bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 19260: Prothrombotic Activity and Reduction in Coronary Flow Reserve Associated With Therapeutic Intracoronary Delivery of Bone Marrow-Derived Mesenchymal Stem Cells is Ameliorated by Heparin Co-Administration in a Porcine Myocardial Infarction Model
Authors: Gleeson Birgitta M , Martin Kenneth , Kumar Arun H , Ali Mohammed T , Barry Frank P , O’Brien Timothy , Caplice Noel M
Published: April 2024

Cell therapy remains an evolving therapeutic option for cardiac repair in the case of acute myocardial infarction (AMI) associated with significant cardiomyocyte death. Mesenchymal stem cells (MSCs) are promising candidates for promoting myocardial salvage post AMI, but concerns regarding the safety of intracoronary MSC delivery remain. Surface expression of tissue factor (TF), a key initiator of the soluble coagulation cascade, has recently been implicated as a possible cause of MSC procoagulant activity. This study aimed to characterize the prothrombotic activity of MSC and identify means of managing any thrombotic side effects during therapeutic intracoronary delivery post AMI. Expression of TF on MSC was detected by immunoflourescence, flow cytometry and immunoblotting. TF antigen was catalytically active (252.4 ± 8.3 pM/2 x 105 MSC) and capable of supporting thrombin generation in vitro. Addition of MSCs to whole citrated blood enhanced platelet-driven thrombus deposition on collagen at arterial shear flow (12.67 ± 1.0% untreated vs 18.9 ± 0.9% surface coverage with MSC, p>0.001), an effect abolished by heparin co-administration (p<0.01 vs MSC alone). Infusion of 25 x 106 MSC via an intracoronary route in a porcine AMI model was associated with a decrease in coronary flow reserve when delivered during reperfusion (-0.7 ± 0.05) but not when coadministered with heparin (0.1 ± 0.02, p<0.01). Heparin also reduced MSC-associated thrombosis incorporating platelets and vWF in the microvasculature (p<0.05). Therapeutic MSC delivery was able to reduce apoptosis in the infarct border zone 24 post AMI (p<0.01). Procoagulant activity associated with therapeutic MSCs is independently associated with reduction in myocardial perfusion when delivered I.C. which may be successfully managed with heparin co-administration. This study highlights an important mechanistic insight into safety concerns associated with therapeutic intracoronary MSC delivery for AMI.
Abstract 2: PTEN Inhibition Improves Cardiovascular Function and Energy Metabolism While Decreasing Inflammation After Mouse Cardiac Arrest
Authors: Li Jing , Wang Huashan , Shao Zuohui , Zhu Xiangdong , Chen Sy-Jou , Li Changqing , Steinhorn Benjamin , Zhong Qiang , Costakis James , Bunney Gabrielle , Beiser David , Vanden Hoek Terry L
Published: April 2024

Introduction:
The survival kinase Akt mediates therapeutic hypothermia protection after mouse cardiac arrest (CA). This central kinase affects cardiovascular function, metabolism and inflammation. Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is a primary phosphatase that negatively regulates Akt activity. We hypothesized that the PTEN inhibitor, VO-OHpic (VO), will mimic hypothermia protection by enhancing energy metabolism and cardiac function while reducing inflammation after CA.

Methods:
C57BL6 mice underwent 8 min of KCl-induced (0.08 mg/g) asystolic CA. VO (10 μg/kg) was administrated IP 30 min before CA. Neurologically intact survival at 72 h after CPR was measured and cardiac function was evaluated by Millar catheter. Blood lactate and glucose were assessed using colorimetric kits, and a cytokine panel using multiplex ELISA. Phosphorylation of Akt, GSK3β and phospholamban in heart and brain were studied by Western blot as markers of Akt activation. Heart cells isolated from 1-2-day old C57BL6 mice and exposed to 30 min ischemia and 90 min reperfusion were used to measure VO effects on contractile function in a cell model of cardiac stunning.

Results:
VO improved 72 hour survival (90% vs. 50%, p < 0.01). At 30 min after ROSC, VO significantly increased Dp/dt max (5123.4 ± 1026.9 mmHg/s vs. 4033.5 ± 622.4 mmHg/s, p<0.05), and ETCO2 (39.1 ± 2.8 vs. 35.3 ± 1.2 mmHg, p<0.05) with continued benefit seen at 2 hours. VO significantly increased lactate clearance by 4 hours demonstrated by decreased plasma lactate and glucose. The anti-inflammatory cytokine IL10 was increased while VO decreased the pro-inflammatory IL-1β. VO increased the phosphorylation of Akt (Thr308 and Ser473), p-GSK3β and the Akt target phospholamban. In mouse cardiomyocytes, VO (1 μM) improved the contractile velocity (54.6 ± 2.3 % vs. 33.3 ± 3.9 %, p < 0.05), increased total ATP content and the ratio of ATP/ADP during ischemia and enhanced L-type calcium channel recovery.

Conclusions:
PTEN inhibition improved neurologically intact survival after CA, with improved energy metabolism and cardiac function, and decreased inflammation. Use of PTEN inhibitors such as VO may be a novel strategy with or without cooling for treating the metabolic phase of cardiac arrest.
Abstract 225: Healthcare Provider Perspectives on Resuscitation of Drug-Related Out-of-Hospital Cardiac Arrest
Authors: Koller Allison , Salcido David D , Callaway Clifton W , Menegazzi James J
Published: April 2024

Introduction:
Out-of-hospital cardiac arrest from drug overdose (OD-OHCA) caused over 38,000 deaths in 2010. A preliminary study in Pittsburgh found that OD-OHCA patients differed demographically and in the resuscitation treatments they received, despite identical American Heart Association (AHA) resuscitation guidelines. We hypothesized that physician and non-physician healthcare provider perceptions affect decision-making in the treatment of OD-OHCA versus non-OD OHCA.

Methods:
A handwritten survey was administered at the National Association of EMS Physicians 2013 Scientific Assembly between January 9 and 12, 2013. Participants were asked about their affiliated EMS agencies, perceptions of OD-OHCA incidence and abused drugs, and perspectives on and knowledge of the treatment of OD-OHCA during resuscitation. Participants were instructed to complete only one survey.

Results:
In sum, 193 respondents participated in this survey: 144 (75%) were physicians and 49 (25%) were non-physician healthcare providers. Of the physicians, 79% identified current status as a medical director and 76% of non-physicians identified as a paramedic. Eighty-three percent of physicians and 65% of non-physicians indicated that OD-OHCA patients had different demographics than non-OD OHCA; 64% all respondents felt that OD-OHCA patients should be treated differently. Of those respondents who believed that OD-OHCA patients should be treated differently, 47% believed there were differences in the AHA guidelines, while only 27% of those respondents who believed that OD-OHCA patients should not be treated differently believed that AHA guidelines recommended differential treatment. Fifty-four percent of all respondents reported that they or their paramedics make different decisions when treating OD-OHCA patients, regardless of protocol. Seventy-eight percent of respondents indicated the use of naloxone during OD-OHCA resuscitation while 12% reported administering naloxone during non-OD OHCA resuscitations.

Conclusions:
Physicians and non-physicians report perceiving OD-OHCA patients differently than non-OD and making different treatment decisions based on these perceptions. This may result in etiology-oriented resuscitation for OD-OHCA.
Abstract 232: Temperature Profile of Esophageal, Rectal and Tympanic Temperature Probes in a Rodent Model of Cardiopulmonary Bypass Resuscitation from Ventricular Fibrillation Cardiac Arrest
Authors: Magnet Ingrid A , Ettl Florian , Weihs Wolfgang , Warenits Alexandra , Grassmann Daniel , Wagner Michael , Teubenbacher Ursula , Sipötz Johann , Sterz Fritz , Janata Andreas
Published: April 2024

BACKGROUND:
Exact and valid temperature measurement is crucial to assess the effects of temperature levels on outcome after cardiac arrest (CA). In this study, we assessed the temperature profile in different body locations in our rat ventricular fibrillation (VF) CA model with emergency cardiopulmonary bypass (ECPB) resuscitation.

METHODS:
Adult Sprague-Dawley rats (400g) were equipped with esophagus (Tes), tympanic (Ttym) and rectal (Trec) temperature probes along standard instrumentation. Following 10 min of VF CA, rats were randomized to normothermic control (NT, 37±0.5°C), mild hypothermic (MH, 33±0.5°C) or deep hypothermic (DH, 27±0.5°C) reperfusion and put on ECPB for 15 min. On ECPB rats were rapidly cooled to and maintained at target temperature. After ECPB and return of spontaneous circulation (ROSC), MH and DH were maintained mild hypothermic with surface cooling/warming. Temperature profiles for the first five rats in the DH group are presented as mean±SD, variances tested by ANOVA and post-hoc Tukey analysis.

Results:
Before CA, all rats were normothermic with all three probes and cooled passively by 0.8±0.6°C during CA. In the MH and NT group, no differences in temperature measurements were found during the entire experiment, whereas in the DH group, temperature profile of the three probes significantly differed, which is presented below. With start of ECPB, cooling rate was significantly higher according to Tes (2.5±0.7°C/min) versus Ttym (1.4±0.6, p=0.44) or Trec (0.6±0.2, p=0.002) and target temperature reached by Tes within 2.8±1.0 min, but only in two animals by Ttym (4.5±0.7 min) and not at all by Trec. Rewarming rate to mild hypothermia at the end of ECPB did not vary significantly between probes (0.12±0.02) and was reached by 33±4 min.

CONCLUSION:
Even in a small animal model, temperature differs significantly in measurement locations. But what is true brain temperature? In future studies, measurement of brain temperature might be indicated.
Abstract 237: Do We Treat Women Differently? Health Care Providers’ Perspectives on Gender Differences in Post-arrest Care
Authors: Parsons Janet , Rac Valeria E , Baker Natalie A , Racz Elizabeth , Gaudio Michelle , Dorian Paul , Fowler Robert , Slutsky Arthur , Dainty Katie , Scales Damon , Bierman Arlene S , Abramson Beth L , Cheskes Sheldon , Gray Sara , Kiss Alex , Morrison Laurie J
Published: April 2024

Objective:
To explore the perspectives of health care providers (HCP) on previously observed gender-related differences in post-arrest care, and to identify potential barriers to care delivery amenable to modification that may minimize disparities in care.

Methods:
Qualitative study based on semi-structured interviews conducted with 27 HCPs at six hospitals in southern Ontario from July 2012 through March of 2013. A combination of purposeful and snowball sampling was used to recruit representative participants: gender, age, professional designation, and practice settings). Interviews were conducted by phone or in-person and lasted from 15-60 minutes. All interviews were audio-taped, transcribed, and coded inductively using a descriptive content analytic approach to identify common themes and patterns (constant comparison).

Results:
Most HCPs indicated that they did not feel that the care offered to female and male post-arrest patients was markedly different; rather each patient is treated as “a life to be saved” where treatment is by protocol and each arrest is context-dependent. In attempting to address potential differences in care, participants characterized gender as one of many contributing factors (clinical, social and individual circumstances), that are entangled with other social determinants of health (age, family structure, ethnicity). Factors operating at the individual-, institutional- and social structural levels may explain any observed differences. For example, once patients are transferred to the ICU for ongoing management, many HCPs felt that decision-making surrounding withdrawal of life support might differ based on gender, but intersects closely with other factors including family support, ethnicity and religion.

Conclusion:
HCPs do not perceive gender-based differential access to evidence-based resuscitation care is occurring. They do not believe differential access is contributing to observed differences in post-arrest outcomes between men and women. Rather, gender was portrayed as embedded within an array of social determinants of health as well as clinical and physiological factors that were difficult to separate. Future studies should focus on these other factors and explore how they relate to gender.
Abstract 245: Secular trends of Cardiovascular Comorbidities and Associated Mortality among Patients With In-hospital Cardiac Arrest: a 20-year Experience From Qatar (1991-2010)
Authors: Salam Amar M , AlBinali Hajar , Singh Rajvir , Al-Qahtani Awad , Al Suwaidi Jassim
Published: April 2024

Objectives:
Little is known about the trends of in-hospital cardiac arrest (IHCA) mortality and associated cardiovascular comorbidities in the developing countries. This was examined in this study of a 20-year prospectively collected registry of all patients hospitalized with acute cardiac events in a Middle-Eastern Country.

Methods:
Retrospective analysis of all patients that developed IHCA in Qatar from 1991 through 2010 was made. Rates and trends of cardiac comorbidities and in-hospital mortality were examined.

Results:
During the 20-years period 41,436 patients were hospitalized with acute cardiac disease in Qatar From 1991 to end of 2010. Of these 1684 patients (4.06%) developed IHCA. In the latter years of the study there was a significant increase in the prevalence of diabetes mellitus and hypertension when compared to patients hospitalized in the earlier years. Associated ischemic heart disease and heart failure were also significantly trending higher. The study demonstrated an increasing rate of in-hospital mortality of patients with IHCA over the 20-year period that peaked in the period (1999-2002).

Conclusions:
Our study demonstrated that the poor survival after IHCA was associated with an increase in the prevalence of cardiovascular comorbidities in our patients. Tailored strategies for the prevention and treatment of these conditions are warranted to reduce the burden of cardiovascular disease and its related mortality in our region.
Abstract 250: The Association of Advanced Age and Outcomes in Targeted Temperature Management After Out-of-hospital Cardiac Arrest
Authors: Seethala Raghu R , Yamane David P , Avery Kathleen R , O’Brien Molly H , Kyller Michael G , Griswold Karen M , Pierce Carol D , Szumita Paul , Stone Peter H , Massaro Anthony F , Henderson Galen V , Morrow David A , Scirica Benjamin M
Published: April 2024

Background:
Therapeutic hypothermia or targeted temperature management (TTM) is the only therapy shown to improve neurologically intact survival post cardiac arrest. One of the original randomized control trials evaluating TTM, excluded patients older than 75. Advanced age has been associated with poor outcomes following cardiac arrest. However, investigations have shown that elderly patients that actually survive cardiac arrest may go on to have good outcomes. Given these findings it is unclear whether TTM benefits elderly patients.

Objectives:
We hypothesized that in patients undergoing TTM, advanced age would be associated with decreased survival to discharge as well as decreased neurologically intact survival.

Methods:
We performed a retrospective single center study of 140 patients who underwent TTM after cardiac arrest over a four-year period. Patients were analyzed based on advanced age defined as age greater than or equal to 80. The primary outcomes were survival to discharge and neurologically intact survival defined as a CPC score of 1 or 2. We compared baseline characteristics including: initial lactate, witnessed arrest, down time, initial cardiac rhythm, bystander CPR and vasopressor use.

Results:
A total of 140 patients underwent TTM (12 patients with advanced age vs. 128). Fewer patients survived in the advanced age group (8.3% vs. 43% p =0.01), and fewer survived with good neurologic function (8.3% vs. 35.9% p = 0.03). Baseline characteristics were similar except for a lower proportion of VF/VT in the advanced age group (16.7% vs. 52.8% p=0.01). After adjusting for these characteristics, advanced age was still associated with decreased survival (p = 0.04), but not with decreased neurologically intact survival (p =0.15). When age greater than or equal to 75 years was chosen as the cut off for advanced age, survival to discharge was 17.4 % (4/23) with all survivors having good neurologic function.

Conclusions:
Age greater than 80 was associated with decreased survival to discharge but not with decreased neurologically intact survival. Additionally, all of the survivors 75 or older had good neurologic outcomes. Further study is needed to establish the benefits of TTM in the elderly.
Abstract 254: Should All Patients without Sustained Return of Spontaneous Circulation Following Ventricular Fibrillation Out-of Hospital Cardiac Arrest be Transported to Hospital?
Authors: Stub Dion , Nehme Ziad , Bernard Stephen , Lijovic Marijana , Kaye David M , Smith Karen
Published: April 2024

Background:
Many worldwide emergency medical services, including Ambulance Victoria, do not routinely transport patients without sustained return of spontaneous circulation (ROSC) following out-of-hospital cardiac arrests (OHCA), given the logistical difficulties and historical poor outcomes. The significant recent advancements in resuscitation techniques for prolonged cardiac arrest including mechanical chest compression and extracorporeal membrane oxygenation assisted CPR makes the decision of when and where to cease resuscitative efforts increasingly difficult. We aimed to explore the characteristics and outcomes of patients with OHCA who do not achieve sustained ROSC using the Victorian Ambulance Cardiac Arrest Registry (VACAR).

Methods and Results:
The VACAR was searched for adult non-EMS witnessed OHCAs with an initial shockable rhythm between 2003 and 2012. There were 5654 OHCA meeting inclusion criteria. Analysis was performed on 3095 (54%) of patients who did not achieve sustained ROSC in the field. Of these patients only 589 (20%) had ongoing CPR to hospital with the remainder declared deceased. Patients transported with ongoing CPR were younger (median 63 vs 68 years, p<0.01), had shorter response times and time to first defibrillation, but longer resuscitation times (median 42 vs 33 minutes, p <0.01). Survival to hospital discharge occurred in 52 (9%) of patients with ongoing CPR during transportation to hospital. 97% of these patients were discharged with a favourable neurological outcome. Independent predictors of a patient being transported to hospital with ongoing CPR included younger patients, who arrested in public places, and received longer resuscitation times.

Conclusion:
Patients receiving ongoing CPR during transport to hospital have better outcomes than previously reported. Declaring patients deceased in the field in the setting of an initial shockable rhythm, in which ROSC cannot be achieved may no longer be warranted. The further development of systems of care that incorporate transport of patients requiring ongoing CPR is urgently needed.
Abstract 282: Poloxamer 188 Improves Intra-CPR Hemodynamics and Post-Resuscitation LV Function in a Pig Model of Prolonged Cardiac Arrest
Authors: Matsuura Timothy , Bartos Jason , Sarraf Mahammad , Houang Evelyne , McKnite Scott , Rees Jennifer , Sloper Daniel , Caldwell Emily , Bates Frank , Metzger Joseph , Yannopoulos Demetris
Published: April 2024

Introduction:
Poloxamer 188 (P188) is a copolymer surfactant that has been shown to protect against ischemia/reperfusion injury. We hypothesized that P188 administration at the initiation of cardiopulmonary resuscitation (CPR) would improve post-resuscitation LV function.

Methods:
Following 15 min of untreated ventricular fibrillation (VF), 12 pigs received 4 minutes of CPR with automated active compression/decompression and an impedance threshold device. Six animals received an IV bolus (250 mg/kg) at the initiation of CPR and infusion of 120 ml of 150 mg/ml of P188 for 4 hours after return of spontaneous circulation (ROSC). Six other animals received no P188 (CTL). Aortic systolic (AoS), diastolic (AoD), and right atrial diastolic (RAD) pressures were recorded continuously. Coronary perfusion pressure (CPP) was calculated as the difference between AoD and RAD. All animals received 0.5 mg of epinephrine 1 min prior to defibrillation. Left ventricular ejection fraction (LVEF) was obtained with echocardiography 1 and 4 hours after return of spontaneous circulation (ROSC). Unpaired t-tests were used for statistical analysis; significance assumed at p<0.05 (two-tailed).

Results:
5/6 animals treated with P188 and 6/6 CTL animals had ROSC. P188 significantly increased intra-CPR hemodynamics (table) and eliminated post resuscitation LV ventricular dysfunction. LVEF at 1 and 4 hours post ROSC with P188 vs. CTL was 58±7 and 62±11% versus 36±12 and 38±9 %, respectively (p<0.05).

Conclusion:
Poloxamer 188, when administered at the initiation of CPR as a bolus and as an infusion post ROSC, improved intra-CPR hemodynamics and post-ROSC LVEF after 15 minutes of untreated VF in an animal model. The mechanism of action is thought to be membrane stabilization and this will be the aim of future studies.
Abstract 311: Defibrillation in Public Places. Who is Shocking the Patients?
Authors: Ringh Mattias , Hollenberg Jacob , Rosenqvist Mårten , Jonsson Martin , Nordberg Per , Fredman David , Svensson Leif
Published: April 2024

Background:
In 2003, survival from Out of Hospital Cardiac Arrest (OHCA) was 2,5 % in Stockholm county. To increase survival, a first responder system was implemented in 2005 in parallel with a structured Public Access Defibrillation (PAD) program. In addition, the number of “wild” public Automated External Defibrillators (AEDs) has rapidly increased over time.

Aim:
To evaluate the impact on survival from three different defibrillation strategies (EMS, first responders and PAD) in OHCA patients available for PAD in Stockholm County, Sweden.

Methods:
All witnessed cases of OHCA outside home of cardiac origin with shockable rhythm in Stockholm County 2006-2012 were considered subjects for PAD and were included in the study. 60 high incidence sites were initially selected for the PAD program, and security officers and lay responders were trained to respond to “on site” emergencies. The number of sites in the PAD program increased to 120 at the end of the study. 35 fire stations throughout the county were available for simultaneously dispatch to suspected OHCAs. By approximations based on wholesale numbers, around 1000 public AEDs were present outside the PAD program.

Results:
469 OHCA cases were included in the study. Out of these, 66 % (n=311) were defibrillated by the EMS, 16% (n=77) by a first responder and in 17% (n=81) the first shock was delivered by a public AED. In 33% (n=27) the public AED was a part of the PAD program. Survival to 1-month was 33 % in cases were defibrillation was performed by the EMS (n=103), 33% if defibrillation was performed by a first responder (n=25) and 66 % (n=55) if a public AED was used. Defibrillation by EMS and first responders in patients suitable for PAD decreased over time[[Unable to Display Character:   ]]from 93% to 73 %. Concurrently, defibrillation by public AEDs increased from 7% to 27% during the study period.

Conclusion:
[[Unable to Display Character:   ]]Public AEDs significantly contributes to survival in OHCAs suitable for PAD in Stockholm County, demonstrated by a 1-month survival of 66%. In this patient population, a public AED is used in 30% of all cases and with increased use of AEDs, PAD might challenge the potential gain from EMS and first responder systems.
Abstract 320: Decreasing Intraosseous Pressure and Increasing Respiratory Variability Track Fluid Volume Reduction in a Porcine Hypovolemia Model
Authors: Frascone Ralph J , Salzman Joshua G , Bliss Peter , Adams Alex , Wewerka Sandi S , Dries David J
Published: April 2024

Objectives:
Central venous pressure (CVP) provides an invasive and imprecise but accepted method for estimating fluid volume status. Intraosseous (IO) pressure monitoring may provide an alternative to CVP. To investigate this possibility, we measured intraosseous pressure changes in a porcine model during a hemorrhagic shock protocol.

Methods:
Our preparation included placement of femoral artery and central venous pressure lines. IO access was obtained by standard technique (EZ-IO, Vidacare Corporation, San Antonio, TX) to monitor pressures in the femur, humerus and tibia. All pressure signals were transmitted to a data acquisition system (Dataq Instruments,Inc., Akron, OH). To create vascular fluid volume changes, 17% of each pig’s estimated total blood volume was bled every 10 minutes until physiologic signs of hemorrhagic shock were recorded (mean arterial pressure <50 mmHg; tachycardia >150/min). To estimate fluid volume status, we tracked changes in absolute arterial, venous and IO pressures. As increasing respiratory variability is an accepted indicator of developing hypovolemia, we evaluated pressure variability due to respiration in all pressures after each 10 minute bleed period using the following formula: Δsystolic pressure/pulse pressure.

Results:
A hypotensive state was achieved in all six animals after bleeding each animal to 66.1±11.7% (1706.57±210 ml) of their estimated baseline fluid volume. Arterial, CVP and all IO mean pressures decreased at a constant rate. The proportional decrease pre/post bleed (mmHg) was not statistically different among all pressures: arterial 78.5→ 34.0 (-57%), humerus 17.9 → 6.5 (-64%), femur 17.1 → 9.8 (-43%), tibia 14.8 → 8.4 (-43%), CVP 6.6→ -0.9. The respiratory variability ratio increased in arterial, CVP and IO pressures to a similar extent and rate from 0.2 to 0.8 as the hypovolemic state developed.

Conclusions:
IO pressure decreased consistently at each IO site in this hemorrhagic shock model, indicating IO pressures can be tracked as indicators of change in fluid volume status. Increasing variability in IO pressure during the respiratory cycle was also associated with decreasing vascular fluid volume. IO pressure appears to be equivalent to CVP as an indicator of fluid volume status.
Abstract 329: High Volume Femoral Vein Infusion Significantly Increases EtCO2 During Prolonged CPR
Authors: Lampe Joshua W , Bratinov George , Weiland Theodore , Garcia Josiah D , Illindala Uday , Becker Lance B
Published: April 2024

Introduction:
Animal research has suggested that inducing therapeutic hypothermia during the arrest period (e.g. during chest compressions) may provide more benefit than inducing hypothermia after return of spontaneous circulation. Hypothermia induction technologies can be divided into two classes: technologies that require volume infusions, and technologies that do not. We hypothesize that a prolonged cold volume infusion during ongoing CPR will alter CPR hemodynamics, particularly venous return of blood to the heart.

Methods:
Eighteen temperatures were monitored in 24 domestic swine (~30 Kg) during intra-arrest hypothermia induction with ongoing CPR. Mechanical chest compressions and hypothermia induction were started after ten minutes of untreated VF. Chest compressions were performed at a rate of 100 per minute and a depth of 1.25 inches for 60 minutes. Hypothermia induction techniques included: control, femoral vein cold saline infusion, femoral vein ice slurry infusion, carotid cold saline infusion, carotid ice slurry infusion, nasopharyngeal cooling, heat exchange catheter cooling, and blanket cooling. The experiment was terminated after 60 minutes of chest compressions and cooling.

Results:
3 Liter femoral vein (FV) infusions of cold saline and ice particulate slurry at a rate of ~ 75 ml/min significantly increased EtCO2 during CPR at times 20-30 min (ETCO2_FV = 29.63 mmHg vs. ETCO2 = 22.16 mmHg, p<0.05), 30-40 min (ETCO2_FV = 23.8 mmHg vs. ETCO = 13.94 mmHg, p<0.05), and 40-50 min (ETCO2_FV = 20.07 mmHg vs. ETCO2 = 10.69 mmHg, p<0.05), with a trend toward significance at 50-60 min (ETCO2_FV = 16.84 vs. ETCO2 = 8.26, p = 0.056). Carotid infusions of similar volumes at similar rates did not improve ETCO2 during prolonged CPR.

Conclusions:
High volume femoral infusions administered during CPR significantly increased measured values of ETCO2. While not definitive, this data supports the hypothesis that imposing a volume driven flow in the femoral vein during CPR improves venous return. Interestingly, imposing a similar flow through the carotid artery did not increase measured values of ETCO2. The interplay between volume infusions and chest compression generated blood flow requires further study.
Abstract 346: Predictors of In-Hospital Outcome After Primary PCI of Left Main Coronary Artery Acute Myocardial Infarction With Cardiogenic Shock
Authors: Matsuo Koshi , Ueda Yasunori
Published: April 2024

Background:
In patients with acute myocardial infarction (AMI) and cardiogenic shock, emergency revascularization improves long-time survival. However, predictors of in-hospital outcome after primary PCI of left main coronary artery (LMCA) AMI remain unclear.

Methods:
Consecutive 21 patients admitted to our hospital presenting Killip IV heart failure and occluded LMCA on emergent coronary angiogram were enrolled. We performed primary PCI of LMCA. Patients’ clinical background, angiographic findings, results of primary PCI, laboratory data, usage of circulatory supporting devices (IABP and PCPS), performance of distal protection or not, and elapsed time (from onset to reperfusion) were retrospectively examined. Patients who died in hospital and those who survived were compared.

Results:
Successful reperfusion was achieved in 21 (100%) patients; IABP was used in 21 (100%) but PCPS in 6 (29%) patients; and 13 (62%) patients survived but 6 (29%) patients died in hospital. Elapsed time (5.1±2.5 vs. 2.8±1.0 hours; p<0.05) was shorter in patients who survived than in those who died, and peak CK (15509±8686 vs. 6608±3613 U/l; p<0.05) and peak CK-MB (567±316 vs. 925±387 U/l; p<0.05) were higher in patients who died than in those who survived. And wide QRS in electro cardiogram was found more frequently in patients who died than in those who survived. In addition, we performed distal protection more frequently in patients who survived than in those who died.

Conclusion:
Short elapsed time and small infarct size were associated with good in-hospital outcome. Therefore, sooner primary PCI of LMCA should be an effective therapeutic strategy for LMCA AMI resenting cardiogenic shock. In addition, we should perform distal protection as possible as we can even in LMCA AMI cases.
Abstract 347: Experimental use of a Pediatric Fluid Resuscitation Model: Evaluating Test-retest Reliability and Inter-subject Variability
Authors: Parker Melissa J , Lee Frank M , Thabane Lehana
Published: April 2024

Introduction:
Health Care Providers (HCPs) report that manual techniques of intravascular fluid resuscitation are commonly used to deliver isotonic fluid to young children. At present, it is unclear how manual fluid resuscitation is optimally performed by HCPs. A non-clinical experimental setting can be used to evaluate HCP fluid resuscitation performance outcomes, however test-retest reliability is unknown.

Objectives:
To determine HCP test-retest reliability (repeatability) and inter-subject variability of fluid resuscitation performance outcomes to inform the design of future studies.

Hypothesis:
We hypothesized that good test-retest reliability would be demonstrated, but that significant inter-subject variability would exist.

Methods:
We conducted an interventional study involving 15 consenting HCP subjects from McMaster Children’s Hospital in Hamilton, Canada. Subjects were oriented to a non-clinical model of a 15 kg toddler. The model incorporated a 22-gauge IV catheter and extension tubing affixed to the hand in typical clinical fashion. Following a standardization procedure, subjects were asked to rapidly administer 600 mL (40 mL/kg) of 0.9% normal saline to the model using prefilled 60 mL syringes. Subjects were advised to consider that this was urgently required treatment for decompensated septic shock. Each subject repeated the intervention 5 times with a 10-minute washout period between trials. All testing was video recorded, with fluid administration time outcome data (in seconds) extracted from trial videos by two blinded outcome assessors. The primary outcome of fluid administration time test-retest reliability was analyzed by one-way ANOVA and ICC as per our a priori plan.

Results:
Differences in HCP fluid administration times are attributable to inter-subject variability rather than intra-subject variability based on one-way ANOVA analysis, F(14,60)=43.125 (p<0.001). Test-retest reliability of subjects was excellent, with ICC=0.97 [95% CI 0.95; 0.99] (p<0.001).

Conclusions:
Our findings demonstrate excellent test-retest reliability of HCP fluid resuscitation performance in an experimental setting involving a non-clinical model. Use of a single HCP trial in future comparative studies is justified.
Abstract 355: Autologous Cleavage of the GPIbalpha Receptor Promotes Platelet Dysfunction Following Trauma
Authors: Cardenas Jessica , Wang Willa , Baer Lisa , Matijevic Nena , Cotton Bryan , Holcomb John , Wade Charles
Published: April 2024

Background:
Trauma is the most common cause of death in individuals 0-50 years of age and is responsible for more year of life lost than cancer, heart disease, and stroke combined. One quarter of all trauma patients experience some degree of prolonged hemorrhage due to impaired blood clotting, or trauma-induced coagulopathy (TIC). Protein C activation and hyperfibrinolysis have been proposed as key drivers in developing TIC. While primary hemostasis is mediated by von Willebrand factor (vWF) binding to the GPIbα receptor on the platelet surface, tethering them to damaged endothelium. Whether this interaction is altered in TIC remains unexplored. Data from our laboratory has previously shown a significant reduction in platelet-vWF adhesion over time following injury as measured by platelet aggregation response to ristocetin. The aim of this study was to determine the mechanisms behind defective platelet-vWF adhesion in trauma patients.

Methods and Results:
We obtained samples from 25 transfused trauma patients on admission and at 3, 5, 12, 24, and 120 hours later. Expression of the GPIbα receptor on the platelet surface and circulating in the plasma was measured by flow cytometry and western blot, respectively. We observed a time-dependent decrease in platelet bound GPIbα receptor expression (p=0.01) which was accompanied by up to a 6-fold increase in GPIbα shed into the plasma. Due to its role in proteolytic regulation of platelet aggregation through cleavage of GPIbα, we then measured expression of tumor necrosis factor-α converting enzyme (TACE). Membrane-bound TACE was analyzed by flow cytometry on platelets and leukocytes. We found a significant increase in platelet-derived TACE compared to healthy controls (p<0.01) and over time in trauma patients (p<0.05). The highest expression of platelet TACE corresponded to the time at which we observed the lowest GPIbα expression and lowest platelet-vWF adhesion in these patients.

Conclusions:
These data suggest that upregulation of platelet-derived TACE results in increased proteolytic cleavage of the GPIbα receptor and reduced platelet-vWF adhesion. These results have important implications for the use of TACE inhibitors to promote effective primary hemostasis in severely injured patients.
Abstract 359: Clinical Decision Rule to Activate the Massive Transfusion Protocol for Severe Trauma Patients
Authors: Ogura Takayuki , Nakano Minoru , Nakamura Mitsunobu , Fujizuka Kenji
Published: April 2024

Background:
There is no clear activation criteria of the Massive Transfusion (MT) Protocol for severe trauma patients.

Objective:
To create the Clinical Decision Rule (CDR) of MT Protocol activation, using Traumatic Bleeding Severity Score (TBSS).

Method:
Single center retrospective study was performed. Severe trauma patients (Injury Severity Score >/= 16), who admitted to our center between 2010 and 2012 were enrolled. Initial TBSS and MT rate in each score of TBSS was calculated, and the area under the receiver operating characteristic curve (AUC) for MT were calculated. Those patients who were simple traumatic head injury or cardiopulmonary arrest on arrive were excluded.

Result:
There were 264 patients in this study. AUC for MT was 0.947. When TBSS was 12 pts or less, MT rate was 3.7% (3/162). When TBSS was from 13 pts to 16pts, MT rate was 36.7% (11/30). When TBSS was 17 pts or more, MT rate was 94.4% (68/72). When TBSS was 19 pts or more, all patients received MT.

Discussion:
It was reported that TBSS was superior to TASH Score or ABC Score (AHA ReSS 2012, ECTES 2103). According to the result of this study, the Low Risk Group for MT was patients whose TBSS was 12 pts or less, the Moderate Risk for MT was patients whose TBSS was from 13 pts to 16pts, and the High Risk Group for MT was patients whose TBSS was 17 pts or more. In reference to these risk classification, we propose the following CDR to activate the MT Protocol.

1:
Activate the MT Protocol in the High Risk Group 2. DO NOT activate the MT Protocol in the Low Risk Group 3. In the Moderate Risk, repeatedly assess the TBSS and prepare for MT enough

Conclusion:
We propose the CDR to activate the MT Protocol that we should carry out MT for the trauma patients whose TBSS is 17 pts or more.
Abstract 15842: Inhaled Nitric Oxide Improves Outcomes After Cardiac Arrest and CPR Above and Beyond Therapeutic Hypothermia in Mice
Authors: Kida Kotaro , Mandeville Joseph B. , Bloch Kenneth D. , Ichinose Fumito
Published: April 2024

Kotaro Kida, 2013 Finalist and Presenting Author
Abstract 9463: Clinical and Genetic Evidence for Angiotensin Converting Enzyme Inhibition to Prevent Postoperative Tachyarrhythmias After Congenital Heart Surgery
Authors: Smith Andrew H. , Flack English C. , Borgman Kristie Y. , Owen Jill P. , Fish Frank A. , Bichell David P. , Kannankeril Prince J.
Published: April 2024

Andrew H. Smith, 2013 Finalist and Presenting Author
Abstract 10170: Lipoprotein(a) Concentrations, Rosuvastatin Therapy, and Residual Vascular Risk: An Analysis from the JUPITER Trial
Authors: Khera Amit V. , Everett Brendan M. , Caulfield Michael P. , Hantash Feras M. , Wohlgemuth Jay , Ridker Paul M. , Mora Samia
Published: April 2024

Amit V. Khera, 2013 Finalist and Presenting Author
Abstract 17801: Investigating the Effects of Resveratrol on Chronically Ischemic Myocardium in a Swine Model of Metabolic Syndrome: A Proteomics Analysis
Authors: Sabe Ashraf A. , Sadek Ahmed A. , Elmadhun Nassrene Y. , Robich Michael P. , Sellke Frank W.
Published: April 2024

Ashraf A. Sabe, 2013 Finalist and Presenting Author
Abstract 18584: Alpha-2 Agonist Attenuates Ischemic Injury in Isolated Spinal Cord Neurons
Authors: Freeman Kirsten A. , Puskas Ferenc , Bell Marshall T. , Mares Joshua M. , Weyant Michael J. , Cleveland Joseph C. , Fullerton David A. , Meng Xianzhong , Herson Paco , Reece T. Brett
Published: April 2024

Kristen A. Freeman, 2013 Finalist and Presenting Author
Abstract 6: A 15-Year Spectrum of Resuscitation Outcomes: A Story of Success or Failure?
Authors: Abougergi Marwan S , Eid Shaker M , Albaeni Aiham , Chandra-Strobos Nisha
Published: April 2024

Background:
Care strategies including automated defibrillators, improved emergency response systems, hypothermia and early revascularization have individually been shown to improve non-traumatic out-of-hospital cardiac arrest (OHCA) survival. We examined a national database to assess the cumulative impact of care change on outcomes in OHCA over a period of 15 years.

Methods:
We used the Nationwide Inpatient Sample, the largest nationally representative inpatient database, to calculate outcomes every 5 years from 1995 to 2010. Patients with an ICD-9 CM code for a principle diagnosis of cardiac arrest were included. Patients with any diagnosis of trauma were excluded. Admission rate was calculated using the July 1 population census estimate for each year. In-hospital mortality rate was adjusted for age, sex and Charlson comorbidity index taking year 2010 as a reference. All charges were adjusted for inflation using the consumer price index.

Results:
From 1995 to 2010, adjusted in-hospital mortality for OHCA has worsened. On subgroup analysis, mortality has improved when the coded presenting rhythm was Ventricular fibrillation (VF) and worsened when it was non-VF. The rate of poor neurologic outcome has increased with time. These changes have occurred despite the increasing use of hypothermia, coronary catheterization and stenting in all patients. Both the adjusted median hospitalization charges and the total OHCA economic burden have increased, especially after the year 2000.

Conclusions:
Comorbidity, age and gender adjusted in-hospital mortality from non-traumatic out-of-hospital cardiac arrest has increased over the past 15 years. Escalating resource utilization has yielded no improvement in survival for the majority of patients but has resulted in increased hospitalization costs, reaching a staggering annual economic burden of ~$1 billion in 2010. More in-depth review of care strategies is needed to improve survival and healthcare expenditure.
Cardiomyogenesis in the Adult Heart
Authors: Leri Annarosa
Published: April 2024

In recent years, a novel conceptual view has emerged; the heart is no longer considered a post-mitotic organ, but is viewed as an organ permissive for tissue regeneration mediated by exogenous and/or endogenous progenitor cells. One of the major biological controversies of the last decade has involved the plasticity of c-kit-positive bone marrow cells and their ability to acquire cell lineages different from the organ of origin. The possibility that c-kit-positive bone marrow cells can form cardiomyocytes and coronary vessels repairing the injured heart experimentally was accepted with great enthusiasm by cardiologists, resulting in the clinical implementation of bone marrow mononuclear cells in patients with acute and chronic ischemic cardiomyopathy. A series of negative animal studies, however, has challenged the concept of bone marrow cell transdifferentiation. Conflicting results may be attributed to several factors, including differences in the protocol of cell isolation and administration, animal model of cardiac injury, and methodologies employed for the characterization of the restored cardiac tissue. Importantly, these technical variables cannot account entirely for the reported failure of c-kit-positive bone marrow cells to form de novo myocardium after infarction. The molecular and functional heterogeneity commonly observed in hematopoietic stem/progenitor cells imposes the use of clonal assays for the characterization of c-kit-positive bone marrow cells at the single cell level. Population-based analyses of stem cell behavior fall short in the recognition of the mechanisms of replication and commitment that are unique to distinct progenitor cell subsets. Based on this approach, a restricted class of cardiopoietic c-kit-positive bone marrow cells with a specific molecular signature has been identified. These hematopoietic progenitors transdifferentiate into cardiomyocytes, resistance arterioles and capillaries, repairing the infarcted mouse heart. In contrast, the majority of c-kit-positive bone marrow cells retain their hematopoietic fate in vivo and form only occasionally scattered vascular structures. These findings offer a novel understanding of the long-term controversy on the plasticity and therapeutic efficacy of c-kit-positive bone marrow cells
Abstract 78: Multi-Criteria Evaluations for Improved Placement of Defibrillators: Preliminary Results
Authors: Ban Yifang , Fredman David , Jonsson Martin , Svensson Leif
Published: April 2024

Introduction:
When a person suffers an out of hospital cardiac arrest (OHCA), help within the first 3-5 minutes is critical for survival. In many cases, ambulances do not arrive within these critical minutes. Past studies show that early use of an Automatic External Defibrillator (AED) can improve the survival rate from 10% to 50%. Therefore Swedish Resuscitation Council has recommended placement of AEDs in public places so that the general public can assist when an OHCA is taking place. However, the defibrillators in Stockholm as well as in most parts of Sweden are financed and placed by individuals, companies or organizations at their own initiative. Where are the defibrillators most needed? Is the current placement of defibrillators suitable? These are the research issues for this study.

Hypothesis:
Can Multi-Criteria Evaluations (MCE) be used to determine the most suitable placements of AED based on historical data for OHCA and analysis of risk groups?

Method:
Census data on nighttime population (age and gender) over Stockholm in 250 m by 250 m grid were collected from Statistics Sweden. Data on previous OHCA in Stockholm during 2006-2012 were provided by the cardiology center of Södersjukhuset. Prior heart disease information was extracted from the Swedish OHCA database. MCE, a spatial analysis tool in GIS for decision support, were performed to determine the most suitable locations for placing defibrillators based on four different scenarios with different weights of the risk factors.

Results:
Preliminary results show that a number of areas in Stockholm are in need of more strategic placement of AEDs. The most suitable locations complement the existing defibrillators are presented in the first three scenarios. In scenario four, only based on the historical OHCA occurrences, the placements somewhat overlap with the existing defibrillators plus the need of additional AEDs in several areas. These results indicate that MCE is a promising tool to support decision-making on the placement of AEDs. Future research is planned to take into account more risk factors and to improve the data availability and quality.
Abstract 79: Impact of the 2010 Resuscitation Guidelines on CPR Quality During In-Hospital Cardiac Arrest
Authors: Beams Owen K , Leary Marion , Cinousis Marisa , Sheak Kelsey , Abella Benjamin
Published: April 2024

Background:
The 2010 resuscitation guidelines emphasize quality compressions, including a target depth of “at least 2 inches” (50 mm), and a target rate of “at least 100 compressions/min”. Studies have demonstrated that the guidelines update has positively impacted CPR performance in the pre-hospital setting, but no such data exist for in-hospital CPR quality.

Hypothesis:
We hypothesized that following the guidelines release, CPR data collected during in-hospital cardiac arrest events would demonstrate increased compression depth and rate, but that a lag period would exist prior to these observed changes.

Methods:
Chest compression data from consecutive cardiac arrest events at a single medical center were collected prior to the guidelines change between 1/2010-9/2010 and compared to data collected after the guidelines release from 11/2010-2/2013, using a CPR-sensing defibrillator (MRx QCPR, Phillips Healthcare). Data were compared both in aggregate and in sequential 4 month time periods to evaluate for change over time. Welch’s t-test was used to compare compression rate and depth means across time periods.

Results:
A total of 1,078 segments of CPR (30 sec each) performance were available for the pre-guidelines change period, and 1,652 30s segments for the post-guidelines release period. Mean compression rate and depth for the aggregate period following the guidelines release was increased (rate: 111.5 comp/min vs. 107.3 comp/min, p<0.001 and depth: 49.9 mm vs. 46.9 mm, p<0.001). Analysis for change over time found a consistent increase in rate after 4 months time and a lag-time of 16 months for a sustained increase in depth.

Conclusions:
Following the 2010 release of updated CPR guidelines, compression rate and depth increased in a cohort of in-hospital resuscitation events. However, a lag time of 16 months for a sustained compression depth increase demonstrates the possibility of delayed uptake of new guidelines.