tbuckley/cabot-search huggingface dataset:
Abstract Su304: The Effect of Time to DC Shock on Return of Spontaneous Circulation in Out-of-Hospital Cardiac Arrest with Recurrent Shockable Rhythm
Authors: Emad Awad, Brent Klapthor, Michael Morgan, Scott Youngquist
Journal: Circulation (2024)

Objective: The optimal timing for defibrillation attempts in out-of-hospital cardiac arrest (OHCA) patients with recurrent shockable rhythms [ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT)] is uncertain. This study examined the association between "time to DC shock" and the return of spontaneous circulation (ROSC) in OHCA patients with recurrent shockable rhythms. Methods: This was a retrospective analysis of data from the Salt Lake City Fire Department (SLCFD) from 2012 to 2023. Rhythm-filtering technology, used since 2012, enabled real-time and accurate interpretation of cardiac rhythms during CPR, with local protocols allowing early defibrillation for recurrent VF/ pulseless VT cases. Patients who experienced four or five episodes of shockable rhythms and received defibrillation were included. Generalized estimating equation (GEE) analysis was used to evaluate the association between time to shock preceding recurrent defibrillation and ROSC. Results: A total of 142 patients were included, with a mean age of 59.7 ± 15 years; 105 (73.9%) were male, 63 (44.4%) arrested in public locations, and 101 (71.1%) had witnessed arrests. Adjusted GEE analysis revealed that longer time to shock was associated with lower odds of achieving ROSC (OR: 0.81, 95% CI: 0.72–0.93, p = 0.005). Every one-minute delay in defibrillation is predicted to decrease the likelihood of achieving ROSC by 19%. Conclusion: In patients with recurrent shockable rhythms, every one-minute delay in delivering a shock was associated with a statistically significant 19% reduction in the chance of achieving ROSC. This finding highlights the importance of reducing the time to defibrillation in managing recurrent shockable rhythms and suggests reevaluating the current recommendation of two-minute intervals for rhythm check and shock delivery.
Abstract Su906: Patient and Arrest Characteristics Associated with Rearrest and Mortality Following Out of Hospital Cardiac Arrest
Authors: Eric Burguera-Couce, Pam Pam Gwo, Julie Nichols, Joseph Piktel, Kenneth Laurita, Lance Wilson
Journal: Circulation (2024)

Background: Cardiac rearrest post-return of spontaneous circulation (ROSC) is a critical concern in emergency care, as it is associated with worse outcomes. Patient characteristics and arrest factors associated with rearrest remain poorly understood, making predicting rearrest after out of hospital cardiac arrest (OHCA) challenging. Aim: To examine rearrest patterns, identify patient-specific risk factors for rearrest, and assess the impact of rearrest on patient outcomes. Hypothesis: Patients that experience rearrest after OHCA will have greater cardiac comorbidities, unfavorable arrest characteristics, and greater mortality. Methods: We performed an observational single-site clinical trial of consecutive adult EMS OHCA patients with ROSC (1/01/2018 to 3/31/24). EMS reports, continuous EMS ECG recordings, and electronic health records were analyzed to determine rearrest occurrence at any time during EMS and ED care. Patient demographics, comorbidities, and arrest/rearrest characteristics were determined. The primary outcome was survival at 6 months. Statistical significance was determined using Chi-square and logistic regression (LR) analyses. Results: We examined 344 patients with OHCA and ROSC, of whom 173 patients rearrested and 171 did not. Patients experiencing rearrest were older (p&lt;0.003) and more likely to be female (p&lt;0.013). They were also more likely to have ED resuscitation medications and interventions (epinephrine, amiodarone, lidocaine, defibrillation, all p&lt;0.001) and a higher incidence of underlying cardiovascular comorbidities, including HTN and CAD (p&lt;0.03). Notably, PEA and asystole were the most common rearrest rhythms, and time from arrest to ROSC was greater (30±16 vs. 25±15 min, p&lt;0.007) in rearrest patients vs. those who did not rearrest. Patients with rearrest were less likely to receive TTM (p&lt;0.003) and importantly, had higher rates of in-hospital and six-month mortality (both p&lt;0.001). In a LR model, no rearrest (OR 2.4, 1.1-5.2), shockable arrest rhythm (OR 9.3, 4-22), female sex (OR 3.3, 1.6-6.5), and therapeutic hypothermia (OR 3.3, 1.7-6.4), were associated with survival (all p&lt;0.04). Conclusions: Rearrest is independently associated with mortality. Increased age, male sex, and underlying cardiac comorbidities were associated with rearrest. Patient and arrest characteristics may predict rearrest. Improved understanding of why these factors promote rearrest will be important to prevent rearrest to enhance OHCA outcomes.
Abstract Su904: The association between base excess on arrival at the hospital and neurological outcome of adult out-hospital cardiac arrest: observational study
Authors: Ryuta Onodera, Norihiro Nishioka, Takeyuki Kiguchi, Tetsuhisa Kitamura, Taku Iwami
Journal: Circulation (2024)

Background: The relationship between base-excess (BE) values, which take into account the time interval from cardiac arrest to blood test, and neurological outcome after out-of-hospital cardiac arrest (OHCA) is not well understood. The purpose of this study was to evaluate the association between BE on arrival at the hospital and neurological outcomes in OHCA patients. Methods: The CRITICAL study, a prospective, multicenter observational study in Osaka, Japan, registered consecutive OHCA patients who were transported to 16 participating critical care centers from 2012 to 2021. We included adult patients aged 18 years with witnessed OHCA whose BE values on hospital arrival was available, and divided patients into quartiles based on BE values of initial blood test on arrival at the hospital: Q1 (BE ≤ −21.1 mmol/L), Q2 (−21.1 &lt; BE ≤ −15.7 mmol/L), Q3 (−15.7 &lt; BE ≤ −10.4 mmol/L), and Q4 (BE &gt; −10.4 mmol/L). The primary outcome was one-month survival with favorable neurological outcome, defined as cerebral performance category scale 1 or 2. Results: A total of 23,854 patients were registered, and 6,066 of them were eligible for analyses. Neurologically favorable outcome was the lowest in the Q1 group (3.2% [49/1,528]), followed by the Q2 (4.7% [70/1,493]), Q3 (9.8% [148/1,515]), and Q4 (23.5% [359/1,530]) group. In the multivariable logistic regression analysis, the adjusted odds ratio of Q1 compared with Q4 for one-month favorable neurological outcome was 0.13 (95% CI 0.090–0.18). The proportion of one-month favorable neurological outcome decreased progressively across decreasing quartiles (p for trend &lt; 0.001). In subgroup analysis, there was an interaction between presence of return of spontaneous circulation (ROSC) before blood test and neurological outcome (p for interaction &lt; 0.001). The neurological outcome worsened as the BE values decreased among those who achieved ROSC before the blood test (p for trend &lt; 0.001), but not in those without ROSC (p for trend = 0.078). There was not a significant interaction between BE values without ROSC before blood test and time from witness to blood test (p for interaction = 0.501). Conclusions: We demonstrated that lower BE values at hospital arrival were associated with worse neurological outcome. The BE values may be one of the effective prognostic indications for neurological outcome, especially in OHCA patients with ROSC before hospital arrival.
Abstract Su507: Occurrence of Fibrillation in Out-of-hospital Cardiac Arrest Patients Presenting in a Non-shockable Rhythm when Treated with an Automated External Defibrillator
Authors: Chenguang Liu, Mengqi Gao, Stacy Gehman, Dawn Jorgenson
Journal: Circulation (2024)

Background: Most out-of-hospital cardiac arrest (OHCA) patients who are initially treated with an automated external defibrillator (AED) and present in a non-shockable rhythm never receive a shock. This analysis reports on patients who presented in a non-shockable rhythm when the AED was initially applied and later transitioned into a shockable rhythm. Methods: Data from a convenience group of OHCA patients treated with a Philips HeartStart Home, Onsite or FRx AED were included. The AEDs were the first defibrillator on scene either in home, in public access or by a BLS team. Application of any medication during AED use was unlikely. Each patient’s heart rhythms were reviewed by an expert. All patients whose initial rhythm was non-shockable but later received at least one shock were identified and the rhythms were analyzed. Results: Out of 876 patients, 322 (36.8%) received at least one shock, of which five patients (1.6%) presented in a non-shockable rhythm and were later shocked. Three patients presented in an organized rhythm. The first patient degraded into Torsade de Pointe as shown in Figure 1; the post-shock rhythm was organized. The second patient received no CPR and A-V pacing was observed in the ECG recording. The pacing stopped when the rhythm transitioned into VF and restarted post shock. The third patient transitioned into VF during chest compressions and the post-shock rhythm was asystole. The remaining two patients presented in asystole and the rhythm evolved to fine VF after receiving chest compressions. After defibrillation, their rhythms returned to asystole. Conclusions: For OHCA patients treated with an AED, presenting in a non-shockable rhythm and later transitioning into a shockable rhythm is rare but possible. Lay-responder CPR may play a role in rhythm evolvement. The impact of rhythm changes on survivability of these patients is unknown.
Abstract Su701: The Influence of Public Assistance Among Patients Who Received Extracorporeal Cardiopulmonary Resuscitation after Cardiac Arrest in Japan
Authors: Takeshi Nishimura, Akihiko Inoue, Masafumi Suga, Satoshi Ishihara
Journal: Circulation (2024)

Background: This study aimed to evaluate the influence of public assistance on patients with out-of-hospital cardiac arrest (OHCA) who received extracorporeal cardiopulmonary resuscitation (ECPR) in Japan. Methods: We conducted a secondary analysis of data from the SAVE-J II study, a retrospective, multicenter registry study involving 36 participating institutions in Japan. Patients with cardiac arrest who received ECPR were divided into two groups depending on whether or not they had received public assistance. The primary outcome was 30-day survival. Secondary outcomes were as follows: 30-day favorable neurological outcomes (cerebral performance category scores 1-2); survival at discharge; favorable neurological outcome at discharge; number of intensive care unit, hospital, ventilator, and extracorporeal membrane oxygenation days; medical expenses; proportion of percutaneous coronary intervention; target temperature management; mechanical circulatory support (MCS) device use; and withdrawal of life-sustaining therapy. Results: Of 2,157 patients registered in the SAVE-J II study, 1,885 patients were enrolled in this study; 99 patients (5.3%) received public assistance and 1,786 patients (94.7%) did not. Multivariable logistic regression analysis did not show a significant difference in 30-day survival (OR 1.22, 95% CI 0.77-1.95, p=0.40). The log-rank test for the Kaplan-Meiercurve on 30-day survival did not demonstrate a significant difference (p=0.46). Except for the use of MCS devices, there were no significant differences in secondary outcomes. Conclusions: The use of public assistance did not influence the prognoses of OHCA patients receiving ECPR. Treatment option during hospitalization may be affected by the use of public assistance.
Abstract Su607: Which would be major? witnessed collapse or bystander resuscitation?
Authors: Cheng Yi Fan, Chih-Wei Sung, Wen-Chu Chiang, CHIEN-HUA HUANG, Edward Pei-Chuan Huang
Journal: Circulation (2024)

Background: Witnessed collapse and bystander cardiopulmonary resuscitation (CPR) are two variables commonly used to predict outcomes in out-of-hospital cardiac arrest (OHCA). Some published studies have shown that bystander CPR were not significantly associated with outcomes after confounders adjusted. This may imply that witnessed collapse would be a superior prognostic factors beyond bystander CPR. Hypothesis: Witnessed collapse and bystander CPR may not contribute equally to prehospital return of spontaneous circulation (ROSC), and the former may be major. Aims: To investigate four prediction models for prehospital ROSC using stratification of the witnessed collapse and bystander CPR. Methods: The study enrolled OHCA patients treated by the emergency medical service (EMS) from January 2010 to December 2022 in three EMS systems in Taiwan. Data were extracted from the records of each medical service encounter, including patient demographics, dispatch timing, prehospital management, witnessed collapse and bystander CPR. The primary outcome was any prehospital ROSC. Patients were stratified into four groups by witnessed collapse (with/without) and bystander CPR (with/without) status, namely W+B+, W-B+, W+B- and W-B-. Prehospital ROSC prognostication were identified using multivariable logistic regression analysis. Results: The analysis comprised 17,323 patients, among whom 1,165 (6.7%) achieved prehospital ROSC. The W+B+ group demonstrated the highest prehospital ROSC rate at 13.0%, as compared with the other groups significantly (9.0%, 3.4%, and 4.1%, as depicted in Image 1). Stratification of the prehospital ROSC model (Image 2) indicated that the W+B+ group had several common predictors including age, traumatic arrest, no-flow time, public access defibrillation (PAD), and resuscitation events. However, certain predictors in other groups were removed during regression process. Notably, no-flow time significantly influenced prehospital ROSC only in the W+B+ and W+B- groups. Conversely, in the W-B- group, most variables had minimal impact on prehospital ROSC, reflecting the limited effectiveness of traditional predictors within this subgroup. Conclusion: The significance of witnessed collapse as a prognostic factor may be equal to or even greater than that of bystander CPR. Further studies are needed to confirm.
Abstract Su903: Prognostic Value of Early Grey-White Ratio in the presence of Hypercapnia after Cardiac Arrest
Authors: Nicholas Case, Patrick Coppler, Laura Faiver, Cecelia Ratay, Alexis Steinberg, Jonathan Tam, Aaron Weidman, Clifton Callaway, Jonathan Elmer
Journal: Circulation (2024)

Background: Cerebral edema following cardiac arrest can be quantified by measuring the ratio of grey matter to white matter radiodensity (GWR). Decreased GWR may reflect edema from irrecoverable neuronal cell death or reversible hyperemia driven by hypercapnia. We tested for an interaction between GWR and partial pressure of carbon dioxide (PCO2) predicting outcomes. Methods: We identified comatose post-arrest patients treated at our single center between 2010 and 2023 who underwent brain computed tomography (CT) imaging within 24 hours and PCO2 measured within one hour of CT. We extracted demographics, GWR, and PCO2 from our prospective registry and electronic health record. We scaled and centered data, then fit a multivariate logistic model to quantify the interaction between GWR and PCO2 in predicting survival. Results: Of 901 included patients, 356 (40%) were female, median [IQR] age was 61 [51-70], and 221 (25%) survived to discharge. CTs were obtained 4.18 [2.8-5.7] hours post-arrest. PCO2 was sampled within 36 median [24-47] minutes of CT. The median PCO2 was 47 [39-59] mmHg. GWR predicted survival (coefficient estimate 1.16, 95% confidence interval [CI], 0.91-1.44, p &lt; 0.001, but PCO2 (-0.11, 95% CI -0.32-0.09, p = 0.29) did not. There was no significant interaction between GWR and PCO2 (0.009, 95% CI -0.24-0.29, p = 0.95). Conclusion: There is no evidence of PCO2 modifying the association of early GWR with survival after resuscitation from cardiac arrest.
Abstract Su605: Return of Spontaneous Circulation after Transport with Ongoing Cardiopulmonary Resuscitation: Is Transport Always Futile?
Authors: Christopher Root, Chelsea White, Sasha Selby, Andrew Harrell, Benjamin Fisher, Darren Braude, Ryan Huebinger
Journal: Circulation (2024)

Introduction: Despite validated Termination of Resuscitation (TOR) rules for Out of Hospital Cardiac Arrest (OHCA) some OHCA patients are transported prior to Return of Spontaneous Circulation (ROSC), sometimes with long transport times. There are certain therapies unavailable in the prehospital setting which could make transport prior to ROSC beneficial for some OHCA patients. Hypothesis: We hypothesized that longer transport times for patients with ongoing Cardiopulmonary Resuscitation (CPR) would be associated with progressively lower probability of achieving ROSC. Aims: To determine if there is a transport time interval beyond which ROSC becomes so unlikely that transport time could be determinant factor for TOR. Methods: We performed a retrospective study of the 2020-2022 NEMSIS national prehospital dataset. We included adult OHCA patients that did not have ROSC prehospital, were transported to the hospital, and had outcome and timestamp data available. We calculated transport time for each encounter and stratified encounters into 5-minute transport time intervals. We defined our outcome as ROSC after transport. We used multivariable logistic regression evaluating the association between 5-minute increases in transport time and ROSC. We performed a secondary analysis of patients that met termination of resuscitation (TOR) criteria (unwitnessed OHCA with no CPR or AED placement prior to EMS arrival). Results: Of 1,409,692 OHCAs, we included 137,957 OHCAs that were transported without prehospital ROSC. The median transport time was 8.9 minutes (IQR 5.4-13.8), and 17,957 (13.1%) had ROSC after hospital arrival. In 5-minute intervals from 0-30 minutes, ROSC rates were 13.5%, 13.1%, 12.0%, 11.1%, 12.1%, and 13.9%. Odds of ROSC per 5-minute increase in transport time was 1.00 (95% CI 1.00-1.00). For patients that met field TOR criteria, rates of ROSC for each 5-minute interval from 0-30 minutes were 9.2%, 8.7%, 7.6%, 5.9%, 6.1%, 4.2%, 7.5%. Odds of ROSC per 5-minute increase in transport time was 0.93 (95% CI 0.88-0.98). Conclusion: In this dataset we were unable to identify a transport time interval up to 30 mins beyond which transport is futile, even in patients who were transported despite meeting the universal TOR rule. Decision to transport based on case-by-case OHCA characteristics could have influenced results. Further research is needed to identify the subset of patient in whom transport prior to ROSC may be beneficial.
Abstract Su602: Categorizing Witnessed Out-of-Hospital Cardiac Arrest by Bystander Type
Authors: Aditya Shekhar, Jacob Stebel, Avir Mitra, Joshua Kimbrell, Timothy Mader, Ethan Abbott
Journal: Circulation (2024)

Witnessed out-of-hospital cardiac arrests (OHCA) are associated with improved outcomes with increased likelihood of rapid activation of the emergency response system thus decreasing no-flow or low-flow times. Current literature has largely treated witnessed cardiac arrest as binary (i.e. was a cardiac arrest witnessed Yes/No). We hypothesize there is a need to further delineate and categorize distinct bystander types; these differences may have important downstream contributions to outcomes and survival and targets for improving training and recognition. For example, a bystander who is a healthcare provider with formal training or has experience performing resuscitation may be associated with better outcomes than a non-medical layperson. We examined a national-level database of emergency medical services (EMS) activations in the United States (NEMSIS). Inclusion criteria were any adult (18+ years) cardiac arrest activation between January 2022 and December 2023. Cardiac arrests taking place after EMS arrival (EMS-witnessed) were excluded. Witnessed status was described as unwitnessed, witnessed by healthcare provider, witnessed by family member, or witnessed by bystander. Across basic demographic variables, we compared overall witnessed rates, family member witnessed rates, and healthcare worker witnessed rates. A total of 791,217 cardiac arrests met inclusion criteria. Overall, 62.5% of arrests were unwitnessed, 22.8% were witnessed by a family member, and 6.3% were witnessed by a healthcare provider. Across sex, cardiac arrests in male patients were more likely to be witnessed, however, cardiac arrests in female patients were more likely to be witnessed by a family member or healthcare provider (p&lt;0.05). Significant differences in witnessed status were also seen across race/ethnicity. For instance, cardiac arrests in Black/African American patients were less likely to be witnessed by family members and cardiac arrests in Hispanic/Latino patients were less likely to be witnessed by healthcare workers (p&lt;0.05). Our analysis of a large and nationally-representative database of cardiac arrest suggests differences in rates of witnessed cardiac arrest and – perhaps, more importantly – the existence of different types of bystanders. Moreover, when considering these differences, there is heterogeneity among demographic variables. Future research is needed to understand whether these differences in bystander type may contribute to differences in outcomes.
Abstract Su604: Telecommunicator Guided Repositioning to the Floor During Out-of-Hospital Cardiac Arrest
Authors: Amanda Missel, Cameron Pinnock, Daniel Maironis, Deborah Rooney, Julia Tsutsui, Nicholas Wilson, Robert Neumar, Cynthia Bir
Journal: Circulation (2024)

Background: Current guidelines advise people to reposition a patient in need of cardiopulmonary resuscitation (CPR) to a firm surface. Repositioning is associated with longer time to first compression and a lower likelihood of bystander CPR. Older adults often have comorbidities that increase the risk for injury during repositioning. Aims: The aim of this research was to develop and evaluate the quality of a novel telecommunicator-CPR (TCPR) repositioning intervention. Methods: This study was conducted in two phases that employed a biomechanical surrogate containing head sensors. In Phase 1, our novel intervention was tested against three other TCPR scripts (A-general instructions, B-using sheet, C-pulling legs). Participants completed simulated 911 calls with all four scripts and were randomized to the order they completed them. The primary outcome was time to reposition, and the secondary outcome was risk for injury, determined by the head injury criterion (HIC). The novel intervention script (D) was revised based on feedback from participants and video review. In Phase 2, our revised TCPR intervention was tested against script A with participants randomized to either script received. The difference between groups’ time to reposition and risk for injury was determined using Kruskal-Wallis for Phase 1 and Wilcoxon Rank Sum for Phase 2. Results: Phase 1 had 35 participants, were 60% female with a mean (M) age of 45 years (19 SD) and 94% reported exercising weekly. One participant was unable to reposition the manikin to the floor using scripts A or B. Time to reposition was shortest for script C (M= 30 secs) and longest for novel script D (M= 99 secs, p&lt;.001, Table 1). Risk for injury was highest for script B, using the sheet, and lowest for novel script D, p=0.004. Phase 2 had 36 participants, were 56% were female with a mean age of 45 (18 SD). Time to reposition was shorter for script A, general instructions (p&lt;.001), and risk for injury was similarly very low in both scripts A and D (Table 1). Conclusions: Findings suggest use of a sheet or pulling on legs may increase the risk for injury and needs further study. General instructions, which allow the bystander to determine the best approach, had the shortest time to reposition while maintaining a low risk of injury. Our novel script resulted in the longest time to reposition but had a low risk of injury. Further study is warranted to test whether the time to deliver instructions could be shortened.