spontaneous circulation (ROSC) and survival to discharge were reviewed. Survival data was compared with the ECLS International Summary of Statistics.

Results:
We identified 19 patients on VV-ECMO who underwent CPR for cardiac arrest between September 2012 and November 2021. The average age of the patients was 42.7 years and 89.5% (n=17) were men. Seven of the nineteen total patients (36.8%) were being treated for ARDS from COVID-19 pneumonia. The arrest occurred on average 35.6 days into hospitalization (range: 1-132 days). The initial rhythm was pulseless electrical activity in 13 patients (68.4%), and the etiologies of arrest included hypoxemia (n=10, 52.6%), ECMO machine failure or during oxygenator exchange (n=3, 15.8%), pneumothorax (n=2, 10.5%), and cardiac tamponade (n=1, 5.3%). ROSC occurred in all 19 patients (100%), however only 4 patients (21.1%) survived to discharge with good neurologic recovery. Survival to discharge for all-comers on VV-ECMO is 66%.

Conclusions:
While there is limited evidence for the effectiveness of traditional CPR for patients on VV-ECMO, in this sample, ROSC was universal and one-fifth of patients survived to discharge. Future studies should continue to study the utility of CPR on VV-ECMO and how to optimize technique to improve outcomes for these critically-ill patients.
Abstract 286: Hypothermic Out-of-hospital Cardiac Arrest: Favorable Outcomes, But With Limited Defibrillation Or Adrenaline Administration Effectiveness In The Prehospital Setting
Authors: Hongo Takashi , Naito Hiromichi , Yumoto Tetsuya , Yumoto Ryouhei , Suzuki Etsuji , Yorifuji Takashi , Nakao Atsunori
Published: June 2023

Introduction:
Hypothermic out-of-hospital cardiac arrest (OHCA) is assumed to be associated with favorable neurological outcomes compared with OHCA from other etiologies. However, supporting evidence is limited. In addition, inconsistencies for number of defibrillation and adrenaline administration attempts in prehospital management guidelines can be identified.

Hypothesis:
We evaluated whether hypothermic OHCA is associated with favorable outcomes compared with OHCA from other etiologies. Further, the effectiveness of defibrillation or adrenaline administration was evaluated.

Methods:
Using data from a nationwide, population-based retrospective study conducted in Japan from 2013 to 2016, we compared two OHCA patient groups: patients with hypothermic etiology and those with non-hypothermic etiology. The primary outcome measure was one-month favorable neurological outcomes, defined as Cerebral Performance Category score ≤ 2. Multivariable logistic regression was used to calculate odds ratios (ORs) and their confidence intervals (CIs) to evaluate the impact of hypothermic OHCA. We further looked for an association between prehospital management and neurological outcomes among patients with hypothermic etiology.

Results:
We divided the cohort of 477,606 OHCA patients into the hypothermic group (n=842) and the non-hypothermic group (n=476,763). The hypothermic group had significantly higher odds of favorable neurological outcomes (64/842 (7.6%) vs. 13,052/476,763 (1.4 %), adjusted OR 3.12, 95%, CI 1.96-4.96) compared with the non-hypothermic group. In the hypothermic group, prehospital defibrillation (OR 1.52, 95%, CI 0.86-2.68) and adrenaline administration (OR 1.32, 95%, CI 0.67-2.62) did not contribute to favorable neurological outcomes overall. However, when the data was stratified by age and number of shocks, three or less defibrillation attempts in patients under 65 years old (OR 3.37, 95%, CI 1.31-8.67) was associated with favorable neurological outcomes.

Conclusion:
We found that hypothermic OHCA was associated with a higher chance of a favorable neurological outcome. Even prehospital defibrillation seems to have limited efficacy for hypothermic OHCA.
Abstract 296: Relationship Between Emergency Medical Service Response Time And Bystander Cardiopulmonary Resuscitation In Children With Out-of-hospital Cardiac Arrest: A Nationwide, Population-based Observational Study
Authors: Funada Akira , Goto Yoshikazu
Published: June 2023

Introduction:
Bystander cardiopulmonary resuscitation (CPR) and a short response time for emergency medical services (EMSs) are important determinants of survival after out-of-hospital cardiac arrest (OHCA). As asphyxia cardiac arrest is more common than cardiac arrest from a primary cardiac event in children, effective ventilation is vital during pediatric OHCA.

Hypothesis:
There would be no difference in post-pediatric OHCA between standard bystander CPR (S-CPR) with rescue breaths and chest-compression-only bystander CPR (CC-CPR) before EMS arrival if EMS response time is extremely short.

Methods:
The study included 13,719 Japanese children (aged <18 years) from an All Japan Utstein-style registry who received bystander CPR post-OHCA between 2005 and 2019. Patients were divided into two groups: S-CPR (n = 5,369) and CC-CPR (n = 8,350). After propensity score matching, we compared the outcomes between the groups according to EMS response time. EMS response times were categorized into 13 groups: ≤2, 3-4, 5-6, 7-8, 9-10, 11-12, 13-14, 15-16, 17-18, 19-20, 21-22, 23-24, and ≥25 min. The primary study endpoint was 1-month neurologically intact survival, defined as a cerebral performance category score of 1 or 2 (CPC 1-2).

Results:
Propensity score matching was achieved for 4,639 of 5,369 patients with S-CPR (86,4%) and 4,639 of 8,350 patients with CC-CPR (55.6%). Overall 1-month CPC 1-2 rate in S-CPR was significantly higher than that of CC-CPR: 17.0% (788/4,639) vs. 9.3% (429/4,639,
P
<0.0001). There were no significant differences in 1-month CPC 1-2 rate between S-CPR and CC-CPR groups when EMS response times were ≤2 min (
P
= 0.17), 17-18 min (
P
= 0.55), 19-20 min (
P
= 0.14), 21-22 min (
P
= 0.23), 23-24 min (
P
= 1.00), and ≥25 min (
P
= 0.07). However, the rate of 1-month CPC 1-2 was significantly higher with S-CPR than with CC-CPR when the EMS response time ranged 3-4 min (
P
< 0.01) to 15-16 min (
P
< 0.01).

Conclusions:
CC-CPR for children with OHCA before EMS arrival had a similar association with S-CPR for 1-month neurologically intact survival when EMS response time was ≤2 min and ≥17 min onward. However, 1-month neurologically intact survival in S-CPR was superior to CC-CPR when EMS response time was outside this range.
Abstract 297: Chronic Oral Anticoagulant Use By Emergency Medical Services Patients In The United States
Authors: Wang Henry , Yu Mengda , Chu Ching Min , Sharkey-Toppen Travis , Hyer Madison , Nassal Michelle , Delamare Alix , Powell Jonathan , Wei Lai , Panchal Ashish R
Published: June 2023

Objective:
Oral anticoagulant (OAC) use raises risk of death in life-threatening conditions such as hemorrhagic stroke and trauma, including traumatic brain injury. Only limited data describe the characteristics of individuals who use OACs. We sought to describe the national characteristics of Emergency Medical Services (EMS) patients with a history of OAC use.

Methods:
We used the 2018-2020 ESO data set, a national EMS electronic health record system. We included adults (age≥18 years) receiving 911 prehospital emergency care. OAC use included warfarin, dabigatran, rivaroxaban and apixaban. We determined the incidence of EMS calls by OAC users as well as their variation by EMS agency. We compared EMS call, patient, and response characteristics between OAC and non-OAC users, including primary impressions and hospital diagnoses.

Results:
Among 2,100 EMS agencies, there were 16,244,550 adult 911 prehospital events, including 948,671 by OAC users (58 per 1,000 events). OAC call incidence varied by EMS agency; median 53 per 1,000 events (IQR 27 to 83). Compared with non-OAC users, OAC users were more likely to be >70 years (64.6% vs. 30.3%, OR 4.19, 95% CI: 4.17 to 4.21), white race (77.4% vs. 65.8%, OR 2.62, 95 CI: 2.47 to 2.78) and non-Hispanic (84.4% vs. 78.0%, OR 2.66, 95% CI 2.63 to 2.69). Calls involving OAC users were more likely at nursing homes (17.9% vs. 9.1%, OR 2.16, 95% CI: 2.14 to 2.17) but less likely to involve trauma (17.8. vs. 21.6%, OR 0.787, 95% CI: 0.783 to 0.791) or cardiac arrest (1.2 vs. 1.4%; OR 0.89, 95% CI: 0.87 to 0.90). Among OAC users, the most common EMS primary clinical impressions were chest pain (7.4%), altered mental status (7.3%), injury (6.5%), abdominal pain (4.3%), and brain injury (2.8%). Among the 67,567 OAC prehospital encounters linked to hospital data, the most common primary discharge diagnoses were: ICD10 R00-R99 signs and symptoms (23.1%), I00-I99 circulatory diseases (19.9%), and J00-J99 respiratory diseases (10.1%).

Conclusions:
1 in 17 adult prehospital encounters involve OAC users. While OAC use was common in high-risk populations, presentation with injury was less common. These results characterize the presentation of this high-risk population in EMS care.
Abstract 300: Evaluation Of An Electrocardiogram Based Analytic For Predicting Future Episodes Of Hemodynamic Instability
Authors: Benson Bryce , Belle Ashwin , Lee Sooin , Medlin Richard P
Published: June 2023

Background:
Clinicians rely on vital signs (tachycardia with hypotension) to identify hemodynamically unstable patients. The Analytic for Hemodynamic Instability (AHI) System provides an indication of hemodynamic deterioration before it is evident via vital signs. It uses only routinely collected ECG monitor data to generate a simple binary output (indicating signs of hemodynamic instability-Red or stability-Green) and is automatically updated every two minutes.

Hypothesis:
Continuous real-time hemodynamic status obtained from analysis of ECG signals can predict an episode of hemodynamic instability before it's evident via vital signs, with clinically actionable lead time.

Methods:
In this retrospective observational study, an episode of hemodynamic instability (EHI) was defined as 10 continuous minutes or more where hypotension (systolic BP<90 mmHg or mean BP<70 mmHg) combined with tachycardia (heart rate ≥ 100 bpm) was present. The AHI System processed continuous ECG data from 362 consecutive adult ICU patient encounters (146, 40.3% female) undergoing continuous BP and HR monitoring via arterial line and ECG, who experienced at least one EHI. In this analysis, only the first occurrence of an EHI per patient encounter was used to see if the AHI System predicted the episode before vital signs showed any indication.

Results:
Of the 362 patients, AHI correctly predicted the first EHI in 85% of the patients (308/362). Of those, AHI’s median lead time (predominantly repeating AHI-Red indications) was 57 minutes prior to first EHI, with 25th and 75th percentiles at 14 minutes and 3.2 hours, respectively. AHI’s average lead time was 4 hours.

Conclusion:
Results suggest that this ECG-based analytic can potentially notify healthcare providers of future patient deterioration with clinically actionable lead times. The benefit of this analytic could extend further for ECG monitored patients in lower levels of care where hemodynamic status is typically evaluated manually and intermittently. This potentially enables appropriate preemptive clinical action, thereby reducing failure to rescue and increasing vigilance for unseen at-risk patients.

Footnote:
AHI is an FDA-cleared device for sale in the US.
Abstract 303: Evaluating The Utility Of A Predictive Analytic For Reducing Intensive Care Unit Readmissions
Authors: Benson Bryce , Lee Sooin , Belle Ashwin
Published: June 2023

Background:
The reported incidence of readmission (bounceback) to the ICU ranges from 4% to 10% of the total number of ICU admissions. Studies have shown that patients readmitted to the ICU have significantly higher mortality rates, longer lengths of stay, and higher costs than patients who survive the ICU and are not readmitted. Being able to tell whether patients have high or low risks of returning to the ICU could help physicians optimize the timing of ICU discharge.

Hypothesis:
A single lead continuous ECG based real-time analytic can help reduce ICU readmission rates.

Methods:
This retrospective analysis considered any admission back to the ICU following transfer to a lower-level care during the same hospitalization as an ICU Readmission. This study included 65 consecutive Michigan Medicine ICU patients who were transferred to a lower level of care and had ECG waveforms collected in real time. The Analytic for Hemodynamic Instability – Predictive Indicator (AHI-PI) processed the ECG to predict the likelihood of a future episode of hemodynamic instability with High, Moderate, and Low Risk indicators, which are updated every 2 minutes.

Results:
Of the 65 consecutive patients transferred from ICU to a lower-level of care, 14 patients (22%, 14/65) had AHI-PI High Risk indication prior to transfer. The remaining 51 patients (78%, 51/65) had AHI-PI Moderate or Low Risk indication prior to transfer. Of the AHI-PI High Risk indicated subgroup, 29% of patients had ICU Readmissions. In the other subgroup, only 10% did. This means that physicians with access to AHI-PI Risk indicators could potentially reduce ICU Readmission rates by 66% (from 29% to 10%). Further, the subgroup with no AHI-PI High Risk indication had an average of 73 hours (median 41 hours) of AHI-PI Moderate or Low Risk indication prior to transfer.

Conclusion:
Results indicate that patients with AHI-PI High Risk indication prior to transfer had higher risks of ICU Readmission, compared to those without. Prolonged AHI-PI Moderate or Low Risk indication prior to transfer can potentially help physicians decide to transfer patients earlier than otherwise. This can ultimately help reduce lengths of stay and improve bed and resource utilization in the ICU.

Footnote:
AHI is an FDA-cleared device for sale in the US.
Abstract 308: Efficacy Of Distance Learning For Cardiopulmonary Resuscitation Training Utilizing Smartphone App And Mannikin Delivery-collection System
Authors: LEE Stephen Gyung Won , Hong Ki Jeong , Song Kyoung J , Hong Wonpyo , Park YongJoo , Kim Ki Hong , Yoon Hanna , Lim Hyouk Jae , Choi Seul Ki , Lee Gyeongmin , Lee Kang bin
Published: June 2023

Aim of the study:
Effective CPR training is important for provision of high-quality bystander cardiopulmonary resuscitation (CPR). However, the COVID-19 pandemic has hindered conventional face-to-face CPR training. To overcome the limitation, we developed a distance learning CPR training course (HEROS-Remote) that utilized a smartphone app and a delivery-collection system for CPR training manikins. The objective of the study was to evaluate the efficacy of the HEROS-Remote course by comparing chest compression quality between trainees who participated in the conventional CPR training (C-training) and HEROS-Remote course (R-training).

Methods:
The non-inferiority trial included adult nonhealthcare providers who applied for CPR training. Both groups underwent 2-minute post-training chest compression test followed by course survey on trainees’ course and delivery system satisfaction. The primary outcome of the study was mean chest compression depth during the 2-minute post-training test.

Results:
A total of 180 trainees were enrolled with 90 trainees for each training group. There was no statistically significant difference in chest compression depth between R-training and C-training groups (67.4 vs. 67.8, p=0.78) as well as proportion of adequate chest compression depth, chest compression rate, proportion of chest compressions with complete chest recoil and chest compression score (90.8 vs. 92.1, p=0.69; 110.8 vs. 110.4, p=0.60; 89.8 vs. 94.7, p=0.05; 92.7 vs. 95.5, p=0.16, respectively). In the R-training group, 90.0% of the trainees were satisfied with the course, 96% responded that the delivery system was satisfactory and convenient.

Conclusion:
The R-training course was noninferior to the C-training course. The distance learning CPR training method utilizing smartphone app and mannikin delivery-collection system had high user satisfaction and was logistically feasible.
Abstract 322: Impact Of Safety Net Hospital Burden On Outcomes Of In-hospital Cardiac Arrest In The United States.
Authors: Olanipekun Titilope , Abe Temidayo , Chris-Olaiya Abimbola , Effoe Valery S , Bhardwaj Abhishek , Harrison Michael F , Moreno Franco Pablo , Guru Pramod , Sanghavi Devang
Published: June 2023

Background:
Safety net hospitals treat a large burden of uninsured, or Medicaid insured patients, and have been linked to worse outcomes across several medical and surgical conditions. Currently, there is limited data on the effect of safety net burden on outcomes of inpatient cardiopulmonary resuscitation (CPR) for patients that suffered in-hospital cardiac arrest (IHCA) in the US.

Hypothesis:
Patients that experience IHCA in high burden safety net hospitals (HBH) will have worse outcomes compared to low burden safety net hospitals (LBH).

Methods:
Using the National Inpatient Sample database, from 2008 – 2018, we identified patients aged ≥ 18 years who experienced IHCA, using International Classification of Diseases (ICD) codes. Hospitals’ safety net burden was calculated from the proportions of Medicaid and uninsured patients using previously published methodology and categorized into LBH and HBH. Multivariate regression models were used to estimate the odds of key clinical outcomes

Result:
From 2008 to 2018, an estimated 555,016 unweighted adult hospitalizations underwent CPR for IHCA, out of which 19.2 % occurred at LBH and 55.2 % occurred at HBH. Compared with LBH, patients at HBH on average were younger 62 years ± 20 vs 67 years ± 17), less likely to be of White race, and more likely to be in the lowest median household income. On multivariate regression analysis, HBH was associated with lower chances of survival to hospital discharge (aOR 0.88; 95% CI 0.85 – 0.96) and lower odds of routine discharge (aOR 0.6; 95% CI 0.47 – 0.75)), compared to LBH. Patients who suffered IHCA in safety net hospitals with medium and large hospital bed size (aOR 0.96; 95% CI 0.94 – 0.98) and those publicly owned (aOR 0.95; 95% CI 0.92 – 0.98) were less likely to survive to hospital discharge. Median household income of patients in the 26
th
– 100
th
quartile and hospital location in the Midwest and Southern region were associated with better odds of hospital survival.

Conclusion:
Our study suggests that patients who experience IHCA at HBH had lower rates and odds of in-hospital survival and also less likely to be routinely discharged home. Patients’ income level and hospital-level characteristics appear to contribute to survival.
Abstract 332: Does Concomitant Left Ventricular Unloading Improve Outcomes Of Cardiogenic Shock Managed By Venoarterial Extracorporeal Membrane Oxygenation? Analysis Of National Inpatient Sample Database 2019
Authors: Udongwo Ndausung , Narra LakshmiRekha , Mararenko Anton , Alshami Abbas , Fatuyi Michael , Abe Temidayo , Olanipekun Titilope , Upadhyaya Vandan D , Dhulipala Vishal , Dominic Jerry , kurtz jack , Kossack Andrew , Saybolt Matthew , Selan Jeffrey , Sealove Brett , Singh Deepak , Almendral Jesus
Published: June 2023

Introduction:
Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is often used in patients with cardiogenic shock. However, this strategy can lead to left ventricular (LV) distention, thus compromising myocardial recovery. Therefore, concomitant LV unloading with an Impella device (Abiomed, Danvers, MA) has gained a wide interest to promote LV recovery. We aimed to investigate the in-hospital outcomes of patients with myocardial infarction and cardiogenic shock undergoing VA-ECMO with Impella (ECPELLA) versus VA-ECMO alone.

Methods:
We conducted a retrospective cohort study using the 2019 National Inpatient Sample Database. Variables were identified using their International Classification of Diseases, 10th revision (ICD-10) codes. Descriptive bivariate and multivariate analyses were performed. A p-value <0.05 was considered statistically significant.

Results:
A total of 1915 records of acute myocardial infarction and cardiogenic shock treated with VA-ECMO were identified. Of these, 625 underwent ECPELLA, and 1,290 underwent VA-ECMO alone. Baseline characteristics and complication rates are listed in Table 1. Inpatient mortality rate was not statistically different between the ECPELLA and the VA-ECMO groups [50.4% (n=315) vs 46.1% (n=595), respectively, p=0.08]. In addition, a multivariable logistic regression model adjusting for potential confounders (baseline characteristics in Table 1, as well as primary expected payer, left heart catheterization, and initial presentation with cardiac arrest) did not show a mortality benefit for ECPELLA over VA-ECMO (OR 1.206, 95% CI 0.967-1.50, p=0.097). However, rates of acute renal failure requiring hemodialysis and intracranial hemorrhage were lower in the ECPELLA group.

Conclusion:
Our data suggests that there is no survival to hospital discharge benefit for ECPELLA vs VA-ECMO. Prospective studies are warranted to validate our findings.

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Abstract 9262: The Clinical and Electrophysiologic Manifestations of Cardiac Tumors: A Single-Center Retrospective Study
Authors: Madnick David , Vallabhaneni Srilakshmi , OQuinn Rupal , Guandalini Gustavo , Dixit Sanjay , Frankel David S , RILEY Michael P , Nazarian Saman , Deo Rajat , Callans David J , Epstein Andrew E , Marchlinski Francis E , Fradley Michael , Hyman Matthew C
Published: June 2023

Introduction:
Cardiac tumors are rare and their effect on the cardiac conduction system is not well-described. Currently there is no recommendation for routine arrhythmia screening in this population. This study aimed to characterize the clinical presentation and electrophysiologic manifestations of patients with cardiac tumors.

Methods:
A radiologic database from a four-hospital health system was queried to identify patients with a cardiac tumor diagnosed on CMR from 2003-2021. The electronic health record, ECGs, arrhythmia monitors, echocardiograms and CMRs were reviewed for each patient.

Results:
Forty-nine patients were identified with intra-cardiac or pericardial tumors. The cohort had a mean age of 57.3 ±14.6 years old and was 53% female. Cardiovascular risk factors were prevalent: HTN (59%), HLD (43%), DM (26%), CAD (20%). Common presenting symptoms were SOB (30.6%), palpitations (24.5%) and chest pain (20.4%); many patients had no overt cardiac symptom (42.9%). By CMR, tumors were classified as pericardial (44.9%) vs myocardial (55.1%), primary tumor (57.1%) vs secondary tumor (42.9%) and located nearest the atrium (24.5%), ventricle (55.1%) or both (14.3%). Twenty-three patients (47%) had tumors that were labeled as malignant, with the most common diagnoses being diffuse large B-cell lymphoma (DLBCL, 10.2%), non-small cell lung cancer (8.2%) and melanoma (6.1%). Non-trivial pericardial effusions were common (24.5%), with one case complicated by tamponade. Seven patients (14.2%) were documented to have cardiac arrhythmias including one patient with sudden arrhythmic death (SAD). Neither pericardial effusion (OR 3.7, CI 0.5-29.6) nor atrial tumor location (OR 2.8, CI 0.4-21.8) was predictive of atrial fibrillation or SVT. Ventricular arrhythmias were observed in patients with ventricular tumors (11.8%), but not atrial tumors (0%). Sustained VT was found in two patients with invasive DLBCL.

Conclusion:
Cardiac tumors are associated with frequent cardiac symptoms, pericardial effusions and cardiac arrhythmia. Sustained VT was documented in two patients with DLBCL in the ventricle, one of whom experienced SAD. Prospective studies employing long-term rhythm monitoring may be warranted to inform the need for arrhythmia screening.