tbuckley/cabot-search huggingface dataset:
Abstract Su902: Ability of Composite Magnetic Resonance Brain Imaging Scores to Predict Functional Outcomes in Survivors of Cardiac Arrest
Authors: Thuhien Nguyen, Nicolas Poilvert, Victor Lin, Hope Ukatu, Nassim Matin, Arielle Davis, Breana Taylor, Penelope Thomas, Monisha Sharma, James Town, Sarah Wahlster, Nicholas Johnson
Journal: Circulation (2024)

Background: Brain magnetic resonance imaging (MRI) has been examined for neuroprognostication (NP) after out-of-hospital cardiac arrest (OHCA). However, studies have focused on predicting poor outcomes of non-awakening and/or death. Recommendations for utilization of brain MRI in NP remain weak due to its subjective interpretation. Aim: We modified a previously published brain MRI score and examined our quantitated NP scores’ ability to predict good functional outcomes in OHCA survivors. Methods: We screened OHCA cases (2017-2023, Seattle Medic One registry) for patients who survived to hospital discharge and had brain MRIs performed 25 hours-7 days after arrest. Each MRI was reviewed by two adjudicators; a third reviewer served as tie-breaker. Reviewers were blinded to patient outcomes. Diffusion Weighted Imaging and Fluid Attenuated Inversion Recovery sequences were reviewed to score 35 neuroanatomical regions. Graded severity for estimated affected area (0 = zero; 1= &lt; 25%; 2 = 25-50%; 3 = 50-75%; 4 = &gt;75%) and binary (0 = not affected, 1 = affected) scores were tallied. Points were summed for a composite brain MRI score, “ NP score ”, possible range 0-214. Primary outcome was Cerebral Performance Categories (CPC) at hospital discharge (1-2: “independent”, 3: “dependent”, 4: “vegetative state”). Computational modeling employed folded normal distributions and Maximum Likelihood Estimation. Statistical analyses were Pearson’s, Spearman’s, ANOVA, Fisher LSD, t-tests. Results: Forty-two (42) adult patients were included (74% men, 55% Caucasian). Median NP score was 11.5 (IQR 41.5, n=42) overall, 2 (IQR=10, n=21) for independent versus 25.5 (IQR 36.5, n=10) for dependent patients, and 92 (IQR=81, n=11) for those in a vegetative state. NP scores strongly correlated with CPC [ r s (40) = .69, p&lt; .001 ], and were significantly different between CPC groups [F(2,39) = 32.66, p&lt; 0.001 ]. Interrater concordance for NP score was high (Pearson) r = .88 [r = .96; .95; .90; .71]. Conclusions: Our NP score correlated well with good functional outcomes in OHCA survivors, and (1) identified distinct thresholds that well-separate functional outcome groups and (2) had very strong concordance rate among four pairs of adjudicators. NP score-based predictive modeling differentiates functional outcomes beyond good versus poor dichotomy and may help providers and family anticipate recovery potential.
Abstract Su403: Iterative Simulation to Optimize Mechanical CPR Device Application
Authors: Caroline Lauer, Kelsey Wilhelm, Elizabeth Leon, Kim Howard, Shane Cook, Shira Schlesinger
Journal: Circulation (2024)

Mechanical chest compression devices (MCDs) are commonly used for in-hospital and emergency department (ED) cardiac arrest resuscitation. Manufacturer guidelines and educational materials demonstrate that in the prehospital setting, MCDs can be deployed with an interruption in CPR of less than 15 seconds. No similar materials exist for the in-hospital environment, where observational studies have noted median CPR interruptions of up to 40 seconds for MCD deployment. With the integration of extracorporeal CPR (eCPR) into OHCA systems of care, the need to transfer patients with ongoing CPR to MCDs in the ED is growing. To develop a hospital-specific procedure for receiving a patient in cardiac arrest and deploying the MCD with minimal no-flow time. We used an iterative participatory design process to develop a procedure for receiving patients in cardiac arrest from Emergency Medical Services (EMS). Tasks included transferring a patient, replacing defibrillator pads, and deploying the hospital MCD with minimal no-flow time. Participants including ED physicians, nurses, and respiratory therapists performed a series of simulations using a high-fidelity manikin, resuscitation equipment, and an MCD. Simulations were followed by focused debriefings, participant-directed modification of the working procedure, and repeat simulation until participants expressed satisfaction with the procedure. Participant roles were shuffled after each round. The primary outcome was the duration of CPR interruption required to deploy the MCD; change in this time over successive iterations was assessed using a Wilcoxon signed-rank test. The final procedure described a sequence of steps and responsibilities that participants deemed efficient and reproducible. Through seven simulation-debriefing cycles, CPR interruption associated with MCD deployment decreased from 19 to 10 seconds (p = 0.033). The most common failure modes that participants corrected during modifications involved needed equipment that was out of reach, obstructed provider positioning, and poorly defined roles. On subsequent days, two additional groups of on-shift ED providers deployed the MCD in less than 15 seconds following the developed procedure. Using an iterative design process, we created an MCD deployment procedure that minimized CPR interruptions and was acceptable to hospital staff. This represents an effective, low-cost methodology to design a process for transfer of care during CPR and MCD deployment.
Abstract Su503: Relationships Between Quantitative ECG Measures and Defibrillation Success in Early Ventricular Fibrillation
Authors: Rameen Forghani, Jorge Gumucio, James Menegazzi, David Salcido
Journal: Circulation (2024)

Introduction: Rapid termination of ventricular fibrillation (VF) has long been recognized as the cornerstone of effective cardiac arrest resuscitation. In recent years, amplitude spectral area (AMSA) has been shown to be highly associated with defibrillation success, and AMSA has been experimentally used to personalize defibrillation timing and strategy. However, questions remain about whether the interpretation of AMSA holds uniformly in varied conditions, such as ultra-early or prolonged cardiac arrest or after anti-arrhythmic administration. Hypothesis: AMSA is greater after 20 seconds of untreated VF compared to 50 seconds of untreated VF; a higher AMSA predicts greater first-defibrillation success. Methods: VF was induced in adult swine (n = 3) with a bipolar pacing catheter placed in the right ventricle. Animals were randomized to 20- or 50-second-long episodes of VF (n = 123), followed by standard 150 J biphasic defibrillation. In MATLAB, AMSA was calculated as the summed product of frequency and square root of power after Fast Fourier Transform for the four second period of VF immediately prior to defibrillation. Results were analyzed by a two-sided Chi-squared test or ANOVA with Tukey’s HSD in R; a p-value &lt; 0.05 was considered significant. Results: First shock success was lower in the 20-second-VF group compared to the 50 second group (31/78 (39.7%) vs 31/45 (68.8%), p = 0.003). The AMSA at 20 seconds was significantly higher for successful compared to unsuccessful first defibrillation (8.20 vs. 7.31 mV-Hz, p = 0.034). The AMSA at 50 seconds was not statistically different between successful and unsuccessful defibrillations (6.32 vs. 5.67 mV-Hz, p = 0.470). Evaluating the AMSA after a duration of VF irrespective of shock success, AMSA was higher at 20 seconds compared to 50 seconds (7.66 vs 6.12 mV-Hz, p &lt; 0.001). Conclusion(s): AMSA decreases from 20 to 50 seconds of untreated VF, and higher AMSA at a given time point is associated with greater first defibrillation success. However, first defibrillation success was higher after 50 seconds of untreated VF compared to 20 seconds, raising questions about special cases, such as edge effects, that may influence AMSA interpretation.
Abstract Su302: Impact of Time to Defibrillation on Mortality after In-Hospital Cardiac Arrest
Authors: Jordan Shinn, Sairamya Bodempudi, Eileen Howarth, Theodore Maglione, James Coromilas
Journal: Circulation (2024)

Background: In-hospital cardiac arrest occurs in 290,000 patients annually in the United States, with less than 20% of these arrests featuring a shockable presenting rhythm. The three-phase model of CPR is separated into the electrical phase which occurs in the first 4 minutes, the circulatory phase which includes minutes 4-10, and the metabolic phase which is greater than 10 minutes from arrest onset. Defibrillation during the electrical phase has been proven to improve survival by approximately 50%. Current guidelines recommend defibrillation within the first 2 minutes of arrest in those with a rhythm of VT/VF. The purpose of this study was to determine the effect of time to defibrillation on mortality in patients with shockable rhythms. Methods: Full-disclosure rhythm strips for all cardiac arrests in non-ICU patients on telemetry were reviewed from Feb 2019 to April 2023. Time to defibrillation of shockable rhythms (VT/VF) was determined from the telemetry data and corresponding defibrillator data from the Zoll CodeNet electronic system. Results: We identified 32 of the 186 patients with cardiac arrest while on telemetry presenting with pulseless monomorphic VTor polymorphic VT/VF. The average time to defibrillation was 4.8 min ± 2.7 min. 34% of patients were defibrillated in 4 minutes or less from the onset of the arrythmia, 31% were defibrillated in more than 4 minutes from the onset of the arrythmia, and 34% were not defibrillated. Patients defibrillated in 4 minutes or less had a significantly lower mortality of 36.4% compared to a 50% mortality of those defibrillated in more than 4 minutes and 90.9% mortality in those not defibrillated (p&lt;0.05).The patients who were not defibrillated were determined to have ongoing VT or poly VT/VF until telemetry was removed and the Zoll defibrillator pads were applied. They were ultimately deermined ot have PEA and were not shocked. Conclusions: Patients defibrillated in 4 minutes or less from the onset of a sustained shockable arrythmia experienced significantly lower mortality during hospitalization compared to those who were defibrillated in more than 4 minutes or were not defibrillated. 34% of patients with a shockable rhythm were not defibrillated due to a diagnosis of PEA after the Zoll pads were placed. Patients with sustained VT/VF causing in-hospital cardiac arrest should be defibrillated as soon as a defibrillator can be applied. Telemetry data should be clearly communicated to the code team.
Abstract Su501: Feasibility and Implications of Electrocardiogram-based Prediction of Incessant Refractory Ventricular Fibrillation
Authors: Jason Coult, Julia King, Heemun Kwok, Shiv Bhandari, Jennifer Blackwood, Nicholas Johnson, Michael Sayre, Mohamud Daya, Thomas Rea, Peter Kudenchuk
Journal: Circulation (2024)

Background: Refractory ventricular fibrillation (R-VF) patients, defined as requiring ≥ 3 shocks during resuscitation of OHCA, have relatively poor outcomes. Prior studies have predicted R-VF using the ECG, suggesting potential to guide early patient-specific treatment for R-VF. However, R-VF comprises multiple phenotypes with distinct defibrillation response profiles: Incessant VF (no shocks terminate VF), recurrent VF (all shocks terminate VF but VF recurs), or mixed VF (shocks variably terminate VF). These phenotypes may have distinct prognoses, and may also respond differently to R-VF treatments such as early antiarrhythmics, modified vasopressor dosing, alternative defibrillation strategies, or expedited invasive interventions. Early prediction of specific R-VF phenotype could potentially improve outcome through preemptive targeting of treatment to individual phenotype. Aim: We sought to predict incessant R-VF using machine learning analysis of the defibrillator ECG. Methods: We performed a retrospective study of adult VF OHCA treated by EMS from 2006–2019 in King County WA. We linked a clinical OHCA registry with defibrillator recordings to evaluate ROSC and survival to hospital discharge by VF type (non-refractory; or incessant, recurrent, or mixed R-VF prior to the third shock). To predict incessant R-VF specifically, we used a series of four 2-s ECG segments from each patient within 60s surrounding the first shock. Patients were randomized 65%/35% for training/test. A support vector machine classifier was trained to predict subsequent incessant R-VF using ECG scalograms. Algorithm performance was assessed by area under the receiver operating characteristic curve (AUC) and by sensitivity at &gt;75% specificity. Results: Of 1111 included VF patients, median age was 62, 241 (22%) were female, 658 (59%) were refractory (≥ 3 shocks), 800 (72%) achieved ROSC, and 520 (47%) survived. The incessant R-VF phenotype accounted for 10% (N=116) and had worse ROSC and survival compared to recurrent R-VF and non-refractory patients (Table). Training and test AUCs to predict incessant R-VF were 0.77 (95% CI: 0.72–0.82, N=723) and 0.76 (95% CI: 0.66–0.82, N=388) respectively. Test sensitivity and specificity were 64% and 76%. Conclusion: Refractory VF comprises distinct phenotypes with disparate outcomes. Incessant R-VF has notably poor prognosis. Machine learning may be able to predict incessant R-VF, potentially guiding preemptive, patient-specific treatments to improve outcome.
Abstract Su1205: The Effect of Targeted Temperature Management on Five-Year Mortality in Comatose Out-of-Hospital Cardiac Arrest Survivors: A Real-World Experience
Authors: Arezou Tajlil, Amr Abdelradi, Wassim Mosleh, Sharma Kattel, Zaid Al Jebaje, Umesh Sharma
Journal: Circulation (2024)

Background: Hypothermia-Induced Targeted Temperature Management (TTM) is a neuroprotective treatment after the return of spontaneous circulation (ROSC) in comatose survivors of out-of-hospital cardiac arrest (OHCA). However, its effectiveness in all patient subpopulations is debated. While short-term survival has been well studied, the impact of TTM on long-term survival is still unknown. Methods: In a prospective cohort study, 98 comatose survivors of non-traumatic OHCA were recruited from four tertiary-level hospitals in Buffalo, Western New York and followed up for five years. Patients with active cancer, infection, cardiac pathology or surgery in three-month prior to presentation, were excluded. Cardiac arrest characteristics, demographics, comorbidities, and therapeutic interventions were recorded. According to TTM protocols, a target body temperature of 33°C was reached and maintained for 24 hours using either an intravascular cooling catheter or a surface cooling system. This was followed by gradual controlled rewarming over 12-24 hours to normothermia. Factors associated with the receipt of TTM were determined. The effect of TTM on five-year survival was studied using cox-regression analysis. Results: Among comatose patients with mean age of 60.1±14.9 years, 49% received TTM. Females were significantly less likely to receive TTM (35.1% vs 59.3%, p=0.021). In TTM group, the time to ROSC was significantly longer: median [IQR] 14.5 mins (5-19.7) vs 20 mins (12-27), p=0.018. TTM group was more likely to have a history of coronary artery disease (CAD) (12.5% vs 35.4%, p=0.009). Overall, 5-year mortality did not differ significantly between TTM vs. non-TTM: 72.9% vs 66.0%, (HR: 1.134, 95% CI: 0.705-1.826, p=0.603) in univariate and multivariate Cox-regression analysis (Table 1). Conclusion: While females are less likely to receive TTM treatment, TTM is more likely to be used in patients with a longer time to ROSC and a history of CAD. The overall five-year survival remains high in both treatment groups in all eligible patients, as well as in shockable and non-shockable rhythm groups studied separately. Larger cohort studies are needed to determine the patients who may benefit most from TTM.
Abstract Su205: Using Emergency Medical Services Monitors for Cardiac Arrest Patients in the Emergency Department is Associated with Faster Initial Rhythm Analysis and Defibrillation
Authors: Rahul Ramraj, Elaine Chen, Adrian Puentes, Ghania Haddad, Molly Pineo, Elizabeth Young, Timmy Li, Lance Becker, Daniel Rolston, Daniel Jafari
Journal: Circulation (2024)

Introduction: The 2020 American Heart Association guidelines for Cardiopulmonary Resuscitation (CPR) emphasizes the importance of high-quality CPR and early defibrillation in improving cardiac arrest (CA) survival. Using our emergency department (ED) CA video review registry, we can capture metrics to reliably assess the effectiveness of different approaches to CA management. Goals/Hypothesis: We propose that emergency medical services (EMS) pads and defibrillators should be used to initially analyze cardiac rhythm in the ED. We hypothesize that this “EMS Equipment” approach is associated with shorter time to first ED rhythm detection and defibrillation, higher chest compression fraction (CCF), and improved return of spontaneous circulation (ROSC) rates. Methods: This is a single center, retrospective cohort study using our CA video review registry between 10/03/2018 – 2/20/2024. Atraumatic, out-of-hospital CA patients ≥18 years were included while patients arriving to the ED with ROSC were excluded. The “EMS Equipment” group utilized EMS pads and defibrillators while the “ED Equipment” group utilized ED pads and defibrillators for the first ED rhythm analysis. Wilcoxon rank sum tests were used to assess differences in time to first rhythm check and first defibrillation among the two groups. Chi-square tests were used to assess whether the proportions of patients achieving above median CCF, ROSC, survival to admission and discharge in the two groups were different. Results: A total of 247 patients were included in the analysis with 69 patients in the EMS Equipment group (27.9%) and 178 patients in the ED Equipment group (72.1%). The EMS Equipment group had a shorter median time to first ED rhythm detection (96 vs. 255 seconds, p &lt;0.00001). Among the 63 patients defibrillated in the ED, the EMS Equipment group had a shorter median time to first ED defibrillation (103 vs. 413 seconds, p = 0.0024). There was no significant difference in CCF, ROSC rates, survival to admission or discharge. ROSC was achieved in 36% of cases. Conclusion: In conclusion, initial rhythm analysis with EMS pads and defibrillators was associated with shorter time to initial ED rhythm detection and defibrillation, but not improved CCF, ROSC rates, and survival. Larger studies are needed to verify these exploratory results in more diverse settings.
Abstract Su1206: Reduced Time to Goal Therapeutic Hypothermia With Implementation of a Post Cardiac Arrest Consult Service
Authors: Sydney Palka, Ben George, Jenna Gonillo, Lisa Cardamone, Samantha Helmy, Jeronimo Cardona, Samantha Escobar, Daryl McHugh, Debra Roberts, Imad Khan
Journal: Circulation (2024)

Introduction: Critical care after advanced cardiac life support can be pivotal for survival and outcomes in patients with out-of-hospital cardiac arrest (OHCA). Prior studies have demonstrated improvements in survival after OHCA with shorter door-to-therapeutic hypothermia (TH) initiation times. Post-cardiac arrest consult teams (PCACT) can facilitate TH to goal 33°C and other aspects of post-arrest care. However, the effects of such a service on TH have not been consistently quantified. Hypothesis: More OHCA patients would undergo TH and reach goal temperature sooner following implementation of a PCACT. Aims: We aim to evaluate the effectiveness of a PCACT in optimizing TH in survivors of OHCA. Methods: We conducted a retrospective chart review of 305 patients admitted between January 1, 2021 and December 31, 2022. Implementation of a dedicated PCACT, comprised of a neurointensivist and an advanced practice provider or neurocritical care fellow, occurred on January 1, 2022. The PCACT was active on weekdays only. One year before and after this date were designated as “pre-PCACT” and “post-PCACT”, respectively. De-identified patient demographics, clinical features of cardiac arrest, and TH data were collected and compared using Wilcoxon rank-sum and Chi-squared tests for continuous and categorical variables, respectively. Results: Of the 305 patients admitted during the study period, 149 were in the pre-PCACT group and 156 were in the post-PCACT group. Baseline demographics between the two groups were similar except that the post-PCACT group had more patients with non-shockable rhythms (64% vs. 54%, p =0.001). Patients were not cooled to 33°C more frequently (50 vs. 52%) pre- or post-PCACT. TH to 33°C was performed in 156 (51%) patients, 78 patients (50%) pre- and post-PCACT implementation. There were no baseline demographic or temperature differences between the two groups amongst patients undergoing TH to 33°C. Post-PCACT patients were quicker to reach 33°C (1.6 vs. 3 hours, p =0.001). After PCACT implementation, this difference was noted during weekdays but not during weekends (1.3 vs. 2.7 hours, p =0.05).There were no differences in survival or neurologic outcomes pre- and post-PCACT introduction, nor between patients who were or were not cooled to 33C. Conclusion(s): Implementation of a PCACT may streamline care to reduce time to goal temperature during TH. However, further study is required to determine whether a PCACT can improve outcomes.
Abstract Su1202: The utility of post cardiac arrest temperature control protocol according to the severity of hypoxic encephalopathy based on amplitude-integrated electroencephalography findings
Authors: Ken Inoue, Kazuhiro Sugiyama
Journal: Circulation (2024)

Introduction: The TTM2 trial showed that active fever prevention below 37.5°C and hypothermia at 33°C had similar outcomes in out-of-hospital post cardiac arrest patients. However, the patients in the trial had mild hypoxic encephalopathy, and the effects of hypothermia may vary with its severity. We previously reported that amplitude-integrated electroencephalography (aEEG) findings after the return of spontaneous circulation can be used to categorize the severity of hypoxic encephalopathy (Crit Care. 2018;22:226). In September 2022, we adopted a new temperature control protocol wherein the target temperature was set based on aEEG findings. This study examined changes in outcomes before and after implementing this new protocol. Methods: We assessed out-of-hospital cardiac arrest patients who received post cardiac arrest care in our emergency intensive care unit between March 2021 and February 2024. We divided the patients into two groups: before (B) and after (A) the introduction of the new protocol. We classified the patients into categories 1 (C1) to 4 (C4) based on the severity of hypoxic encephalopathy (Figure 1). All patients in group B were treated with hypothermia at 34°C. In group A, patients in C1 were treated with active fever prevention, and those in C2–C4 received hypothermia at 34°C (Figure 2). Primary outcome was favorable neurological outcomes (cerebral performance categories of 1 or 2) at hospital discharge. Secondary outcome was the duration of mechanical ventilation. Results: A total of 160 patients were included. The median age was 62 years and 105 (66%) patients had cardiac etiology. Fifty-five (34%) patients underwent extracorporeal cardiopulmonary resuscitation. The median cardiac arrest time was 29 min. Groups B and A comprised 57 and 103 patients, respectively. C1 category comprised 20 and 28 patients in groups B and A, respectively. The rate of favorable neurological outcomes was 35% in both B and A groups (p=1.00). Regarding C1 patients, the rates were 90% and 86% in B and A groups (p=1.00). Median duration of mechanical ventilation was 5 and 3 days in group B and A, respectively (p=0.11). Conclusion: Neurological outcomes before and after introducing the new protocol were similar. Management of patients with mild hypoxic encephalopathy can be simplified with active fever prevention. A temperature control protocol based on the severity of hypoxic encephalopathy using aEEG findings is feasible for emergency physicians.