Abstract 254: High Shock Efficacy and Algorithm Performance for a 150J Biphasic Waveform AED Used by Lay and BLS Responders During Out-of-hospital Cardiac Arrest

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_4) ◽  
Author(s):  
Stacy Gehman ◽  
Edward Kompare ◽  
Barbara Fink ◽  
Tim Johnson ◽  
Walter Hufford ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Normal Sinus Rhythm ◽  
Convenience Sample ◽  
Shock Delivery ◽  
Shockable Rhythm ◽  
Normal Sinus ◽  
High Shock ◽  
Biphasic Waveform ◽  
Post Shock ◽  
Hospital Cardiac Arrest

Introduction: Effective AED defibrillation of out of hospital cardiac arrest (OHCA) depends on the safe and effective identification of shockable rhythms, and on delivery of effective defibrillation energy. This report summarizes rhythm detection performance and shock efficacy during OHCA uses of Philips HeartStart Home and OnSite AEDs using non-escalating 150 J therapy. Methods: A convenience sample of 185 OHCA AED patient uses were reviewed by clinical experts. All analysis periods that resulted in AED rhythm advisories (Shock Advised or No Shock Advised) were annotated. Shockable rhythm categories include VF and polymorphic VT/flutter. Non-Shockable rhythm categories include normal sinus rhythm, other rhythms (e.g., atrial fibrillation/flutter, bradycardia, SVT, idioventricular, bundle branch block), and asystole. Intermediate rhythms (benefits of defibrillation are limited or uncertain) were not included. Post-shock rhythm was categorized as shockable, non-shockable, or undeterminable (rhythms corrupted by CPR artifact or pads removal within 5-s of shock delivery). Shock success was defined as conversion to a non-shockable rhythm within 5-s post-shock. Results: A total of 487 analysis periods resulted in AED rhythm advisories, with 175 annotated as Shockable and 312 Non-shockable. Sensitivity and specificity (n/N, Exact 95% CI) were 97.7% (171/175, 94.3%, 99.4%) and 100% (312/312, 98.8%, 100.0%) respectively. A total of 165 shocks were delivered to 100 patients with 5 undeterminable post-shock rhythms. The remaining 160 shocks were delivered to 156 Shockable rhythm episodes. All shock efficacy was 96.9% (155/160, 92.9%, 99.0%): 150 episodes converted to non-shockable rhythms after one shock (96.2% (150/156, 91.8%, 98.6%)); 154 after two shocks (98.7% (154/156, 95.4%, 99.8%)); and 155 after three shocks, the first two of which were undeterminable (99.4% (155/156, 96.5%, 100.0%)). The remaining episode had a failed first shock, followed by an undeterminable second shock, which was the last shock of the use. Conclusion: For these 150J fixed-energy AEDs, OHCA defibrillation is safe (100% specificity), and effective (97.7% sensitivity; 96.2% single shock effectiveness; 98.7% after two shocks; 99.4% after three shocks).

Abstract 12258: Out-of-hospital Cardiac Arrest With Initially Shockable Rhythm: What Are the Outcomes if No Shock is Given?

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Yan Xiong ◽  
Ahamed H Idris
Keyword(s):  
Cardiac Arrest ◽  
Hospital Discharge ◽  
Spontaneous Circulation ◽  
Shock Delivery ◽  
Return Of Spontaneous Circulation ◽  
Shockable Rhythm ◽  
Multiple Variable ◽  
Multiple Variable Regression ◽  
Hospital Cardiac Arrest ◽  
Resuscitation Attempt

Background: Prompt defibrillation is critical for termination of ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) in out-of-hospital cardiac arrest (OHCA). For ethical reasons, the real impact of not shocking OHCA patients with a shockable rhythm is unlikely to be investigated in clinical trials and thus remains unknown. Objectives: To describe demographics, pre-hospital characteristics, interventions, and outcomes in OHCA patients with an initially shockable rhythm who did and did not get shocked in the field in DFW ROC site. Methods: We included all non-traumatic OHCA cases ≥18 years old with VF or VT as first known rhythms, who were treated and transported to a hospital within the DFW ROC site between 2006 - 2011. We report return of spontaneous circulation (ROSC) in the field and survival to hospital discharge for victims with and without shock delivered in the field. Multiple variable regression analysis assessed the association between shock delivery and ROSC in the field as well as survival. Results: Included were 882 adult non-traumatic OHCA cases with VF or VT as first known rhythms; mean (±SD) age was 60 ± 15 years, 71% male, bystander witnessed 56%, bystander resuscitation attempt 43%, public arrest location 26%, EMS response time 4.7 ± 2.3 min, 26.9% (237) had ROSC in the field, 14.9% (131) survived to hospital discharge; 93.4% (824) of all patients were shocked, while 6.6% (58) were not shocked. Of the 6.6% (58) who were not shocked, 12.1% (7) achieved ROSC in the field and 8.6% (5) survived to hospital discharge. For those not shocked in the field, the unadjusted and adjusted odds ratios for ROSC were 0.354 (95% CI 0.158-0.791, p=0.011) and 0.189 (95% CI 0.039-0.911, p=0.038), respectively; and for survival to hospital discharge they were 0.522 (95% CI 0.205-1.331, p=0.173) and 0.498 (95% CI 0.088-2.810, p=0.430), respectively. Conclusions: In the DFW ROC site, 6.6% of OHCA victims with an initially shockable rhythm did not receive a shock, which was significantly associated with decreased ROSC in the field. More patients survived who were shocked in the field, but this difference was not significant after adjustment for Utstein variables.

Abstract 128: Assessing the Temporal Trend in Survival to Hospital Admission Following Out-Of-Hospital Cardiac Arrest: Analysis From a Public Access Defibrillator Registry

Circulation ◽  
2019 ◽  
Vol 140 (Suppl_2) ◽  
Author(s):  
Hannah Torney ◽  
Olibhear McAlister ◽  
Adam Harvey ◽  
Raymond Bond ◽  
Dewar Finlay ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Hospital Admission ◽  
Time Of Day ◽  
Public Access ◽  
Patient Demographics ◽  
Shockable Rhythm ◽  
Post Shock ◽  
Day Of The Week ◽  
Get With The Guidelines ◽  
Hospital Cardiac Arrest

Introduction: The AHA Get With the Guidelines Resuscitation Investigators recently identified that in-hospital cardiac arrest patients admitted during nights and weekends are less likely to survive to discharge. Our analysis aimed to determine if a similar relationship applied to out-of-hospital cardiac arrest (OHCA) patients. Methods: Worldwide data collection began in Oct 2012. Users of HeartSine SAM PAD public access defibrillators submitted electronic event data (comprising time/date of event and electrocardiogram traces) and an event report form (comprising patient demographics, location of arrest and survival to hospital outcome). First shock success was defined as termination of shockable rhythm for 5 seconds post-shock. Data was analysed using R. Results: A total of 3400 OHCA cases were collected. Median (IQR) age was 63 (50, 75) and males accounted for 72.4% of the dataset. A total of 1127 first shocks were delivered, and first shock success was 87.2% (983 shocks). Survival outcomes were reported in 2942 cases, and 783 (26.6%) patients survived to hospital admission. First shock success as a response to day of the week (weekday versus weekend [12am Saturday-11.59pm Sunday]) adjusted for patient age, gender and location of arrest, was assessed and there was no association found. When the same model was fitted with survival to hospital admission as a response to day of the week, it was determined that patients are approximately 20% less likely to survive to hospital admission at the weekend (OR=0.81, 95%CI [0.68, 0.95], p=0.01). There was a negative association between survival and OHCA occurring at home (OR=0.32, 95%CI [0.10, 0.94], p=0.03) and increasing age (per 1-year increase, OR=0.99, 95%CI [0.98, 1.00], p<0.001). Adjusting the model for time of day (morning [6am-11.59am], afternoon [12pm-5.59pm], evening [6pm-11.59pm] and night [12am-5.59am]) did not highlight an association with any particular time of day. Conclusions: OHCA patients are significantly less likely to survive to hospital admission at weekends compared to weekdays. Further analysis on the availability of PADs at professional and recreational locations and availability of trained medical rescuers at the weekend versus weekdays could account for the differences observed.

Abstract 123: Field Accuracy of Paramedic Shock Delivery Using a Filtered ECG Rhythm

Circulation ◽  
2019 ◽  
Vol 140 (Suppl_2) ◽  
Author(s):  
Hill Stoecklein ◽  
Andrew Pugh ◽  
Michael Stroud ◽  
Scott Youngquist
Keyword(s):  
Cardiac Arrest ◽  
Salt Lake ◽  
Survival Rates ◽  
Salt Lake City ◽  
Fire Department ◽  
Shock Delivery ◽  
Shockable Rhythm ◽  
Lake City ◽  
Neurologically Intact ◽  
Hospital Cardiac Arrest

Introduction: Recognition and rapid defibrillation of shockable rhythms is strongly associated with increased survival from out-of-hospital cardiac arrest (OHCA). The Salt Lake City Fire Department (SLCFD) adopted ECG rhythm filtering technology in 2011, along with a protocol to rapidly defibrillate shockable rhythms without awaiting the end of the 2-minute CPR epoch. Paramedics were also trained to empirically shock asystole, as studies have shown poor agreement in cases of fine and moderate amplitude Ventricular Fibrillation (VF). Hypothesis: We hypothesized that the mandate to shock perceived asystole plus the use of filtering technology would result in high case sensitivity for shockable rhythms at the expense of an unknown frequency of shock delivery to organized rhythms. Methods: Prospectively collected defibrillator data from cardiac arrest cases treated by SLCFD between Dec 2011 and June 2019 were analyzed. Timing of rhythm changes and defibrillation events was manually abstracted using the manufacturer’s review software. The gold standard for rhythm interpretation was post-incident physician interpretation. Results: Paramedics attempted resuscitation in 942 OHCAs. We excluded 41 pediatric cases, 140 cases of BLS or bystander-only AED resuscitation, and 65 cases in which the defibrillator file was unavailable. Overall, 696 adult cardiac arrests with 1,389 shocks delivered were available for analysis. Shocks were delivered to 958 (69%) shockable, 261 (19%) asystole, 158 (11%) PEA, 4 (0.3%) SVT, and 8 (0.6%) unknown underlying rhythms. In 280 cases no shock was delivered despite an initial shockable rhythm in 3 of these cases. Shock delivery case sensitivity was 180/183 (0.98, 95% confidence interval [CI]:0.97-1.0) with false positive proportion of delivered shocks of 158/1,389 (0.11, 95% CI:0.10-0.13) for PEA only and 419/1,389 (0.30, 95% CI:0.28-0.33) for combined PEA and asystole. Neurologically intact (CPC 1-2) overall and Utstein survival rates were 15% and 46% respectively. Conclusions: Using ECG rhythm-filtering technology and an aggressive protocol to defibrillate VF and empirically shock asystole, we demonstrated high case sensitivity for VF at the expense of an 11% rate of shock delivery to underlying PEA.

scholarly journals Association of subsequent shock after conversion to shockable rhythm with outcomes stratified by the type of initial non-shockable rhythm in children with out-of-hospital cardiac arrest

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
Y Goto ◽  
A Funada ◽  
T Maeda ◽  
Y Goto
Keyword(s):  
Cardiac Arrest ◽  
Prognostic Significance ◽  
Cerebral Performance Category ◽  
Pulseless Electrical Activity ◽  
Delivery Time ◽  
Shock Delivery ◽  
Shockable Rhythm ◽  
Significant Difference ◽  
Neurologically Intact ◽  
Hospital Cardiac Arrest

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research) Background/Introduction: The rhythm conversion from initial non-shockable to shockable rhythm during cardiopulmonary resuscitation (CPR) by emergency medical services (EMS) providers may be associated with neurologically intact survival after out-of-hospital cardiac arrest (OHCA) in children with an initial non-shockable rhythm. However, the prognostic significance of rhythm conversion stratified by the type of initial non-shockable rhythm is still unclear. Purpose We aimed to investigate the association of subsequent shock after rhythm conversion to shockable rhythm with neurologically intact survival and shock delivery time (time from EMS-initiated CPR to first shock delivery) by the type of initial non-shockable rhythm in children with OHCA. Methods We analysed the records of 19,095 children (age &lt;18 years) with OHCA treated by EMS providers. Data were obtained from a prospectively recorded Japanese nationwide Utstein-style database for a 13-year period (2005–2017). The primary outcome measure was 1-month neurologically intact survival, defined as cerebral performance category score of 1 to 2. Patients were divided into the initial pulseless electrical activity (PEA) (n = 3,326 [17.4%]) and initial asystole (n = 15,769 [82.6%]) groups. Results The proportion of patients who received subsequent shock after conversion to shockable rhythm was significantly higher in the initial PEA than in the initial asystole groups (3.3% [109/3,326] vs. 1.4% [227/15,769], p &lt; 0.0001). The shock delivery time was significantly shorter in the initial PEA than in the initial asystole groups (median [IQR], 8 min [5 min – 12 min] vs. 10 min [6 min – 16 min], p &lt; 0.01). Among the initial PEA patients, there was no significant difference between subsequently shocked (10.0% [11/109]) and subsequently non-shocked patients (6.0% [192/3,217], p = 0.10) regarding the rate of 1-month neurologically intact survival. However, after adjusting for 9 pre-hospital variables, subsequent shock with a delivery time of &lt;10 min was associated with increased odds of neurologically intact survival compared with no shock delivery (adjusted odds ratio [OR], 2.45; 95% confidence interval [CI], 1.16–5.16], p = 0.018). Among the initial asystole patients, the rate of 1-month neurologically intact survival was significantly higher in the subsequently shocked (4.4% [10/227]) than in the subsequently non-shocked (0.7% [106/15,542], p &lt; 0.0001). A multivariate logistic regression model showed that subsequent shock with a delivery time of &lt;10 min was associated with increased odds of neurologically intact survival compared with no shock delivery (adjusted OR, 9.77 [95% CI, 4.2–22.5], p &lt; 0.0001). Conclusions In children with OHCA with an initial non-shockable rhythm, subsequent shock after conversion to shockable rhythm during CPR was associated with increased odds of 1-month neurologically intact survival only when shock was delivered &lt;10 min from EMS-initiated CPR regardless of the type of initial rhythm.

scholarly journals Outcomes of out-of-hospital cardiac arrest in Beijing: a 5-year cross-sectional study

BMJ Open ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. e041917
Author(s):  
Fei Shao ◽  
Haibin Li ◽  
Shengkui Ma ◽  
Dou Li ◽  
Chunsheng Li
Keyword(s):  
Cardiac Arrest ◽  
Urban Areas ◽  
Patient Characteristics ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
Term Survival ◽  
Shockable Rhythm ◽  
Bystander Cpr ◽  
Hospital Cardiac Arrest

ObjectiveThe purpose of this study was to assess the trends in outcomes of out-of-hospital cardiac arrest (OHCA) in Beijing over 5 years.DesignCross-sectional study.MethodsAdult patients with OHCA of all aetiologies who were treated by the Beijing emergency medical service (EMS) between January 2013 and December 2017 were analysed. Data were collected using the Utstein Style. Cases were followed up for 1 year. Descriptive statistics were used to characterise the sample and logistic regression was performed.ResultsOverall, 5016 patients with OHCA underwent attempted resuscitation by the EMS in urban areas of Beijing during the study period. Survival to hospital discharge was 1.2% in 2013 and 1.6% in 2017 (adjusted rate ratio=1.0, p for trend=0.60). Survival to admission and neurological outcome at discharge did not significantly improve from 2013 to 2017. Patient characteristics and the aetiology and location of cardiac arrest were consistent, but there was a decrease in the initial shockable rhythm (from 6.5% to 5.6%) over the 5 years. The rate of bystander cardiopulmonary resuscitation (CPR) increased steadily over the years (from 10.4% to 19.4%).ConclusionSurvival after OHCA in urban areas of Beijing did not improve significantly over 5 years, with long-term survival being unchanged, although the rate of bystander CPR increased steadily, which enhanced the outcomes of patients who underwent bystander CPR.

Abstract 16924: Initial AMSA and Increased AMSA After CPR Predict Second Shock Success in Initially Shock-resistant VF During Out-of-hospital Cardiac Arrest

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Ulrich Herken ◽  
Weilun Quan
Keyword(s):  
Logistic Regression ◽  
Cardiac Arrest ◽  
Ventricular Fibrillation ◽  
Success Rate ◽  
Fourier Transformation ◽  
Amplitude Spectrum ◽  
Fast Fourier Transformation ◽  
Shock Delivery ◽  
Spectrum Area ◽  
Hospital Cardiac Arrest

Purpose: Amplitude spectrum area (AMSA), which is calculated from the ventricular fibrillation (VF) waveform using fast Fourier transformation, has been recognized as a predictor of successful defibrillation (DF) and as an index of myocardial perfusion and viability during resuscitation. In this study, we investigated whether a change in AMSA occurring during CPR would predict DF outcome for subsequent DF attempts after a failed DF. We hypothesized that a patient responding to CPR with an increase in AMSA would have an increased likelihood of DF success. Methods: This was a retrospective analysis of out-of-hospital cardiac arrest patients who received a second DF due to initially shock-resistant VF. A total of 193 patients with an unsuccessful first DF were identified in a manufacturer database of electrocardiographic defibrillator records. AMSA was calculated for the first DF (AMSA1) and the second DF (AMSA2) during a 2.1 sec window ending 0.5 sec prior to DF. A successful DF attempt was defined as the presence of an organized rhythm with a rate ≥ 40 / min starting within 60 sec from the DF and lasting for > 30 sec. After the failed first DF, all patients received CPR for 2 to 3 minutes before delivery of the second DF. Change in AMSA (dAMSA) was calculated as dAMSA = AMSA2 - AMSA1. Results: The overall second DF success rate was 14.5%. Multivariable logistic regression showed that both AMSA1 and dAMSA were independent predictors of second DF success with odds ratios of 1.24 (95% CI 1.12 - 1.38, p<0.001) and 1.27 (95% CI 1.16 - 1.41, p<0.001) for each mVHz change in AMSA or dAMSA, respectively. Conclusions: In initially DF-resistant VF, a high initial AMSA value predicted an increased likelihood of second shock success. An increase of AMSA in response to CPR also predicted a higher second shock success rate. Monitoring of AMSA during resuscitation therefore may be useful to guide CPR efforts, possibly including timing of second shock delivery. These findings also further support the value of AMSA as indicator of myocardial viability.

Abstract 170: Challenges in Implementing an ECPR Program for Out of Hospital Cardiac Arrest

Circulation ◽  
2018 ◽  
Vol 138 (Suppl_2) ◽  
Author(s):  
Meshe Chonde ◽  
Jeremiah Escajeda ◽  
Jonathan Elmer ◽  
Frank X Guyette ◽  
Arthur Boujoukos ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Inclusion Criteria ◽  
Extracorporeal Cardiopulmonary Resuscitation ◽  
Implementation Challenges ◽  
Shockable Rhythm ◽  
Bystander Cpr ◽  
Stay And Play ◽  
Load And Go ◽  
Mechanical Cpr ◽  
Hospital Cardiac Arrest

Introduction: Extracorporeal cardiopulmonary resuscitation (ECPR) can treat cardiac arrest refractory to conventional therapy. Many institutions are interested in developing their own ECPR program. However, there are challenges in logistics and implementation. Hypothesis: Development of an ECPR team and identification of UPMC Presbyterian as a receiving center will increase recognition of potential ECPR candidates. Methods: We developed an infrastructure of Emergency Medical Services (EMS), Medic Command, and an in-hospital ECPR team. We identified inclusion criteria for patients with an out of hospital cardiac arrest (OHCA) likely to have a reversible arrest etiology and developed them into a simple checklist. These criteria were: witnessed arrest with bystander CPR, shockable rhythm, and ages 18 to 60. We trained local EMS crews to screen patients and review the checklist with a Command Physician prior to transport to our hospital. Results: From October 2015 to March 31 st 2018, there were 1165 dispatches for OHCA, of which 664 (57%) were treated and transported to the hospital and 120 to our institution. Of these, five patients underwent ECPR. Of the remaining cases, 64 (53%) had nonshockable rhythms, 48 (40%) were unwitnessed arrests, 50 (42%) were over age 60 and the remaining 20 (17%) had no documented reasons for exclusion. Prehospital CPR duration was 26 [IQR 25-40] min. Four patients (80%) underwent mechanical CPR with LUCAS device. Time from arrest to arrive on scene was 5 [IQR 4-6] min and time call MD command was 13 [IQR 7-21] min. Time to transport was 20 [IQR 19-21] min. Time from arrest to initiation of ECMO was 63 [IQR 59-69] min. Conclusions: ECPR is a relatively infrequent occurrence. Implementation challenges include prompt identification of patients with reversible OHCA causes, preferential transport to an ECPR capable facility and changing the focus of EMS in these select patients from a “stay and play” to a “load and go” mentality.

scholarly journals Emergency dispatch process and patient outcome in bystander-witnessed out-of-hospital cardiac arrest with a shockable rhythm

2015 ◽  
Vol 22 (4) ◽  
pp. 266-272 ◽  
Author(s):  
Pamela V.C. Hiltunen ◽  
Tom O. Silfvast ◽  
T. Helena Jäntti ◽  
Markku J. Kuisma ◽  
Jouni O. Kurola
Keyword(s):  
Patient Outcome ◽  
Cardiac Arrest ◽  
Shockable Rhythm ◽  
Hospital Cardiac Arrest

scholarly journals External validation of multimodal termination of resuscitation rules for out-of-hospital cardiac arrest patients in the COVID-19 era

2020 ◽  
Author(s):  
Haewon Jung ◽  
Mijin Lee ◽  
Jae Wan Cho ◽  
Sang Hun Lee ◽  
Suk Hee Lee ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Disease Transmission ◽  
Life Support ◽  
External Validation ◽  
Advanced Life Support ◽  
Survival Outcomes ◽  
Shock Delivery ◽  
Treatment Protocols ◽  
Multicenter Observational Study ◽  
Hospital Cardiac Arrest

Abstract Background: Futile resuscitation for out-of-hospital cardiac arrest (OHCA) patients in the coronavirus disease (COVID)-19 era can lead to risk of disease transmission and unnecessary transport. Various existing basic or advanced life support (BLS or ALS, respectively) rules for the termination of resuscitation (TOR) have been derived and validated in North America and Asian countries. This study aimed to evaluate the external validation of these rules in predicting the survival outcomes of OHCA patients in the COVID-19 era.Methods: This was a multicenter observational study using the WinCOVID-19 Daegu registry data collected during February 18–March 31, 2020. The subjects were patients who showed cardiac arrest of presumed cardiac etiology. The outcomes of each rule were compared to the actual patient survival outcomes. The sensitivity, specificity, false positive value (FPV), and positive predictive value (PPV) of each TOR rule were evaluated. Results: In total, 170 of the 184 OHCA patients were eligible and evaluated. TOR was recommended for 122 patients based on the international basic life support termination of resuscitation (BLS-TOR) rule, which showed 85% specificity, 74% sensitivity, 0.8% FPV, and 99% PPV for predicting unfavorable survival outcomes. When the traditional BLS-TOR rules and KoCARC TOR rule II were applied to our registry, one patient met the TOR criteria but survived at hospital discharge. With regard to the FPV (upper limit of 95% confidence interval <5%), specificity (100%), and PPV (>99%) criteria, only the KoCARC TOR rule I, which included a combination of three factors including not being witnessed by emergency medical technicians, presenting with an asystole at the scene, and not experiencing prehospital shock delivery or return of spontaneous circulation, was found to be superior to all other TOR rules. Conclusion: Among the previous nine BLS and ALS TOR rules, KoCARC TOR rule I was most suitable for predicting poor survival outcomes and showed improved diagnostic performance. Further research on variations in resources and treatment protocols among facilities, regions, and cultures will be useful in determining the feasibility of TOR rules for COVID-19 patients worldwide.

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