bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 115: One-Year Outcomes in Individual Domains of the Cerebral Performance Category Extended
Authors: Flickinger Katharyn L , Repine Melissa J , Jaramillo Stephany , Koller Allison C , Holm Margo , Skidmore Elizabeth , Callaway Clifton W , Rittenberger Jon C
Published: July 2021

Introduction:
Cognitive and physical impairments are common in cardiac arrest survivors. Global measures including the Modified Rankin Scale (mRS), Cerebral Performance Category (CPC) and the 10-domain CPC-Extended (CPC-E) tend to improve over 1 year. The CPC-E is scored from 1-5 with higher scores signifying greater impairment. However, with the CPC-E, individual functional domains (alertness, logical thinking, attention, motor skills, short-term memory, basic and complex activities of daily living (ADL), mood, fatigue, and return to work) may recover at different rates.

Hypothesis:
We hypothesized that patients would have recovery in all domains of the CPC-E at 1 year after index cardiac arrest.

Methods:
A prospective cohort study of cardiac arrest survivors was conducted between 2/1/16 and 5/31/17. Chart review was done for baseline demographic data. Outcome measures including mRS, CPC, and CPC-E scores were assessed at discharge, 3 months, 6 months, and 1 year. We defined recovery of a CPC-E domain when >90% of patients had scores of 1-2 in that domain.

Results:
Of 71 subjects, 35 completed the CPC-E at discharge, 35 at 3 months, 25 at 6 months and 31 at 1 year. The most common reasons for exclusion were patient declined or were lost to follow up. The majority (N=37; 52%) were female, with a mean (SD) age of 58(17) years. Most arrests occurred out of hospital (N= 49; 69%), 27 (38%) had a shockable rhythm and the majority (N=37; 54%) were discharged home. CPC-E domains of alertness (N=35, 100%) logical thinking (N=35; 100%), and attention (N=33; 94%) recovered by hospital discharge. BADLs were recovered by 3 months (N=33; 94%). The majority of patients (N=24;77%) experienced slight-to-no disability or symptoms (mRS 0-2 / CPC 1-2) at 1 year follow up. CPC-E short term memory (67%), motor (87%), mood (87%), fatigue (13%), complex ADL (74%), and return to work (55%) did not recover fully by 1 year.

Conclusions:
In survivors of cardiac arrest, CPC-E domains of alertness, logical thinking, and attention recover rapidly, while domains of short term memory, motor, mood, fatigue, complex ADL and ability to return to work are chronically impaired 1 year after arrest. Interventions to improve recovery in these domains are needed.
Abstract 120: Epidemiology and Outcomes of Cardiopulmonary Resuscitation Events in the Neonatal Intensive Care Unit
Authors: Ahmad Kaashif A , Velasquez Steven G , Henderson Cody L , Kohlleppel Katy L , LeVan Jaclyn M , Stine Christina M , Bhalala Utpal S
Published: July 2021

Introduction:
Limited data exists regarding cardiopulmonary resuscitation (CPR) in infants in the Neonatal Intensive Care Unit (NICU). Objectives included determining the incidence, demographics, diagnoses, and outcomes of infants who require CPR across 10 NICUs in San Antonio, Texas.

Methods:
We conducted a retrospective review of in-NICU CPR events requiring chest compressions for 1 minute from 2012 - 2017. Included NICUs provided the following levels of care: two level IV, two high acuity level III, four low acuity level III, and two level II. Case identification occurred by reviewing death summaries and CPR coding in the electronic medical record.

Results:
In total, 139 infants (81 or 58% male) required 211 episodes of CPR. CPR incidence per 1000 patient days was 0.68, 0.37, 0.02 and 0 among level IV, high acuity level III, low acuity level III, and level II NICUs, respectively. Median birth weight was 945 (IQR 630, 2243) grams, gestational age at birth 27 (IQR 24, 34) weeks and age at CPR 11 (IQR 1, 42) days. Only 27 events (13%) occurred in term infants.

Ninety-three CPR events (44%) had a primary respiratory etiology, 38 (18%) circulatory, 36 (17%) infectious, and 24 (11%) metabolic. Term and preterm infants had significantly different CPR etiologies (p=0.036). Circulatory etiologies were more common in term infants (37% vs 15%) with respiratory etiologies being less common (33.3% vs 46.2%). The most common rhythm documented leading to initiation of CPR was bradycardia (63%), followed by asystole (19%), and pulseless electrical activity (14%). The median duration of CPR was 10 (IQR 4, 25.5) minutes and chest compressions 8 (IQR 3, 18) minutes. While 135 of 211 CPR events (64%) had ROSC, only 22 of 139 patients (16%) survived to hospital discharge. The rate of ROSC among Level IV NICUs was significantly higher than in high acuity level III NICUs (68.2% vs 51.9%, p = 0.034).

Conclusions:
NICU CPR events occur most commonly in premature infants and are respiratory in origin. Bradycardia is the most common initial rhythm requiring CPR in the NICU. The incidence of CPR and the rate of ROSC are higher in level IV than level III NICUs. Further investigation is needed into factors associated with ROSC for in-NICU CPR.
Abstract 121: The Influence of Age, Race, and Ethnicity on Public Automated External Defibrillator Use and Outcomes of Pediatric Out-of-Hospital Cardiac Arrest in the United States: An Analysis of the Cardiac Arrest Registry to Enhance Survival (CARES)
Authors: Griffis Heather , Wu Lucy , Naim Maryam , Tobin Joshua , McNally Bryan , Vellano Kimberly , Quan Linda , Markenson David , Bradley Richard , Rossano Joseph
Published: July 2021

Introduction:
Automated external defibrillators (AEDs) are an important link in the chain of survival following out-of-hospital cardiac arrest (OHCA). While the use of AEDs are clearly beneficial for OHCA in adults, there are few data on the overall use and outcomes of public AED use in children.

Hypothesis:
AED use is uncommon in children and associated with neurologically favorable survival.

Methods:
We conducted an analysis of the Cardiac Arrest Registry to Enhance Survival database. Inclusion criteria were age ≤ 18 years of age, public arrests, and non-traumatic OHCA from January 1, 2013 through December 31, 2017. Neurologically favorable survival was defined as a Cerebral Performance Category Scale of 1 or 2 at hospital discharge.

Results:
Of 971 public pediatric OHCA (66% male, 32% white), AEDs were used by bystanders in 117 (10.3%). AEDs were used among 2.3% of children aged ≤ 1 year (infants), 8.3% of 2-5 year-olds, 12.4% of 6-11 year-olds, and 18.2% of 12-18 year-olds (p<0.001). AED use was similar among white (11.1%), black (9.1%), and Hispanic children (8.1%) (p=0.84). AED use was more common with the provision of bystander CPR (19.1%) vs no bystander CPR (0.9%), witnessed arrests (16.0%) vs unwitnessed arrests (4.7%), and arrests with a shockable rhythm (23.6%) vs a nonshockable rhythm (6.3%) (p<0.001 for all). Overall, adjusted neurologically favorable survival was 29.1% (95% CI 22.7%, 35.5%) when a bystander used an AED compared to 23.7% (95% confidence interval [CI] 21.1%, 26.3%) for no bystander AED use (p=0.11). There was a significant interaction with age and race/ethnicity. AEDs were associated with neurologically favorable survival among children aged 12-18 years (p=0.04) but not associated with neurologically favorable survival in children ≤ 1 year (p=0.43), 1-5 years (p=0.16) or 6-11 years (0.41). AEDs were also associated with neurologically favorable survival in white children (p=0.01) but not with black (p=0.97) or Hispanic children (p=0.06).

Conclusions:
AED use is uncommon in children suffering OHCA but is associated with improved neurologically favorable survival. The benefit of AEDs was evident mostly for adolescents and white children. Further study is needed to understand these disparities in AED use and outcomes after AED use.
Abstract 124: Levels of Catecholamines in the Plasma of Patients With Cardiopulmonary Arrest
Authors: Oshima Kiyohiro , Hagiwara Shuichi , Murata Masato , Aoki Makoto , Nakajima Jun , Sawada Yusuke , Isshiki Yuta , Ichikawa Yumi
Published: July 2021

Purpose:
The efficacy of epinephrine (Ep) administration to patients with cardiopulmonary arrest (CPA) remains controversial, and correlation between plasma levels of catecholamines and prognosis in CPA patients is unclear. The purpose of this study is to evaluate the importance of the plasma levels of catecholamines at the time of admission to the hospital prior to the administration of Ep in CPA patients.

Methods:
This was a prospective, observational clinical study, approved by the ethics committee of Gunma University Hospital. Patients with CPA transferred to our hospital were enrolled prospectively between July 2014 and July 2017. The levels of catecholamines (Ep, norepinephrine [NEp], and dopamine [DOA]) and vasopressin (antidiuretic hormone [ADH]) in the plasma were measured using blood samples obtained at the time of admission to our hospital (prior to the administration of Ep). Patients were divided into two groups: the return of spontaneous circulation (ROSC)(+) group and the ROSC(-) group. The levels of these agents in the plasma and the conditions of resuscitation were compared between these two groups.

Results:
Blood samples were obtained from 170 patients. In 48 patients, the cause of CPA was cardiogenic and Ep was not administered prior to admission to the hospital. The ROSC(+) and ROSC(-) groups included 14 and 34 patients, respectively. The frequency of prehospital defibrillation was significantly higher in the ROSC(+) group, whereas prehospital resuscitation time was significantly shorter in the ROSC(+) group. Moreover, the levels of Ep and NEp in the plasma were significantly lower in the ROSC(+) group.

Conclusions:
Increased levels of Ep in the plasma may not be associated with the acquisition of ROSC in patients with cardiogenic CPA.
Abstract 13: Cardiac Arrest-Induced Posttraumatic Stress Increases 1-Year Risk of Major Adverse Cardiovascular Events and All-Cause Mortality
Authors: Agarwal Sachin , Presciutti Alex , Cornelius Talea , Birk Jeffrey L , Roh David J , Park Soojin , Claassen Jan , Elkind Mitchell S , Edmondson Donald E
Published: July 2021

Importance:
Many cardiac arrest (CA) survivors develop posttraumatic stress disorder (PTSD) symptoms (i.e., CA-induced PTSD). The association of CA-induced PTSD with secondary mortality and cardiovascular risk is unknown.

Methods:
A prospective, observational, cohort study of adults with return of spontaneous circulation after in-hospital or out-of-hospital CA at a tertiary-care center between September 2015 and September 2017. A consecutive sample of survivors with sufficient mental status to self-report CA-induced PTSD symptoms at hospital discharge were included. The combined primary end point was all-cause mortality (ACM) or a major adverse cardiovascular event (MACE)—hospitalization for nonfatal MI, unstable angina, congestive heart failure (CHF), urgent/emergency coronary revascularization procedures, or urgent implantable defibrillators/pacemaker (ICDs/PPM) placements within 12 months of discharge. In-person assessments for CA-induced PTSD were performed within 24 hours of hospital discharge. PTSD symptomatology was assessed via the PTSD Checklist - Specific (PCL-S) scale; a suggested diagnostic cut-off of 36 for specialized medical settings was adopted. Outcomes for patients meeting (vs. not meeting) this cutoff were compared using Cox regression with adjustment for demographic and clinical covariates.

Results:
Of 114 included patients, 36 (31.6%) screened positive for CA-induced PTSD at discharge (median 21 days post-CA; interquartile range 11-36). During the follow-up period (median = 12.4 months, range 10.2-13.5), 10 (8.8%) died and 29 (25.4%) experienced a recurrent MACE: rehospitalizations due to MI (n=4, 13.8%), UA (n=8, 27.6%), CHF exacerbations (n=4, 13.8%), emergency revascularizations (n=5, 17.2%), and ICDs/PPM placements (n=8, 27.6%). CA-induced PTSD was associated with ACM/MACE in univariate (Hazard Ratio [HR] =3.19; 95% confidence interval [CI], 1.7-6.0) and in models adjusted for age, sex, charlson comorbidity index and nonshockable initial rhythms (HR=3.2; CI, 1.7-6.1).

Conclusions:
PTSD is common after CA, and survivors with CA-induced PTSD had significantly higher risk of death and cardiovascular events. Further inquiry into underlying mechanisms is warranted.
Abstract 130: Pediatric Cardiac Arrest: Adult Defibrillation Energies are Safe and Effective When Treating a Pediatric Porcine Model
Authors: Davis Laura , McAlister Olibhéar , McCartney Ben , Torney Hannah , Crawford Paul , Gregson Rachael , Funston Rebecca , Harvey Adam , McEneaney David , Clutton Eddie , Adgey Jennifer
Published: July 2021

Objective:
When attempting defibrillation in an out-of-hospital pediatric patient, the use of a reduced energy is recommended by the resuscitation guidelines due to concerns surrounding potential myocardial damage. This study investigated the effectiveness (first shock success) and safety (myocardial damage) of using adult defibrillation energies in a pediatric model of cardiac arrest.

Methods:
Twelve piglets (9.5-25.5 kg; typical weight range of 1 to 8 year old children) were anaesthetized and VF was electrically induced. After 15 seconds of untreated VF, defibrillation was delivered using either Protocol A (adult energies; 150J) or Protocol B (pediatric energies; 75J). Following successful defibrillation, a 3 minute rest period was allowed for the heart to recover before VF was again induced. Blood samples were collected and analyzed for cardiac troponin I (cTnI). After 20 shocks were delivered, each animal remained anaesthetized and monitored for 6 hours.

Results:
A total of 240 shocks were delivered across both protocols with adult and pediatric energies providing comparable first shock success rates of 98.3% (116/118) and 96.6% (112/116). Prior to the induction of VF, Protocols A and B presented with equivalent median (IQR) levels of cardiac damage marker cTnI; 0.04 (0.02, 0.07) ng/ml (
n
=6) and 0.05 (0.03, 0.08) ng/ml (
n
=6), respectively. Comparable cTnI results were also observed upon completion of the defibrillation phase: Protocol A – 0.23 (0.12, 0.32) ng/ml; Protocol B – 0.20 (0.12, 0.27) ng/ml. There was 100% (12/12) survival after the 6 hour monitoring period with both protocols presenting similar cTnI: Protocol A – 0.32 (0.27, 0.55) ng/ml; Protocol B – 0.28 (0.20, 0.46) ng/ml. There were no clinically significant differences observed between the adult and pediatric defibrillation energy groups. Furthermore, histopathological evaluation revealed no discernible difference in cardiac damage between energy protocols.

Conclusion:
This study demonstrates that adult defibrillation energies are as effective in terminating VF and do not produce statistically higher levels of cTnI than pediatric defibrillation energies. These results suggest that adult defibrillation energies are appropriate for the treatment of pediatric cardiac arrest.
Abstract 133: "I’m Not the Same Person....": Understanding Cardiac Arrest Survivorship and Long -Term Outcomes From the perspective of Survivors and Families
Authors: Dainty Katie N , Seaton Bianca , Verbeek Richard
Published: July 2021

Background:
Of those victims that are discharged alive following sudden cardiac arrest (SCA), the five-year survival rate is upwards of 75%. However, the survivor experience of “living” and their quality of life after such a life-changing event can be quite variable. Unfortunately traditional outcome measures in the SCA literature make gross, snapshot assumptions about what constitutes a “good” outcome and rarely account for life after hospital discharge. The objective of this study was to understand the survivor and family/caregiver experience of life after SCA and what outcomes are important to them as “life goes on”.

Methods:
In-depth qualitative interviews were conducted with survivors and their families/caregivers at various stages of survival. Survivors and family members were interviewed together and separately. The interviews focused on concepts such as what their recovery journey was like, what long-term issues were most important to them and how we might implement measures of such concepts into more research and practice. Interviews were audio-taped, transcribed verbatim and analyzed by the authors using constant comparative thematic analysis techniques.

Results:
During in-depth interviews with more than 30 survivors and caregivers we heard that despite being a relatively high functioning group, their lives have been deeply affected by their cardiac arrest experience. They spoke about the importance of both psychologic and physical recovery and the influence of latent depression, anxiety, memory-loss, fatigue, infertility, changes in body image and relationships with loved ones. For some there have also been unique challenges with having an implanted cardiac defibrillator (ICD). Spouses/family members spoke about the caregiver burden, anxiety around their loved ones health and the impact of not having any sense of what to expect after discharge.

Conclusions:
The psycho-social type outcomes identified as very influential by survivors and families are almost entirely unmeasured in the resuscitation literature. This robust qualitative work gives us important insight that we hope to use to design more survivor-centred outcome measures for prospective use in research and practice. (*Abstract will be co-presented with an SCA survivor)
Abstract 134: Patients’ Perspectives on Enrollment in Research Using the Exception From Informed Consent: An Integrated Survey
Authors: Dickert Neal W , Biros Michelle H , Harney Deneil K , Jones Elizabeth B , Mitchell Andrea R , Scicluna Victoria M , Silbergleit Robert , Speight Candace D , Wright David W , Pentz Rebecca D
Published: July 2021

Introduction:
Relatively minimal data exist regarding perspectives of patients (or surrogate decision-makers) after enrollment in clinical trials using the exception from informed consent (EFIC) for emergency research, a regulation essential for resuscitation research. Prior studies have shown that attitudes are generally positive but have enrolled a small proportion of participants and may have been subject to selection bias.

Methods:
As part of the study protocol, a 10-item paper-and-pencil survey was integrated into the protocol for all sites of the Established Status Epilepticus Treatment Trial (ESETT) trial, a randomized trial of three treatments for benzodiazepine-refractory status epilepticus in pediatric and adult patients. All patients (or surrogate) were given the survey after being asked for consent to continue in ESETT. Primary domains included acceptance of trial enrollment, acceptance of EFIC, and views on which population to include in community consultation. Response items primarily used a 5-point Likert scale. Simple descriptive statistics were tabulated.

Results:
In total, 317 of 443 patients/surrogates completed the survey (71.6% response). Only 7.3% (23/317) disagreed with the statement “I am glad that my family member/I was included in the ESETT research study,” and 24.9% (79/317) disagreed with being included under EFIC. When asked whom researchers should consult during community consultation, 81.1% (257/317) said patients who have had seizures, 64.7% (205/317) said their family members, and individuals at particular risk for seizures (50.8%) (161/317) were most frequently chosen. Only 26.5% (84/317) felt that members of the general public should be consulted.

Conclusions:
This is the largest study to date of participants’ perspectives on being enrolled in an EFIC trial. Rates of enrollment acceptance were relatively high; acceptance of EFIC specifically was slightly lower. There is much greater support for consulting individuals with connections to the disease under study than the general public or other groups. These findings further suggest that targeted community consultation may be appropriate and the importance of clear communication with participants after enrollment regarding reasons for EFIC use.
Abstract 14: Polyethylene Glycol-20k Improves Post-Resuscitation Cerebral Microcirculation in a Rat Model of Cardiac Arrest
Authors: Guo Qinyue , Yang Jin , Hu Zhangle , Xiao Yan , Wu Xiaobo , Bradley Jennifer , Peberdy Mary Ann , Ornato Joseph , Mangino Martin , Tang Wanchun
Published: July 2021

Introduction:
Polyethylene glycol-20k (PEG-20k) reduces severity of post CPR cerebral dysfunction, however the mechanism is yet unproven. In other vascular beds, PEG-20k osmotically reverses ischemia-induced metabolic cell swelling and decompresses the microcirculation, which improves flow and oxygen transfer.

Hypothesis:
We hypothesized that PEG-20k improves neurologic function by preserving microcirculatory blood flow and decreasing brain swelling.

Methods:
32 S-D rats weighting between 450-550g were randomized into 4 groups: 1) Control (CPR+SALINE); 2) Treated (CPR+PEG-20k); 3) NO CPR+SALINE; 4) NO CPR+PEG-20k. CPR was initiated after 8 min of untreated ventricular fibrillation and continued for 8 min, then defibrillation was performed. PEG-20k was administered at the beginning of chest compression. Cerebral microcirculation was visualized at baseline, 2, 4 and 6 h after CPR by side-stream dark-field (SDF) imaging with a 5х imaging objective. Animals were euthanized with Euthasol (150 mg/kg) and brain swelling was assessed by comparing wet-to-dry weight ratios at 6h post resuscitation.

Results:
The wet to dry ratio in the CPR+SALINE group was significantly higher than the other three groups (p<0.05). PEG-20k attenuated the wet to dry ratio (p<0.05) compared with the CPR+SALINE group (Fig 1). A significant improvement of cerebral microcirculation was also observed in the CPR+PEG-20k group when compared with the CPR+SALINE group (Fig 2).

Conclusions:
PEG-20k given during resuscitation improves cerebral microcirculatory flow by increasing microcirculation and decreasing brain tissue swelling in a rat model of CA.
Abstract 143: Electrocardiographic Changes Preceding In-Hospital Cardiac Arrests From Pulseless Electrical Activity / Asystole Provide Insights into Underlying Cause and Pathophysiology
Authors: Yang Jason J , Do Duc H , Hu Xiao , Boyle Noel G
Published: July 2021

Introduction:
Survival from in-hospital cardiac arrests (IHCA) due to pulseless electrical activity (PEA) or asystole remains extremely poor. Our understanding of the pathophysiology of PEA is limited, and management of IHCA largely follows a “one size fits all” approach due to the lack of reliable methods to determine underlying cause in real-time.

Hypothesis:
Changes on continuous electrocardiogram (ECG) preceding IHCA reflect the underlying cause and pathophysiology of IHCA.

Methods:
We evaluated adult patients with IHCA from PEA/asystole at a tertiary care hospital between 3/2010 - 8/2014 with at least 3 hours of continuous ECG data preceding IHCA. We determined the likely cause of IHCA by reviewing of clinical, lab, imaging, and autopsy data. We analyzed up to 24 hours of continuous ECG data evaluating for changes in rhythm, PR interval, QRS and ST/T wave morphology leading up to IHCA.

Results:
Eighty-nine patients were studied (mean age 62 ± 18 years, 54% male). Return of spontaneous circulation was obtained in 65 (73%) and 24 (27%) survived to discharge. We found 5 distinct patterns of ECG changes leading up to and including the arrest rhythm (Table). Causes of cardiac arrest were significantly different between the group (Fischer’s exact p<0.001). Notably, a severe right ventricular strain ECG pattern was found preceding PEA caused by pulmonary embolism, asphyxia from large mucus plugs or massive aspiration, acute respiratory distress syndrome, and cardiogenic shock with biventricular failure.

Conclusion:
Distinct patterns of changes in rhythm and ECG morphology which reflect different underlying causes and pathophysiology of IHCA were identified. Recognition of these patterns may provide an opportunity for better understanding of PEA mechanisms and outcomes, and allow for real-time prediction of IHCA cause to help direct management.
Abstract 145: Efficacy of ECG Waveform to Predict Outcome in Patients With Out-of-Hospital Cardiac Arrest
Authors: Yoshioka Ryozo , Narita Chihiro , Haruta Koichi , Miyakawa Kyuhei , Maki Nobuyuki , Miyake Akihiro , Tosaka Naoki , Yoshida Hiroshi , Nonogi Hiroshi
Published: July 2021

Introduction:
Neurological intact survival of pulseless electrical activity (PEA) has extremely poor outcome when compared with ventricular fibrillation. In Japan, the all patients with out-of-hospital cardiac arrest received CPR is transferred to emergency hospitals. To determine termination of resuscitation, it is necessary to predict their outcome. Therefore, we analyzed the relationship between ECG changes during prehospital resuscitation and outcome.

Method:
This study is a retrospective observational study for out-of-hospital PEA in April 2012 - April 2017 which was transported to the emergency medical center in Shizuoka General Hospital. We examined consecutive PEA cases where recorded by emergency medical services. The QRS width and RR interval were measured in ECG recording in the initial check pulse phase and arrival hospital. The primary outcome was survival admission and the secondary outcome was good neurologic outcome defined as cerebral performance score (CPC) of 1, 2. ECG changes determined as QRS width and RR interval in initial rhythm minus those at hospital arrival.

Results:
Eighty-four patients were analyzed and the average age was 77.3 years old, male 52.0%. There were 44 cases (52%) with survival admission (ROSC cases) and 7 (8%) with CPC 1-2. ROSC cases showed significantly narrower QRS width than non-ROSC cases in the initial waveform (139.1±61.9 vs 165.5±57.5msec, P<0.05). Regarding ECG waveform changes, RR interval was significantly shortened in ROSC cases(-356.0±1256.0 vs 386.8±1258.6msec, P<0.01). Comparing CPC1-2 cases and CPC3-5 cases, QRS width is significantly narrower in CPC1-2 cases(108.6±44.51 vs 155.6±60msec, P<0.05), and there were no significant differences in ECG waveform changes. Multivariate analysis revealed that Initial QRS width and RR interval change are the independent factors associated with survival admission.

Conclusion:
Those findings suggested that analyzing QRS width and change of RR intervals during prehospital resuscitation predict survival admission in PEA cases.
Abstract 146: Association Between Quantitative Waveform Measures of the Ventricular Fibrillation Electrocardiogram and Defibrillation Success in the ROC ALPS Trial
Authors: Salcido David D , Schmicker Robert H , Koller Allison C , Sundermann Matthew L , Flickinger Katharyn L , Menegazzi James J
Published: July 2021

Introduction:
During out-of-hospital cardiac arrest (OHCA), features of the ventricular fibrillation electrocardiogram (ECG) have been correlated with outcomes. Understanding factors affecting the variability of these features may elucidate their utility. We examined the association between quantitative waveform measures (QWM) of the VF ECG and defibrillation success in the context of the Resuscitation Outcomes Consortium (ROC) amiodarone, lidocaine and placebo (ALPS) trial.

Methods:
We retrospectively obtained case data for patients enrolled in the ALPS trial from the ROC data coordinating center (DCC). The primary trial enrolled emergency medical services (EMS) – treated OHCA patients with at least one failed defibrillation from 2012 to 2015 at 10 sites across the ROC network for randomization to amiodarone, lidocaine or placebo. We included all enrolled cases with an ECG file available through the DCC. ECG signals were analyzed with custom, semi-automatic software to identify shocks, parse pre-shock ECG segments, and identify pre- and post- defibrillation rhythms, including post-shock return of organized rhythm (ROOR). Three QWM – AMSA, centroid frequency (CF), and median slope (MS) – were calculated for pre-shock ECG segments. Multivariable logistic regression models accounting for repeated shocks were constructed with outcome ROOR, adjusting for ALPS treatment arm, shock number and relevant case characteristics.

Results:
A total of 1242 cases were available for analysis, comprising a total of 5,408 defibrillation events with identifiable pre-shock VF. Mean (SD) QWM values for all shocks were: AMSA{6.74 (10.80)}, CF{3.98 (1.68)} , MS{0.02 (0.02)}. CF, but not AMSA or MS, differed significantly between ALPS treatment arms when controlling for shock number (p
amio
< 0.001; p
lido
= 0.016). All QWM were significantly directly associated with defibrillation success in multivariable models (OR
AMSA
=1.03 [95%CI: 1.02 – 1.04]; OR
CF
=1.35 [95%CI: 1.26 – 1.45]); OR
MS
=1.05 [95%CI: 1.04 – 1.06]).

Conclusions:
In the ROC ALPS trial, QWM were associated with defibrillation success independent of shock number or treatment arm.
Abstract 148: The Time Interval Between the R-Wave and Maximum Aortic Pressure Affects Chest Compression Hemodynamics in a Swine Model of Pseudo Electro-Mechanical Dissociation
Authors: Lampe Joshua W , Moodie Karen L , Gould Jeffrey R , Kaufman Christopher L , Paradis Norman A
Published: July 2021

Introduction:
The prevalence of pseudo electro-mechanical dissociation (P-EMD) as an initial cardiac arrest state is increasing. P-EMD manifests a weak ventricular contraction, which is not sufficient to sustain life. However, the presence of a weak ventricular contraction may lead to interference with or synergy with the blood flow generated by a chest compression depending on the time interval between the compression and ventricular contraction.

Hypothesis:
We hypothesize that the interval between a chest compression and the ventricular contraction during P-EMD will influence the hemodynamics created by the chest compression.

Methods:
Using our well established hypoxic P-EMD model, we measured blood pressures and ECG during mechanical chest compression (100 CPM, 2”). A nearest-neighbor analysis determined the time interval between the R-wave and the peak aortic pressure, defined as t
peak AOP
- t
Rwave
. Peak aortic pressures that had more than one R-wave nearest neighbor were excluded. 1,497 chest compressions were analyzed. Intervals were divided into quartiles, and hemodynamic parameters were compared between the quartiles using a repeated measure ANOVA with Bonferroni correction.

Results:
Interval (int) quartiles were defined as: Q1: int > 100 ms; Q2: 100 ms > int > 0.0 ms; Q3: 0.0ms > int > -90 ms; Q4: - 90 ms > int. Mean arterial pressures (MAP) in mmHg as a function of interval are: Q1: 33.8±0.6; Q2: 41.1±0.6; Q3: 38.3±0.6; Q4: 33.1±0.6. The MAP value for compressions with an interval in Q2 was higher than the other quartiles (
p
> 0.05). Coronary perfusion pressures (CPP) in mmHg as a function of interval are: Q1: 11.7±0.5; Q2: 15.3±0.5; Q3: 15.6±0.5; Q4: 12.9±0.5. The CPP values for compressions with an interval in Q2 or Q3 was higher than the other quartiles (
p
> 0.05).

Conclusions:
The interval between the R-wave and the peak aortic pressure generated by a chest compression has a significant effect on the resulting hemodynamics. Shorter intervals, both positive and negative are associated with improved blood pressures during resuscitation from P-EMD. These data suggest that delivery of standard CPR during P-EMD can result in a mix of effective and less effective compressions.
Abstract 149: Role of Pre and Intra-Arrest Hemodynamics in Evolution of the Ventricular Fibrillation Electrocardiogram Waveform
Authors: Kern Caelie E , Salcido David D
Published: July 2021

Purpose:
Quantitative waveform measures (QWM) of the ventricular fibrillation (VF) waveform have been shown in laboratory and clinical studies to be predictive of return of spontaneous circulation (ROSC) and survival to hospital discharge. During resuscitation, QWM are responsive to hemodynamic changes resulting from CPR. It is not known whether the trajectory of QWM are affected by pre-arrest hemodynamics or intra-arrest arterio-venous pressure equilibration. We sought to investigate the role of hemodynamics on the evolution of VF before and during prolonged VF.

Methods:
We pooled data from six previous porcine experiments. Each modeled prolonged VF and included electrical induction of VF which was left untreated for up to 10 minutes, followed by attempted resuscitation. All animals were instrumented with pressure transducers (Millar, MikroTip) placed via femoral cutdown in the aorta and right atrium, as well as Lead II surface ECG. Signals were recorded continuously at 1000Hz with a data acquisition unit (PowerLab, ADInstruments). Mean baseline central arterial (CAP) and central venous pressure (CVP) were calculated from 1- minute of immediate pre-VF pressure traces. Coronary perfusion pressure (CPP) during untreated VF was calculated as the continuous difference between the CAP and CVP channels. Median slope (MS), a QWM, was calculated in 1-second windows and interpolated to the full length of the intra-arrest ECG. For trajectory analysis, CPP and MS traces were normalized on a 0-1 scale and grouped by morphological similarity. Pearson’s Correlation coefficient was calculated between corresponding CPP and MS traces.

Results:
A total of 141 experiments were included in the analysis. Overall mean (SD) correlation between CPP and MS was 0.56 (0.29). CPP-MS correlation strength did not correlate with baseline pressures. However, trajectory analysis revealed multiple patterns of hemodynamic and QWM evolution through untreated VF, with the most well-defined (mean coeff. = 0.58) indicating a shared bimodality temporally offset between CPP and MS.

Conclusions:
Hemodynamics during untreated VF show some correlation with the trajectory of QWM of the VF signal. More work is needed to understand the mechanism of this relationship.
Abstract 15: Repopulation of CA1 Region in the Hippocampus is Accompanied by Increased Diameter and Reduced Glial Scarring After 20 Weeks of Survival in an 8 Min Ventricular Fibrillation Cardiac Arrest Rat Model
Authors: Weihs Wolfgang , Ettl Florian , Magnet Ingrid A , Warenits Alexandra M , Herkner Harald , Holzer Michael , Janata Andreas , Högler Sandra
Published: July 2021

Background:
The CA1 region of hippocampus is specifically vulnerable to global ischemia and is depopulated 14 days after 8min ventricular fibrillation cardiac arrests (VF-CA) and conventional resuscitation in a rat model. We have previously reported on the pyramidal cell repopulation of the CA1 region after long term survival after cardiac arrest in two thirds of animals. (Circulation. 2014;130:A80) The aim of this study was to investigate the distribution of microglia and astrocytes in the CA1 region of rat hippocampus after CA and to measure its diameter.

Methods:
After 8 min of VF-CA male Sprague-Dawley rats received mechanical chest compressions for 2 min and epinephrine 20 μg/kg. The animals were defibrillated thereafter every 2 min to achieve return of spontaneous circulation. Animals surviving with favorable neurologic recovery were sacrificed 140 days after CA (n=12, 8 with neuronal repopulation (R), 4 without R (nonR)) and compared to 14 day survivors (n=6) and control animals (n=20).

Results:
Microglia cells/ 75000μm
2
were 6±3 in controls, 53±9 in 14d survivors (p<0.001 vs controls), 12±4 in 140d-R and 19±12 in 140d-nonR. Astrocytes/75000μm
2
were 9±2 in controls, 15±3 in 14d survivors (p<0.001 vs controls), 21±4 in 140d-R and 43±13 in 140d-nonR animals (p<0.001 vs 140d-R). The hippocampal diameter (μm) was 543±36 in controls, 417±36 in 14d survivors (p<0.001 vs controls), 462±39 in 140d-R and 306±86 in 140d-nonR animals (p<0.001 vs 140d-R).

Conclusions:
The repopulation of pyramid cells in the CA1 that has taken place in two thirds of animals is accompanied by a significant increase in the diameter of the hippocampus and reduced astrocyte numbers compared to nonR-animals. Numbers of microglial cells are significantly increased after 14d survival removing cell debris after neuronal damage. This lifelong potential of the hippocampus for repair due to adult neurogenesis may open an additional late phase therapeutic window for CA recovery.
Abstract 155: Effect of the 2010 CPR Guidelines for Patients With Out-of-Hospital Cardiac Arrest Due to Shockable Rhythm
Authors: Watanabe Yoji , Yagi Tsukasa , Nagao Ken , Tani Shigemasa , Tachibana Eizo , Chiba Nobutaka , Ashida Tadashi , Yonemoto Naohiro , Takayama Morimasa , Nonogi Hiroshi , Matsumoto Naoya , Okumura Yasuo
Published: July 2021

Background:
The 2010 guidelines have stressed that systematic post-cardiac arrest care after return of spontaneous circulation (ROSC) can improve the likelihood of patient survival with good neurological outcome. Especially, the 2010 guidelines recommended that comatose adult patients with ROSC after out-of-hospital ventricular fibrillation (VF) cardiac arrest should be induced therapeutic hypothermia (Class I). However, it is unknown whether the post-cardiac arrest care which was recommended by the 2010 guidelines contributed to favorable neurological outcome. The aim of the present study was to clarify the effects of the 2010 guidelines in patients with ROSC after cardiac arrest due to shockable rhythm, using the data of the All-Japan Utstein Registry, a prospective, nationwide, population-based registry of out-of-hospital cardiac arrest (OHCA).

Methods:
From the data of this registry between 2005 and 2015, we included adult patients with ROSC after out-of-hospital shockable cardiac arrest due to cardiac etiology. Study patients were divided into three groups based on the different CPR guidelines; the era of the 2000 guidelines (2000G), the era of the 2005 guidelines (2005G), and the era of the 2010 guidelines (2010G). The primary endpoint was favorable neurological outcome at 30 days after OHCA.

Results:
The 30,518 patients who met the inclusion criteria comprised 24,729 with ROSC before arrival at the hospital and 5,789 with ROSC after hospital arrival without prehospital ROSC. Figure showed favorable neurological outcome at 30 days in the three groups. Moreover, multivariable analysis showed that the 2010 guidelines were an independent predictor of favorable neurological outcome at 30 days after OHCA, respectively (Figure).

Conclusion:
In the patients with ROSC after out-of-hospital shockable cardiac arrest, the 2010 guidelines were superior to the 2005 guidelines and the 2000 guidelines, in terms of neurological benefits.
Abstract 156: Which Factors Promote Transition From PEA to Spontaneous Circulation and PEA Recurrence in Children?
Authors: Nordseth Trond , Niles Dana , Eftestøl Trygve , Irusta Unai , Kvaløy Jan T , Nadkarni Vinay , Sutton Robert , Berg Robert , Abella Benjamin S , Skogvoll Eirik
Published: July 2021

Background:
Pediatric cardiac arrests are relatively rare outside specialist centres, and may differ in several ways from adults. The aim of this study was to investigate factors that may impact on the transition from Pulseless electrical activity (PEA) to Return of spontaneous circulation (ROSC), or recurrence of PEA from ROSC, in children and adolescents.

Methods:
We prospectively registered resuscitation episodes in a pediatric hospital over a period of 3 years, using defibrillators that can register CPR variables like chest compression depth and rate, and ventilation rate. ROSC was defined as an organized electrical rhythm without chest compressions >= 1 minute. CPR variables, patient characteristics and etiology, and dynamic covariates (e.g. the proportion of time spent in PEA or ROSC) were entered as univariate predictors of the transition intensity between PEA and ROSC or the reverse. Statistical anlysis was done with using Aalen’s additive regression model, a variant of survival analysis.

Results:
In 64 cardiac arrest patients (median age 15, range 2-22 years), there were 49 transitions from PEA to ROSC, and 25 recurrences of PEA from ROSC. Identified factors favoring a transition from PEA to ROSC include greater mean compression depth (p=0.010), higher weight (p=0.006), and lower proportion of PEA for the last 5 minutes (p=0.001). PEA recurrence from ROSC was also associated with greater mean compression depth (p=0.006) and higher weight (p=0.021). However, respiratory etiology was negatively associated with PEA recurrence (p=0.007). Immediate effects (i.e. the last 1-minute average) were more pronounced than 3-minute average effects. Dynamic covariates, which capture the course of the individual patient (e.g. cumulative time in PEA or in ROSC, number of transitions), were strongly associated with the transitions.

Conclusion:
Some event variables (compression depth, patient weight) were associated with transitions between PEA and ROSC in both directions, and a respiratory etiology appears to protect against PEA recurrence. Dynamic covariates impact on the likelihood of transitioning from PEA to ROSC or PEA recurrence.
Abstract 159: Epinephrine Increases Cerebral Perfusion and Oxygenation in a Pre-Clinical Model of Pediatric In-Hospital Cardiac Arrest
Authors: Mavroudis Constantine D , Ko Tiffany S , Morgan Ryan W , Hefti Marco M , Landis William P , Boorady Timothy W , Marquez Alexandra M , Karlsson Michael , Licht Daniel J , Nadkarni Vinay M , Berg Robert A , Sutton Robert M , Kilbaugh Todd J
Published: July 2021

Introduction:
Despite controversies, epinephrine remains a mainstay of CPR. Recent animal studies have suggested that epinephrine may decrease cerebral blood flow (CBF) and cerebral oxygenation, possibly potentiating neurological injury during CPR. We investigated the cerebrovascular effects of intravenous epinephrine in a swine model of pediatric in-hospital cardiac arrest.

Hypothesis:
Epinephrine will increase CBF and cerebral oxygenation during CPR.

Methods:
One-month old piglets (n=20, 8-10kg) underwent asphyxia for 7 minutes, VF, and CPR according to AHA guidelines for 10-20 minutes. Epinephrine boluses (20 mcg/kg) were administered at minutes 2, 6, 10, and 14 of CPR. Invasive (laser Doppler) and noninvasive (diffuse optical) continuous measurements of CBF and oxygenation were recorded. Wilcoxon Rank-Sum test was used to compare measurements 15 seconds prior to epinephrine doses to sequential measurements at 1-minute intervals following epinephrine; data are described as median [IQR].

Results:
Compared to pre-epinephrine values, CBF was most significantly increased one minute after the first dose of epinephrine (noninvasive: +37.7% [6.1, 79]; invasive: +24% [-0.3, 118], p<0.004 for both) and returned to baseline by 3 minutes post-epinephrine. Cerebral tissue oxygenation was also most significantly increased one-minute after the first dose of epinephrine (noninvasive: +25.2% [9.0, 45]; invasive: +160% [30.3, 428], p<0.001 for both) and remained elevated 4 minutes post-epinephrine. Effects were also significant one minute following the second dose on CBF (noninvasive: +11.5% [4.5, 29]; invasive: +9.5% [0.6, 19, p<0.03 for both) and on cerebral tissue oxygenation (noninvasive: +12.3% [1.6, 19]; invasive: +17.8% [-2.3,34, p<0.037 for both). There was no significant effect on any parameter following the third and fourth doses.

Conclusions:
In a swine model of pediatric in-hospital cardiac arrest, bolus-dosed epinephrine increases CBF and cerebral tissue oxygen saturation. These effects are only significant following the first two doses. Our findings are underscore the importance of further research to elucidate the transient pharmacodynamics of epinephrine to optimize both survival and neurological outcomes.
Abstract 160: End-Tidal Carbon Dioxide > 20mmHg During Pediatric In-Hospital Cardiopulmonary Resuscitation is not Associated With Survival
Authors: Berg Robert A , Reeder Ronald W , Meert Kathleen L , Yates Andrew R , Berger John T , Newth Christopher J , Carcillo Joseph A , McQuillen Patrick S , Harrison Rick E , Moler Frank W , Pollack Murray M , Carpenter Todd C , Notterman Daniel A , Holubkov Richard , Dean Michael , Nadkarni Vinay M , Sutton Robert M
Published: July 2021

Introduction:
Based on laboratory CPR investigations and limited adult data, the American Heart Association Consensus Statement on CPR Quality recommends titrating end-tidal carbon dioxide (ETCO2) to > 20 mmHg during CPR.

Hypothesis:
ETCO2 > 20 mmHg during pediatric in-hospital CPR is associated with survival to hospital discharge.

Methods:
Children > 37 weeks gestation in Collaborative Pediatric Critical Care Research Network intensive care units with chest compressions for > 1 minute and ETCO2 monitoring prior to and during CPR between July 1, 2013 and June 31, 2016 were included. ETCO2 and Utstein-style cardiac arrest data were collected. Multivariable Poisson regression models with robust error estimates were used to estimate relative risk of outcomes.

Results:
Investigators blinded to outcome analyzed ETCO2 waveforms from 43 children for the first (up to) 10 minutes of CPR. During CPR, the median ETCO2 was 23 mmHg (quartiles, 16 and 28 mmHg), median ventilation rate was 29 breaths/minute (quartiles, 24 and 35 bpm), and median duration of CPR was 5 minutes [quartiles, 2 and 16 minutes]. Return of spontaneous circulation occurred after 71% of CPR events and 37% of patients survived to hospital discharge. For children with mean ETCO2 during CPR > 20 mmHg, the adjusted relative risk for return of spontaneous circulation was 1.32 (0.89, 1.95), p= 0.16 and for survival to hospital discharge was 0.92 (0.41, 2.08), p= 0.84. Further sensitivity analyses were unable to demonstrate an association between mean ETCO2 > 25 mmHg or > 30 mmHg and ROSC or survival to hospital discharge. The median mean ETCO2 among children who survived to hospital discharge was 20 mmHg [quartiles; 15, 28 mmHg] versus 23 mmHg [16, 28 mmHg] among non-survivors.

Conclusion:
Mean ETCO2 > 20 mmHg during pediatric in-hospital CPR was not associated with ROSC or survival to hospital discharge. ETCO2 was not demonstrably different among survivors versus non-survivors.
Abstract 162: Major Differences in the Intended Operation and Default Energy Setting in Automated External Defibrillators in Pediatric Cardiac Arrest
Authors: Budolfsen Cecilie , Nguyen Dung T , Lauridsen Kasper G , Stærk Mathilde , Schmidt Anders S , Løfgren Bo
Published: July 2021

Introduction:
Automated external defibrillators (AEDs) should be easy to use to improve survival from cardiac arrest. In pediatric cardiac arrest, defibrillation is recommended to be delivered with less energy compared with adults. Consequently, many AED manufacturers provide the possibility of “converting” an AED from adult to pediatric use.

Aim:
To study how different AEDs are intended to be operated in case of pediatric cardiac arrest and to investigate the default pediatric defibrillation energy levels.

Methods:
This nationwide cross-sectional study included information on all commercially available AEDs sold to laypersons in Denmark. Technical specifications and information on AED use in pediatric cardiac arrest were extracted from user manuals, data sheets, and from contact with AED distributors in Denmark.

Results:
Overall, 28 different AEDs were available in Denmark. Data on pediatric use were available for all 28 (100%) devices. Separate pediatric electrodes were required for 19 (68%) AEDs which were sold as an accessory. Activation of “pediatric mode” was available in 10 (36%) AEDs leading to an automatic adjustment of shock energy level thereby making the use of adult electrodes in children possible. This feature consisted of a “pediatric button” in 8 (29%) devices and 1 (4%) device required insertion of an accessory “child key”. Data on default energy levels were available for 27 (96%) of devices. Median first shock energy level was 50J (Q1; 50J, Q3; 50J) with a range from 15-50J. Median third shock energy level was 50J (Q1; 50J, Q3; 83.5J) with a range from 50-140J.

Conclusion:
There are major differences in the intended operation and default energy settings in automated external defibrillators used in pediatric cardiac arrest. Standardizing how AEDs should be operated in pediatric cardiac arrest may reduce the risk of human errors and improve survival.