bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 255: Analysis of Out-of-Hospital Cardiac Arrest in Infants, Children and Adolescents in the Kyushu Area in Japan by Locally Obtained Data
Authors: Yoshinaga Masao , Ishikawa Shiro , Shida Masanori , Hoshiko Kiyomi , Mochinaga Shunichi , Nishihara Shigetaka , Shimada Susumu , Takamura Kazushi , Honjo Shigeru , Ganaha Hitoshi , Sunagawa Makoto , Nakarai Toshiko
Published: July 2021

Background:
The Fire and Disaster Management Agency of Japan launched a population-based cohort study of patients suffering from OHCA in 2005. However, more detailed data on each OHCA case may be required to determine any confounders present in each area to prevent locally occurring OHCA.

Methods and Results:
The Council for School-Based Screening Programs of the Kyushu Medical Associations started to obtain data of each case of out-of-hospital cardiac arrest (OHCA) <20 years of age from school boards, school physicians, and local fire departments in the Kyushu area in 2012 using a questionnaire. The questionnaire asked information used in the Utstein form and more detailed situations about OHCA cases. In logistic regression analysis, age, sex, the location of OHCA (at home or not at home), the timing of OHCA (during sleep or not during sleep), the presence of resuscitation, and the use of an AED were used as dependent variables. Sixty-seven cases of OHCA were obtained in 2002 and 2003. The prevalence of OHCA in each Prefecture corresponded to 0.29 to 4.17 per 100,000 subjects (Okamoto et al. Circ J, 2013), indicating that less than half of the annual cases in Kyushu area were obtained. Of 67 cases of OHCA, 20, 7, 13, and 27 cases occurred in those aged 0, 1-5, 6-12, and 13-18 years, respectively. Of 40 cases of OHCA that occurred at home, 37 (93%) were fatal. Among 20 infant cases, 16 (80%) occurred during sleeping. Of 27 young adolescent cases, 5 were found dead in the bath. In logistic regression analysis, OHCA occurring at home was a sole predictive factor for death (p=0.000, 95% confidence interval: 4.4-73.1).

Conclusions:
To improve the prevalence and outcome of OHCA cases in the pediatric population, information on resuscitation should be provided to parents. New strategies for sudden infant death during sleeping should be examined, such as electrocardiographic screening at 1 month old (Schwartz PJ, et al. Circulation, 2009: Yoshinaga M, et al. Circ Arrhythm Electrophysiol, 2013). Bathing is at high risk of OHCA, not only in the elderly population, but also in the young population.
Abstract 258: Did We Already Reach the Best Achievable Quality of Chest Compression in Vienna?
Authors: Zeiner Sebastian
Published: July 2021

INTRODUCTION:
Annually ~45 citizens per 100,000 have no signs of circulation and are assessed by teams of the Vienna Ambulance Service. Only in 25 percent of these cases sustained return of spontaneous circulation (ROSC) is achieved and merely unsatisfying 11.3 percent leave the hospital again.

The goal of this project is to follow up on chest compression performances of the ambulance crews in Vienna after the Circulation Improving Resuscitation Care (CIRC) Trial some years ago.

METHODS:
This observational trial assesses the quality of chest compression based on the guideline recommendations. Data are gathered from run-reports and written event recordings as described by the Utstein criteria including command and control center and emergency call records, ECG, thoracic impedance data, vital parameters as well as hospital records. During the collection of this data, the ambulance service of Vienna received standardized feedback on their CPR performance.

RESULTS:
From
August
1, 2013 to April 30, 2014701 patients were registered. MedianCompression ratewas 108/min.Median fraction of time in which chest compression were given with the target rate of 100 to 120/min, per case is 75% and median hands on fraction was 82%.Mean percentage of minutes with a hands off fraction of 75 or higher is 72% (SD ± 24). Comparing the group who regained ROSC to those who did not no significant difference can be found in either hands on fraction as well as frequency. The confidence interval of hands on fraction within the group that regained ROSC is between 75% and 80% compared to 74% and 78% within the group that did not.

CONCLUSION:
The missing presence of any difference between the groups with regained ROSC and the one that did not leads to the conclusion that the quality of chest compression is on overall high level and further improvement is hardly possible and will most likely not lead to further more ROSC.
Abstract 261: Intermittently Encouraging Laypersons to Practice CPR Does Not Improve CPR Quality, Whereas Actual Practice Does Improve CPR Quality, 6 Months Post Training
Authors: Blewer Audrey L , Buckler David G , Li Jiaqi , Leary Marion , Becker Lance B , Groeneveld Peter W , Putt Mary E , Nadkarni Vinay M , Abella Benjamin S
Published: July 2021

Background:
CPR quality varies considerably and skills deteriorate over time from initial training. Investigations suggest that frequent training may improve CPR skills. Few studies have tested methods to encourage laypersons to practice their skills post-training.

Objectives:
We hypothesized that trained laypersons who receive intermittent encouragement to practice their CPR skills will perform faster and deeper chest compressions (CC); additionally, we hypothesized that those who actually practiced their skills will have improved CPR quality when tested 6 months post-training.

Methods:
In a multicenter trial of CPR strategies, cardiac patient caregivers were trained in CPR. All subjects were contacted at 2 and 4 months post-training and randomized to receive encouragement to practice CPR (“prompting”) or no suggestion to practice (“no prompting”) via a self-reported method (telephone, email, etc). At 6 months post-training, CPR skills were assessed through a “surprise” home visit and subjects were asked if they practiced their skills. CPR performance was quantified on a CPR-manikin and analyzed using multivariable regression controlling for confounders.

Results:
Subjects were enrolled from 02/2012-05/2014. 398 subjects consented to a skills check (180 in the prompting group, 183 in the control group, 35 lost to follow-up). Enrollees’ mean age was 51±14 years, and 73% were female. In an adjusted regression analysis, CC depth was 2.6±3.1 mm deeper among the prompted cohort (p=ns) and CC rate was 0.7±6.3 per min faster among those prompted (p=ns). Of those prompted, 56% reported practicing after prompting, while 44% of those not prompted reported practicing CPR skills after training. CC rate was 1.7 ± 3.2 per min faster among those who practiced their skills (p=ns). CC depth was 5.0 ±1.6 mm (95% CI: 1.8, 8.2) deeper among individuals who practiced their skills compared to those who did not practice (p<0.01).

Conclusions:
Intermittent encouragement using self-reported preferred contact methods did not improve CPR quality, while CC depth improved among laypersons that actually practiced their skills. This work suggests that practicing improves CC depth and additional efforts are needed to facilitate practicing post-training among laypersons.
Abstract 267: Inhaled Nitric Oxide Lowers Pulmonary Artery Pressure During Cardiopulmonary Resuscitation but Does Not Increase Survival in a Model of Prolonged Cardiac Arrest in Pigs
Authors: Derwall Matthias , Ebeling Andreas , Brücken Anne , Fries Michael
Published: July 2021

Introduction:
We have previously shown that thoracic chest compressions during cardiac arrest (CA) result in elevated pulmonary vascular resistance (PVR), potentially impeding a return of spontaneous circulation (ROSC) by limiting circulation.

Hypothesis:
Applying inhaled nitric oxide (iNO) will lower PVR during cardiopulmonary resuscitation (CPR).

Methods:
8 pigs were instrumented with an arterial line and a pulmonary artery catheter. CA was electrically induced and left untreated for 10 minutes before CPR was performed employing mechanical chest compressions and mechanical ventilation. Animals were randomized to either receive 20ppm of iNO (n = 3, iNO) or 100% Oxygen (n = 5, Control) during CPR. After 6 minutes of CPR, defibrillation was attempted. When no ROSC was achieved, chest compressions were restarted and continued for up to 30 minutes.

Results:
Mean pulmonary artery pressure (MPAP) rose significantly from 9 ± 4 following 10 minutes of VF to 21 ± 7 mmHg following 1 minute of CPR in Control animals (p=0.01). Animals receiving iNO showed a significantly lesser increase in MPAP from 5 ± 1 following 10 minutes of VF to 8 ± 3 mmHg following 1 minute of CPR (p=0.18). While MPAP did not differ on baseline or during 10 minutes of VF, iNO treatment resulted in significantly lower MPAP values averaged over the first 6 minutes of CPR (10 ± 1 vs. 22 ± 1 mmHg, p<0.01 ; see Figure ; * indicates p<0.01 for MPAP iNO vs. Control). This was reflected by similar changes in PVR, which remained significantly lower in iNO treated animals during CPR (80 ± 9 vs. 188 ± 17 dyn x sec x cm-5, p<0.01). While no animal achieved ROSC in the iNO group, two of the five control animals could be successfully resuscitated.

Conclusion:
Ventilation with 20ppm nitric oxide during CPR reduces MPAP and PVR following prolonged CA, but does not improve survival in these preliminary experiments. Expanding the sample size will be necessary to determine potential impact of this intervention on survival or neurocognitive outcome.
Abstract 293: Inhibition of Nitric Oxide Synthase Decreases Myocardial Injury Following Hemorrhagic Shock and Resuscitation in Rat Model
Authors: Soliman Mona
Published: July 2021

Resuscitation following hemorrhagic shock result in myocardial contractile dysfunction and injury. We examined the protective effects of non-selective inhibitor of nitric oxide synthase N(G)-nitro-L-arginine methylester (L-NAME) on myocardial contractile function in the isolated perfused hearts, after
ex vivo
as well as
in vivo
treatment with L-NAME and resuscitation following one hour of hemorrhagic shock.Male Sprague Dawley rats (300-350 gm) were assigned to 2 sets of experimental protocols:
ex vivo
and
in vivo
treatment and resuscitation. Each set has 3 experimental groups (n= 6 per group): normotensive (N), hemorrhagic shock and resuscitation (HS-R) and hemorrhagic shock rats treated with L-NAME and resuscitated (HS- L-NAME-R). Rats were hemorrhaged over 60 min to reach a mean arterial blood pressure of 40 mmHg. In the
ex vivo
group, hearts were harvested and
ex vivo
treated and resuscitated by perfused in the Langendorff System. In the L-NAME treated group, L-NAME was added for the first 5 min . Cardiac function was measured Left ventricular generated pressure and +dP/dt were calculated. In the
in vivo
group, rats were treated with L-NAME intra-arterially after 60 min hemorrhagic shock. Resuscitation was performed
in vivo
by the reinfusion of the shed blood for 30 min to restore normo-tension. Inhibition of nitric oxide synthase using L-NAME before resuscitation in
ex vivo
treated and resuscitated isolated hearts and in
in vivo
treated and resuscitated rats following hemorrhagic shock improved myocardial contractile function. Left ventricular generated pressure and + dP/dt max was significantly higher in L-NAME treated rats compared to the untreated group.Treatment with L-NAME improved left ventricular generated pressure following hemorrhagic shock in the
ex vivo
as well as the
in vivo
treated and resuscitated rats. The results indicate that L-NAME protects the myocardium against dysfunction by inhibiting NOS.
Abstract 294: Thrombolytics Improve Extracorporeal Cardiopulmonary Resuscitation After 30 Minutes of Untreated Cardiac Arrest
Authors: Spinelli Elena , Davis Ryan P , Ren Xiaodan , Iyengar Amit , Sheth Parth , Tooley Trevor , Sowell Brandon , Stacey William C , Bartlett Robert H , Rojas-Pena Alvaro , Neumar Robert W
Published: July 2021

Introduction:
Extracorporeal cardiopulmonary resuscitation (ECPR) after prolonged cardiac arrest (CA) often fails to restore cardiac and cerebral function. The primary limiting factor is presumed to be ischemia duration. An alternative hypothesis is that intravascular coagulation prevents tissue reperfusion.

Hypothesis:
Adding thrombolytics to ECPR after prolonged untreated CA improves cardiac and cerebral recovery when compared to ECPR alone.

Methods:
We developed a porcine model of 30 minute untreated ventricular fibrillation followed by ECPR for 6 hours. Animals were instrumented for hemodynamic and intracranial pressure (ICP) monitoring and continuous EEG. Two groups were studied: t-ECPR (n=7) with streptokinase 1 MU added to prime circuit; c-ECPR (n=6) with no streptokinase. ECPR goals included: flow >50 ml/kg/min, MAP >70 mmHg, PaO2 150±50 mmHg, PaCO2 40±5 mmHg, core temperature 33±1 °C. Recovery of heart function was assessed by echocardiography and weanability from ECPR. After 6 hours, animals were euthanized and brain harvested for quantification of intracerebral hemorrhage and neuronal injury.

Results:
Recovery of heart function following defibrillation occurred in 1/6 c-ECPR and 7/7 t-ECPR animals (p <0.05). Successful weaning from ECPR within 6 hours was achieved in 1/6 c-ECPR and 4/7 t-ECPR animals. Six-hour lactate clearance was significantly lower in c-ECPR than in t-ECPR (18±2 % vs 40±15 %, p <0.05). Marked increase in post-arrest ICP occurred in c-ECPR but not in t-ECPR (19±13 mmHg vs 1±3 mmHg, p <0.05). Quantitative EEG analysis revealed no recovery of brain activity in either group. Thrombolytics did not result in increased intracerebral hemorrhage (c-ECPR 0.011±0.001 % vs 0.003±0.002 % t-ECPR, p <0.05). Composite histologic damage score (scale 0 to 5) was not different between groups (c-ECPR 3.2±0.9 vs. 3.2±1.1 t-ECPR, p >0.05).

Conclusions:
Thrombolytic enhanced ECPR after prolonged untreated CA improves recovery of cardiac function and reduces brain edema without increasing bleeding. However, we detected no effect on early EEG recovery or ischemic neuronal injury. Additional studies are needed to determine if thrombolytic enhanced ECPR improves long-term survival and neurologic outcomes after prolonged CA.
Abstract 296: Views on Cardiopulmonary Resuscitation Among Older Australians in Care
Authors: Straney Lahn , Bray Janet , Mountjoy Rachel , Finn Judith
Published: July 2021

Background:
Our objective was to measure the views of older Australians on Cardiopulmonary Resuscitation (CPR).

Methods and Results:
A brief explanation of CPR and a three question survey were sent to 187 Australian residential care facilities and 34 home care providers in April 2014.

A total of 2213 respondents completed the survey, including 1943 residents from 163 residential care facilities, and 275 receiving care in the home from 24 providers (71% and 49% response rate, respectively). Respondents were mostly female (67.4%), and those in residential care were more likely to be aged over 75 years than those receiving care in the home (82.6% versus 70.4%).

The majority of respondents indicated they understood what CPR is and what it means for them (Table). Over half indicated they would want CPR if required (55.1% for residents and 65.3% for those receiving home care), this was higher among younger residents (64.2% in ≤ 75 years and 53.2% in>75 years) but similar by sex.

A large proportion believed they would fully recover after receiving CPR (44.1% of residential care and 58.1% of home care residents). Of those who agreed there was a good chance they would fully recover, almost all stated they would like to receive CPR if they had an arrest (94.8% of residential care and 91.4% of home care residents). Conversely, of those that disagreed, 98.6% of residential and 96.2% of home care respondents were unsure about or disagreed to receiving CPR.

Conclusions:
The desire for CPR in this population appears to be related to their perception as to whether or not they will fully recover. Outcomes for older people who have an arrest are typically poor. Despite this, a large proportion of respondents believed they would recover to their previous health state if they were to receive CPR. These findings highlight the need for more accurate information to inform discussions about end-of-life decisions.
Abstract 305: Remote Ischemic Postconditioning Alone and Combined with Therapeutic Hypothermia Improve Neurological Outcomes After Cardiopulmonary Resuscitation in a Porcine Model
Authors: Xu Jiefeng , Ye Sen , Li Zilong , Wang Moli , Wang Zhengquan , Chen Guofeng , Tang Wanchun
Published: July 2021

Introduction:
The degree of post-resuscitation cerebral injury is an important determinant on the outcomes for CA victims.We previously demonstrated remote ischemic pre- and post-conditioning equally attenuated post-CPR cerebral dysfunction in a rat model. Here we investigated the effects of remote ischemic post-conditioning (RIpostC) alone and combined with therapeutic hypothermia (TH) on the neurological outcomes after CPR.

Hypothesis:
RIpostC would improve post-CPR neurological function and cerebral injury, which would be enhanced by its combination with TH.

Methods:
Twenty-one male domestic pigs weighing 37 ± 2 kg were subjected to 10 mins of untreated VF followed by 5 mins of CPR. The animals were randomized to RIpostC, RIpostC+TH or control. Coincident with the start of CPR, RIpostC was induced by four cycles of 5 mins of limb ischemia followed by 5 mins of reperfusion. At 5 mins after resuscitation, TH was implemented by surface cooling to reach a temperature of 32-34 °C until 4 hrs post-resuscitation, followed by a rewarming rate of 1°C/h for 4 hrs. The resuscitated animals were observed for 72 hrs.

Results:
Six of the seven animals in each group were successfully resuscitated. Significantly better neurological function was observed in the RIpostC group than in the control group. Surprisingly the combined RIpostC and TH further improved post-CPR neurological function, which was significantly better than that in the RIpostC and control groups. There was less cerebral injury in the animals that received RIpostC alone and combined with TH; which was significantly better at 48 and 72 hrs post-resuscitation when compared to the control group. Furthermore, significantly less cerebral injury was measured at 72 hrs in the combination group than in the RIpostC group (Table).

Conclusion:
In a porcine model of CA, RIpostC significantly improved post-resuscitation neurological function and cerebral injury. Its combination with TH further enhanced its protective effects
Abstract 308: Metropolitan Police First-Responder Defibrillation Significantly Increases Survival Rates
Authors: Krammel Mario , Winnisch Markus , Hamp Thomas , Lobmeyr Elisabeth , Herkner Harald , Schreiber Wolfgang , Winnisch Dieter , Zajicek Andreas , van Tulder Raphael , Datler Philip , Keferboeck Markus , Poppe Michael , Zeiner Sebastian , Sulzgruber Patrick , Sterz Fritz
Published: July 2021

Background:
Sudden cardiac arrest (SCA) is one of the most common causes of death in western, industrialized countries. The hospital discharge rate after Out-of-Hospital Cardiac Arrests (OHCA with cardiac etiology and first monitored rhythm shockable) was 2011 24.7% in Vienna (Austria). The overall bystander CPR rate was 42% and in only 4% of the cases an AED was used by laypeople. Therefore, we wanted to assess whether a police first responder program with immediately initiated resuscitation measures (chest compression and use of an AED within the first three minutes) may increase survival rates after SCA in the Austrian capital.

Methods:
The police forces in Vienna were provided with 112 AEDs (52 in police cars / 60 at police stations) and CPR plus AED training. Emergency dispatching was organized such as AED-equipped police (P-AED) and conventional emergency medical service (EMS) responders were simultaneously dispatched to patients with assumed cardiac arrest. One month survival states of cardiac arrest victims provided with P-AED were compared to patient outcomes when EMS was the sole responder.

Results:
From August 2013 to April 2014, a 50% hospital discharge rate was observed for victims with initial ventricular fibrillation (VF) in the P-AED group, compared to 26% for standard EMS treatment. However, the overall survival benefit was diluted by the fact - that 75% of the initial rhythms were non-shockable, reducing the absolute survival to 10%. There have been 701 OHCA in this time, but due to lack of information, only 654 were included in the study. Figure 1 shows the outcome in detail.

Conclusion:
Use of AEDs by police first responders significantly increases survival and hospital discharge in VF patients. There was no benefit for victims with non-shockable rhythms yet. Further campaigning will be necessary, to increase the number of police first responder commitments and to implement an Austria wide P-AED system.
Abstract 324: Assessment in Therapeutic Hypothermia Protocol: A Quality Assessment Initiative and Analysis of Hemodynamic and Laboratory Parameters
Authors: Tasan Ediz , Bailey Alison , Campbell Charles
Published: July 2021

Background:
Therapeutic hypothermia (TH) is often considered for comatose patients with return of spontaneous circulation after cardiac arrest (CA). While patients undergoing out-of-hospital ventricular fibrillation cardiac arrest are thought to benefit most from TH, the individualized benefit of initiating TH is unknown. Using a combination of clinical and laboratory parameters at presentation, we sought a model to predict survival and discharge to home.

Methods:
We performed a retrospective study of patients undergoing TH after CA at the University of Kentucky Hospital from 4/1/11 to 12/31/13. Records confirmed by chart review. The primary outcomes were discharge disposition and death. We conducted logistic regression analyses to identify predictors of home discharge and survival.

Results:
The series included 80 patients (mean±SD age was 55.2±14.9, and 61% were male). The overall mortality rate was 67.9% with survivor home discharge disposition of 21.2%. The Apache II Score (estimated odds ratio [OR] 1.167) was a significant predictor of death; moreover, though not itself a significant predictor of death, troponin improved the ability of Apache II to predict death. The Apache II Score (OR 0.882) and Mean Arterial Pressure (OR 1.049) were significant predictors of home discharge. Figures 1 and 2 display estimated probabilities of survival and home discharge based on two-predictor logistic regression models.

Conclusions:
In patients undergoing TH, a favorable prognosis is anticipated given certain values for hemodynamic and laboratory parameters. Thus, the patient’s clinical presentation may provide additional guidance when considering initiation of TH after CA.
Abstract 340: Cardiac Autonomic Activity, Cardiac Function and Arrhythmogenic Property in Heart in Hemorrhagic Shock: Effect of Artificial Oxygen Carrier
Authors: Takase Bonpei , Tanaka Yoshihiro
Published: July 2021

Lethal ventricular arrhythmias (VT/VF) is serious complications in severe hemorrhagic shock (HS). Cardiac autonomic imbalance and dysfunction are well known unfavorable conditions. However, the effect of oxygenation including artificial oxygen carrier is not fully understood. To investigate the role of oxygenation in lethal HS, cardiac autonomic activity measures, cardiac function test, optical mapping analysis (OMP), and electrophysiological study (EPS) were performed in rats lethal HS.

Methods and Results:
1) Over the course of 150 min, rats were subjected to blood withdrawal (0.2 mL/min; total 85% bleeding) and simultaneously transfused with washed rat red blood cells (wRBC), liposome-encapsulated hemoglobin (LHb) or 5% albumin (5%ALB). Temporal changes in cardiac function by 2-D Echocardiography, heart-type fatty acid-binding protein (hFAB) levels, plasma levels of catecholamines, heart rate variability (HRV), and hypoxia-inducible factor 1α expression (HIF1) were measured. As results, > 85% of the rats transfused with either LHb or wRBC survived for 8 days. LHb transfusion suppressed HIF1 expression in the heart, maintained low levels of hFAB, and attenuated sympathetic nerve activity as reflected by changes in HRV and catecholamines. 2) After cannulating 22G catheter into the abdominal aorta, acute HS was induced by withdrawing 30% of total blood for 25 min. After HS, the rats were immediately resuscitated by transfusing the same amount of wRBC, LHb, or 5%ALB. After excising the heart, OMP and EPS were performed in Langendorff-perfused hearts. OMP revealed abnormal ventricular conduction delay in conjunction with impaired action potential duration (APD) dispersion in 5%ALB. In contrast, myocardial conduction velocity and APD dispersion were substantially attenuated in wRBC or LHb. Sustained VT/VF was easily provoked by burst pacing stimulus to the LV in 5%ALB whereas no VT/VF was induced with wRBC or LHb.

Conclusions:
The results indicate that wRBC and LHb attenuates cardiac dysfunction and sympathetic overactivity during lethal HS. Oxygenated hemoglobin transfusion by using either wRBC or LHb prevents VT/VF by preserving myocardial electrical structures caused by ischemia-reperfusion injury in HS.
Abstract 343: Prediction of Lifesaving Interventions Using Changes in Vital Signs from Prehospital Scene to Emergency Department
Authors: Mena Munoz Jorge H , Petersen Ashley , Guyette Francis X
Published: July 2021

Objective:
We investigate whether changes in vital signs between the prehospital scene and emergency department (ED) can be used to develop triage tools to predict the need for life-saving interventions (LSI) and survival in trauma patients.

Methods:
We analyzed a prospective cohort with any prehospital systolic blood pressure (SBP) ≤ 90 mmHg or Glasgow Coma Scale ≤ 8 who were admitted to an ED at 11 sites of the Resuscitation Outcomes Consortium. The primary outcome was the need for in-hospital LSI (e.g. invasive airway management, invasive bleeding control, blood transfusion, craniotomy, cardiopulmonary resuscitation). Secondary outcome was survival to hospital discharge. Changes in heart rate (HR), SBP, shock index (SI), and respiratory rate (RR) from first prehospital assessment to first ED assessment were considered as predictors in addition to sex, age, mechanism of injury, trauma center level, duration of transport, type of transport, and prehospital fluid volume. Decision trees for each outcome were developed using binary recursive partitioning with predictive performance measured using sensitivity, specificity, and classification error.

Results:
5625 subjects were included in our analysis with 49% in need of LSI and 21% dying prior to discharge. Patients needing an LSI tended to either: (1) have an increasing SI (delta ≥ 0.22), (2) have a decreasing SI (delta < 0.22) and >500 mL prehospital fluids, or (3) have a decreasing SI (delta < 0.22), ≤500 mL prehospital fluids, and large change in RR (delta ≥ 9.5 or delta < -7.5). Those surviving to discharge tended to either: (1) have a decreasing SI (delta < 0.57) and a HR that did not decrease greatly (delta > -47) or (2) have an increase in SI (0.57 ≤ delta < 1) and a declining RR (delta < 5). LSI tree had a sensitivity of 58.7% and specificity of 63.3%. Survival tree had sensitivity of 96.2% and specificity of 21.3%.

Conclusion:
Though the decision trees were constructed with the best data in terms of initial triage and early secondary triage, the classification performance was limited. This highlights the difficulties of developing vital sign based triage tools to predict the need for LSI and survival.
Abstract 46: Meta-analysis of Endotracheal Intubation Versus Supraglottic Airway Placement by Emergency Medical Services During Out-of-Hospital Cardiac Arrest
Authors: Benoit Justin L , Gerecht Ryan B , Steuerwald Michael T , McMullan Jason T
Published: July 2021

Objective:
Patients frequently undergo advanced airway management during out of hospital cardiac arrest (OHCA) resuscitation attempts. Recent observational data has associated endotracheal intubation (ETI) with worse outcomes and unacceptable failure rates. Supraglottic airways (SGA) are easier to insert, but the comparative effectiveness of this intervention is unclear. The objective of this study was to analyze all available data comparing patient outcomes for these two airway methods in OHCA patients treated by emergency medical services (EMS).

Methods:
A dual-reviewer search was conducted in PubMed, Embase, and the Cochrane Database with a research librarian to identify all relevant peer-reviewed articles. Exclusion criteria were traumatic arrests, pediatric patients, physician/nurse intubators, rapid sequence intubation, video devices, devices solely obstructing the esophagus, and studies using identical datasets. Outcomes were evaluated in two categories: (1) Early survival (return of spontaneous circulation or survival to hospital admission), and (2) Late survival (survival to discharge or neurologically intact survival). Results were summarized using odds ratios and combined using meta-analytic techniques, Cochran’s Q test, and the random effects model.

Results:
From 3,454 titles, we reviewed 325 abstracts, yielding 5 observational studies that fulfilled all criteria, with 60,635 ETI patients and 246,506 SGA patients. Important covariates such as age, gender, initial cardiac rhythm, witness status, and bystander CPR, were similar between patient groups in all studies. Significant study-level heterogeneity was present for both early survival (I2 = 87.3%, p < 0.001) and late survival (I2 = 66.1%, p = 0.001). Patients who received ETI had statistically significant higher odds of early survival (odds ratio 1.37, 95% confidence interval 1.04-1.81) but similar odds of late survival (odds ratio 1.17, 95% confidence interval 0.86-1.61) compared to SGA.

Conclusion:
Patients with OHCA treated by EMS are more likely to achieve return of spontaneous circulation or survive to admission after ETI compared to SGA, but this does not change ultimate survival. A randomized control trial is needed to further evaluate these associations.
Abstract 71: The Effect of Achieving Return of Spontaneous Circulation on Mitochondrial Respiration Following Prolonged Cardiac Arrest
Authors: Matsuura Timothy R , Bartos Jason A , Debaty Guillaume , McKnite Scott H , Rees Jennifer N , Riess Matthias L , Yannopoulos Demetris
Published: July 2021

Introduction:
Ischemia and reperfusion injury have been shown to alter mitochondrial function. Respiration, a primary function of mitochondria and marker of mitochondrial health, was previously believed to be unrecoverable after prolonged cardiac arrest. We investigated the effect that return of spontaneous circulation (ROSC) has on the mitochondrial respiratory profile of the myocardium.

Methods:
After 15 minutes of untreated ventricular fibrillation (VF), 16 pigs received mechanical CPR and intravenous epinephrine per standard AHA protocols. Defibrillation was first attempted after 4 minutes of CPR. In the event of persistent VF or pulseless electrical activity, CPR was continued for up to 15 minutes with epinephrine and defibrillations administered every 3 minutes. Animals that had ROSC were sacrificed 15 minutes after the initiation of resuscitation efforts. Another 6 animals were used as non-ischemic controls and had no cardiac arrest. Cardiac mitochondria were isolated. Respiration for complex I and complex II substrates was measured. Respiratory control index (RCI) was calculated as the ratio of state 3 to state 4 respiration. Mean RCI were compared via t-test and ANOVA. A p-value of < 0.05 was considered significant.

Results:
ROSC was achieved in 10 of 16 animals. Fifteen minutes after initiation of resuscitation efforts, animals that achieved ROSC had significantly higher complex I RCI compared to animals with ongoing CPR (8.0±0.8 vs. 4.3±0.4, p<0.01). Complex I RCI in animals that achieved ROSC recovered to that of non-ischemic controls (8.0±0.8 vs. 6.3±0.5, p=0.17). Complex II RCI did not differ between ROSC, CPR, and non-ischemic controls (3.2±0.3 vs. 2.7 ±0.2 vs. 3.2±0.1, respectively; p=0.40).

Conclusion:
Achieving ROSC after prolonged untreated cardiac arrest leads to normalization of mitochondrial respiration within 15 minutes of the initiation of resuscitation efforts. At the same time, complex I RCI is suppressed and complex II RCI is unaffected during ongoing CPR. Decreased mitochondrial complex I respiration during ongoing CPR could be the cause or the effect of the absence of ROSC. Further investigation is needed.
Abstract 80: Development of CA1 Damage: Different Cell Counts in CA1 Region of Rats Resuscitated from 8-Minute Ventricular Fibrillation Cardiac Arrest After 2 Weeks of Survival Compared with 20 Weeks of Survival
Authors: Weihs Wolfgang , Sterz Fritz , Ettl Florian , Magnet Ingrid A M , Warenits Alexandra-Maria , Schober Andreas , Testori Christoph , Teubenbacher Ursula , Grassman Daniel , Wagner Michael , Holzer Michael , Janata Andreas , Högler Sandra
Published: July 2021

Background:
Rodent models of cardiac arrest (CA) help to investigate mechanisms and therapy of cerebral ischemia and reperfusion. The CA1 region of hippocampus is specifically vulnerable to global ischemia and is considered to play an important role in neurological deficits of patients surviving cardiac arrests.

Methods:
Male 350g Sprague-Dawley rats were put into ventricular fibrillation (VF) CA. After 8 min of CA the animals 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. Six animals surviving with favorable neurologic recovery were sacrificed after 2 weeks and 11 after 20 and compared to 4 sham rats. For histological examination brains were fixed in formalin, paraffin-embedded and cut into coronary sections of 3 μm thickness. In Hematoxylin- Eosin-stained sections viable neurons were counted in a 500 μm sector of the CA1 region.

Results:
In sham animals 84±12 viable cells were counted in CA1 region. Two week survivors had 16±8 cells (p< 0.001), whereas 20 week survivors had 37±31 (p=0.018 vs sham, p=0.084 vs 2 weeks survivors) cells. The latter showed in 7 animals many viable cells (60±15) compared to 2 weeks survivors and in 4 animals very few cells 4±3 cells.

Conclusions:
A repopulation within week 2 and 20 of pyramid cells in the CA1 region of the hippocampus seems to have taken place in 7 of 11 rats resuscitated from 8 min VFCA whereas in others not. To discover the mechanism responsible for this huge difference in cell counts of the CA1 region in long time survivors of CA might help to understand the pathological mechanisms of the global ischemic insult.
Abstract 81: Early Access to Cardiac Catheterization Laboratory for Patients Resuscitated from Cardiac Arrest Due to a Shockable Rhythm: The Minnesota Resuscitation Consortium Twin Cities Unified Protocol Two-Year Report
Authors: Yannopoulos Demetris , Garcia Santiago , Mahoney Brian , Frascone Ralph J , Helmer Greg , Lick Charles , Conterato Marc , Baran Kenneth W , Bart Bradley , Roh Steven , Panetta Carmelo , Stark Randall , Haughland Mark , Mooney Michael ,   Minnesota Resuscitation Consortium
Published: July 2021

Background:
Cardiac arrest patients that have been successfully resuscitated from shockable rhythms have a high prevalence of thrombotic and/or flow limiting coronary occlusion regardless of the presence of STEMI on the ECG. In 2012, the Minnesota Resuscitation Consortium (MRC) developed an organized approach for all those patients to gain early access to the cardiac catheterization laboratory (CCL). We report the two-year outcomes.

Methods:
Eleven metropolitan hospitals with 24/7 PCI capabilities agreed to provide early (within 2 hours of arrival to the emergency department) access to the CCL for all patients that were successfully resuscitated from VF/VT arrest regardless of the presence or absence of STEMI on the surface ECG. Inclusion criteria were: witnessed or un-witnessed, age >18 and <70, cardiac arrest of presumed cardiac etiology, comatose or conscious patients. Patients with PEA or asystole, known DNR/DNI, non-cardiac etiology, significant bleeding of any cause, terminal disease were excluded. Patient outcomes were recorded in the state database Cardiac Arrest Registry to Enhance Survival.

Results:
A total of 370 patients were resuscitated and met the inclusion criteria. Of those, 313 (85%) patients were taken to the CCL per protocol. The mean age was 55.5 years, 77% were men and 79% had witnessed arrest. Only 57 patients (15%) did not gain access to the CCL. Of the 313 patients that had early coronary angiography a total of 47% received primary angioplasty and had at least one vessel disease and 5% received coronary artery bypass. All comatose patients received therapeutic hypothermia and 35% received and implantable cardiac defibrillator. A total of 235/313 (75%) were discharged alive and of those 222/235 (94.5%) were discharged neurologically intact with a CPC of 1. Of the patients that did not gain access to the CCL, 46% (26/57) were discharged alive and of those 73% (19/26) had CPC of 1 [OR: 3.63; 2.03-6.5, p< 0.001].

Conclusions:
Over the first two years of implementation, the MRC protocol for early access to the CCL in resuscitated patients from shockable rhythm was associated with 75% survival to hospital discharge and excellent neurological outcomes in a large metropolitan area and real-life clinical practice.
Abstract 9381: Comparison of Clinical Characteristics and Adverse Outcomes in Pregnant Women with Cardiomyopathy Subtypes at the Time of Delivery in the US: 2006-2010
Authors: Lima Fabio V , Parikh Puja B , Zhu Jiawen , Yang Jie , Stergiopoulos Kathleen
Published: July 2021

Introduction:
Investigation of patient characteristics and outcomes in women with cardiomyopathy (CDM) at the time of delivery has been limited. The aim of this study was to determine the clinical characteristics and outcomes in women with peripartum (PCDM) and hypertrophic cardiomyopathy (HCDM), and the predictors for adverse clinical outcomes in pregnant women at the time of delivery.

Methods and Results:
The Healthcare Cost and Utilization Project’s National Inpatient Sample was screened for hospital admissions for delivery in pregnant women with CDM subtypes (peripartum, hypertrophic and all others) from 2006-2010. Clinical characteristics and maternal outcomes were identified in women with subtypes of CDM and without. The primary outcome of interest was major adverse clinical events (MACE), a composite of in-hospital death, acute myocardial infarction, heart failure, arrhythmia, cerebrovascular event, or embolic event. Our study population consisted of 2,078 patients with CDM and 4,438,439 patients without CDM. Of those with CDM, 52 (2.5%) had HCDM, 1039 (50.0%) had PCDM, and 987 (47.5%) were classified as other CDM (OCDM). PCDM cohort was more likely to be insured by Medicaid and the HCDM patients were more likely to deliver at a teaching hospital (p<0.01 for all). The PCDM and all OCDM cohorts had a larger proportion of black patients and most were from the South. PCDM patients experienced the highest rates of MACE (46%), compared with HCDM (23%) or OCDM (38.9%), mainly driven by heart failure and arrhythmia. Maternal mortality in all CDM subgroups was extremely low (< 0.5%). Significant predictors of MACE in the PCDM cohort were the presence of valvular heart disease (OR 2.16, 95% CI 1.49-3.14), severe pre-eclampsia (OR 1.54, 95% CI: 1.08-2.21), and Cesarean delivery (OR 1.36, 95% CI: 1.04-1.78); delivery at a teaching hospital was associated with a reduction in MACE. In multivariable analysis, the presence of PCDM (OR 2.22, 95% CI 1.07-4.55) was independently predictive of MACE.

Conclusions:
Peripartum CDM patients had the highest likelihood of MACE compared to hypertrophic and all other CDM subtypes.
Abstract 9401: Medicare Readmission Penalties and Their Socioeconomic Correlates in Urban Hospitals
Authors: Williams Kim A , Hamid Muhammad S , Javed Arshad A , Horton Amy M
Published: July 2021

In 2013, 2,200 U.S. hospitals forfeited more than $280 million in Medicare funds due to readmission penalties (RPs) for heart failure, pneumonia and myocardial infarction stipulated by the Affordable Care Act. This study evaluated the RPs in the hospitals of large cities, in comparison with other areas within and between states.

Methods:
Medicare RPs for 2013 (ranging 0 to 1%) were compared along with census and socioeconomic data for the largest city in each of 49 states in the United States, excluding Maryland due to its ongoing Medicare demonstration project. Improvements in RPs for 2014 in each urban area were tabulated.

Results:
There was a significant correlation between RPs and the size of the population of the cities (r = 0.37, p<0.01), with larger cities receiving higher penalties. For example, Detroit, MI’s 5 hospitals and Newark, NJ’s 3 hospitals have the highest average RPs (0.9%) than the hospitals in other largest cities. The RPs correlated moderately with a higher percentage of low-educated people in the city (r=0.53, p<0.001), and weakly but negatively with the percentage of high-educated people (r= -0.29, p<0.05) in the city. The rate of unemployment also correlated positively and significantly with the RPs (r=0.50, p<0.001).

Conclusion:
RPs reduce Medicare payments to inner-city hospitals, such as those in Detroit, MI and Newark, NJ, and disproportionately lower payments to large cities with poorer, underemployed and undereducated populations. This may have the unintended consequence of further reducing access care from safety-net hospitals.
Abstract 9600: Abnormal Lipoprotein Metabolism Other Than LDL Fraction in Familial Hypercholesterolemia: Serial analysis using Ultracentrifugation Method
Authors: Tada Hayato , Kawashiri Masa-aki , Hodatsu Akihiko , Nakanishi Chiaki , Konno Tetsuo , Sakata Kenji , Yoshimuta Tsuyoshi , Hayashi Kenshi , Nohara Atsushi , Inazu Akihiro , Mabuchi Hiroshi , Yamagishi Masakazu
Published: July 2021

Background:
It is well known that familial hypercholesterolemia (FH) is a common inherited disorder that could cause marked elevation of plasma LDL-C level. However, few data exists regarding the clinical impact of plasma levels of VLDL-C and IDL-C as well as the composition of each lipoprotein fraction in FH. Thus, we assessed the hypothesis that the abnormality in LDLR modulates the quality as well as the quantity of lipoprotein other than LDL fraction.

Methods:
We investigated the plasma lipoprotein by ultracentrifugation method about 146 controls (mean age=61.4±17.1yr, mean LDL-C=92.7±61.2mg/dl), 213 heterozygous mutation-determined FH subjects (mean age=46.0±18.0yr, mean LDL-C=225.1±61.2mg/dl), and 16 homozygous mutation-determined FH subjects (mean age=26.9±17.1yr, mean LDL-C=428.6±86.1mg/dl). In addition, we evaluated the composition of each lipoprotein fraction by calculated cholesterol ester (CE) / triglyceride (TG) ratio.

Results:
As shown in the figure, the differences of the levels of TC and LDL-C between these 3 groups as well as those of VLDL-C (19.5±10.4, 25.2±19.3, 29.5±21.4 mg/dl, respectively) and IDL-C (8.3±3.7, 16.8±11.5, 40.0±37.3 mg/dl, respectively) were statistically significant. Moreover, the ratios of CE/TG of each lipoprotein fraction significantly increased in heterozygous FH and homozygous FH group, compared with that of controls, suggesting that the abnormality in LDLR modulate the quality as well as the quantity of each lipoprotein fraction.

Conclusions:
Our results indicate that LDLR participate not only in metabolism of LDL fraction but also in that of VLDL and IDL fractions. Larger amounts of VLDL-C and IDL-C with worse quality should also be additive risk factor in FH subjects.
Abstract 9601: Early Coronary Atherosclerotic Morphology in Pseudoxanthoma Elasticum: Images From Intravascular Ultrasound and Optical Coherence Tomography
Authors: Tada Hayato , Kawashiri Masa-aki , Hodatsu Akihiko , Nakanishi Chiaki , Konno Tetsuo , Sakata Kenji , Yoshimuta Tsuyoshi , Hayashi Kenshi , Nohara Atsushi , Inazu Akihiro , Mabuchi Hiroshi , Yamagishi Masakazu
Published: July 2021

Background:
Pseudoxanthoma elasticum (PXE) is an inherited systemic disease of connective tissue primarily affecting the skin, retina, and cardiovascular system. It is characterized pathologically by fragmentation and calcification of elastic fiber. However, few data exist regarding the pathogenesis of the coronary atherosclerosis due to the rarity of this disease. The aim of the present study was to assess the early atherosclerotic morphology in PXE using intravascular ultrasound (IVUS) and optical coherence tomography (OCT).

Methods:
We assessed detailed morphological changes of the coronary arterial wall by IVUS and OCT of the two PXE cases (73 yr male and 69 yr female), both of whom were without any evidence of coronary risk factor. Distal portion of the left anterior descending artery, that was not evident of plaques by angiography, was evaluated using commercially available IVUS system and OCT system.

Results:
Using IVUS modality, an additional high-gain layer without acoustic shadow, which was located in the intima-media complex, was detected. This additional layer represented several tissue characteristics including fibrosis, dense fibrosis, and calcification using integrated backscatter-IVUS. The OCT image revealed this abnormal layer as heterogeneous shaggy intima without thickness, suggesting the presence of calcified fragmented internal elastic lamina.

Conclusions:
We report the first IVUS and OCT findings in the coronary artery in patients with PXE. These images suggest that the unique morphology found in those subjects represent a preclinical, early stage of coronary atherosclerosis in PXE.
Abstract 9634: As Compared With Cardiac Magnetic Resonance Imaging, Transthoracic Echocardiography Has an Excellent Accuracy in Diagnosing a Left Ventricular Thrombus After an Anterior Myocardial Infarction Complicated With Left Ventricular Dysfunction: Results of a Prospective Multicentric Study
Authors: Meurin Philippe , Brandao Carreira Virginie , Dumaine Raphaelle D , Shqueir Alain , Milleron Olivier , Safar Benjamin , Perna Sergio , Smadja Charles , Genest Marc , Garot Jerome , Carette Bernard , Payot Laurent , Tabet Jean Yves
Published: July 2021

Introduction:
The generalization of reperfusion techniques to treat acute myocardial infarction (MI) has allowed for markedly reduced incidence in left ventricular (LV) thrombi because of the reduced myocardial damage. LV thrombi are estimated to complicate 5% to 10% of unselected anterior-wall MI (Ant-MI). However, the incidence and evolution of LV thrombi in high-risk patients with Ant-MI complicated by LV systolic dysfunction is not well known. Cardiac magnetic resonance imaging with contrast delayed enhancement (CMR-DE) is the gold standard in assessing LV thrombus, but comparisons of transthoracic echocardiography (TTE) and CMR-DE are scarce.

Hypothesis:
We assessed whether LV thrombi are still frequent after major Ant-MI, despite systematic dual antiplatelet therapy, and whether focused TTE has a good accuracy for detection as compared with CMR-DE.

Methods:
From 2011 to 2013, from 7 centers, we prospectively included patients with LV ejection fraction (LVEF) < 45% at a first TTE performed < 7 days after Ant-MI. A second evaluation including TTE and CMR-DE (analyzed by blinded examiners) was performed at 30 days. A third TTE and assessment of clinical status and adverse events were performed between months 6 and 12.

Results:
We included 100 consecutive patients (71% males; mean age 59.1 ± 12.1 years; LVEF 33.5 ± 6.0%) at a mean of 4.8 ± 1.9 days after Ant-MI; 88% had undergone primary coronary angioplasty. In total, 26 patients had LV thrombi detected at a mean of 23.2 ± 34.8 days after MI (6 during the first week after the MI, 16 from days 8 to 30, 4 after day 30). As compared with CMR-DE, TTE sensitivity and specificity were 94.7% and 98.5%, respectively. For 24 patients (92.3%), the LV thrombi disappeared with triple antithrombotic therapy including dual antiplatelet therapy and a vitamin K antagonist. One patient died from a recurrent subdural haematoma and another had a peripheral embolism.

Conclusions:
In this prospective multicenter study, LV thrombus occurred in 26% of patients after Ant-MI complicated by LV dysfunction. Focused TTE has a high accuracy for detection. CMR-DE should be performed only when the apex is not clearly seen.