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Dive into the research topics where Heather Herren is active.

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Featured researches published by Heather Herren.


Resuscitation | 2016

Association of early withdrawal of life-sustaining therapy for perceived neurological prognosis with mortality after cardiac arrest

Jonathan Elmer; Cesar Torres; Tom P. Aufderheide; Michael A. Austin; Clifton W. Callaway; Eyal Golan; Heather Herren; Jamie Jasti; Peter J. Kudenchuk; Damon C. Scales; Dion Stub; Derek Richardson; Dana Zive

BACKGROUND Withdrawing life-sustaining therapy because of perceived poor neurological prognosis (WLST-N) is a common cause of hospital death after out-of-hospital cardiac arrest (OHCA). Although current guidelines recommend against WLST-N before 72h (WLST-N<72), this practice is common and may increase mortality. We sought to quantify these effects. METHODS In a secondary analysis of a multicenter OHCA trial, we evaluated survival to hospital discharge and survival with favorable functional status (modified Rankin Score ≤3) in adults alive >1h after hospital admission. Propensity score modeling the probability of exposure to WLST-N<72 based on pre-exposure covariates was used to match unexposed subjects with those exposed to WLST-N<72. We determined the probability of survival and functionally favorable survival in the unexposed matched cohort, fit adjusted logistic regression models to predict outcomes in this group, and then used these models to predict outcomes in the exposed cohort. Combining these findings with current epidemiologic statistics we estimated mortality nationally that is associated with WLST-N<72. RESULTS Of 16,875 OHCA subjects, 4265 (25%) met inclusion criteria. WLST-N<72 occurred in one-third of subjects who died in-hospital. Adjusted analyses predicted that exposed subjects would have 26% survival and 16% functionally favorable survival if WLST-N<72 did not occur. Extrapolated nationally, WLST-N<72 may be associated with mortality in approximately 2300 Americans each year of whom nearly 1500 (64%) might have had functional recovery. CONCLUSIONS After OHCA, death following WLST-N<72 may be common and is potentially avoidable. Reducing WLST-N<72 has national public health implications and may afford an opportunity to decrease mortality after OHCA.


Resuscitation | 2015

A quantitative analysis of out-of-hospital pediatric and adolescent resuscitation quality – A report from the ROC epistry-cardiac arrest☆

Robert M. Sutton; Erin Case; Siobhan P. Brown; Dianne L. Atkins; Vinay Nadkarni; Jonathan R. Kaltman; Clifton W. Callaway; Ahamed H. Idris; Graham Nichol; Jamie Hutchison; Ian R. Drennan; Michael A. Austin; Mohamud Daya; Sheldon Cheskes; Jack Nuttall; Heather Herren; James Christenson; Douglas L. Andrusiek; Christian Vaillancourt; James J. Menegazzi; Thomas D. Rea; Robert A. Berg

AIM High-quality cardiopulmonary resuscitation (CPR) may improve survival. The quality of CPR performed during pediatric out-of-hospital cardiac arrest (p-OHCA) is largely unknown. The main objective of this study was to describe the quality of CPR performed during p-OHCA resuscitation attempts. METHODS Prospective observational multi-center cohort study of p-OHCA patients ≥ 1 and < 19 years of age registered in the Resuscitation Outcomes Consortium (ROC) Epistry database. The primary outcome was an a priori composite variable of compliance with American Heart Association (AHA) guidelines for both chest compression (CC) rate and CC fraction (CCF). Event compliance was defined as a case with 60% or more of its minute epochs compliant with AHA targets (rate 100-120 min(-1); depth ≥ 38 mm; and CCF ≥ 0.80). In a secondary analysis, multivariable logistic regression was used to evaluate the association between guideline compliance and return of spontaneous circulation (ROSC). RESULTS Between December 2005 and December 2012, 2564 pediatric events were treated by EMS providers, 390 of which were included in the final cohort. Of these events, 22% achieved AHA compliance for both rate and CCF, 36% for rate alone, 53% for CCF alone, and 58% for depth alone. Over time, there was a significant increase in CCF (p < 0.001) and depth (p = 0.03). After controlling for potential confounders, there was no significant association between AHA guideline compliance and ROSC. CONCLUSIONS In this multi-center study, we have established that there are opportunities for professional rescuers to improve prehospital CPR quality. Encouragingly, CCF and depth both increased significantly over time.


Resuscitation | 2016

Design and implementation of the Resuscitation Outcomes Consortium Pragmatic Airway Resuscitation Trial (PART)

Henry E. Wang; David K. Prince; Shannon Stephens; Heather Herren; Mohamud Daya; Neal Richmond; Jestin N. Carlson; Craig R. Warden; M. Riccardo Colella; Ashley Brienza; Tom P. Aufderheide; Ahamed H. Idris; Robert H. Schmicker; Susanne May; Graham Nichol

Airway management is an important component of resuscitation from out-of-hospital cardiac arrest (OHCA). The optimal approach to advanced airway management is unknown. The Pragmatic Airway Resuscitation Trial (PART) will compare the effectiveness of endotracheal intubation (ETI) and Laryngeal Tube (LT) insertion upon 72-h survival in adult OHCA. Encompassing United States Emergency Medical Services agencies affiliated with the Resuscitation Outcomes Consortium (ROC), PART will use a cluster-crossover randomized design. Participating subjects will include adult, non-traumatic OHCA requiring bag-valve-mask ventilation. Trial interventions will include (1) initial airway management with ETI and (2) initial airway management with LT. The primary and secondary trial outcomes are 72-h survival and return of spontaneous circulation. Additional clinical outcomes will include airway management process and adverse events. The trial will enroll a total of 3000 subjects. Results of PART may guide the selection of advanced airway management strategies in OHCA.


Resuscitation | 2016

Unchanged pediatric out-of-hospital cardiac arrest incidence and survival rates with regional variation in North America

Ericka L. Fink; David K. Prince; Jonathan R. Kaltman; Dianne L. Atkins; Michael A. Austin; Craig R. Warden; Jamie Hutchison; Mohamud Daya; Scott A. Goldberg; Heather Herren; Janice A. Tijssen; James Christenson; Christian Vaillancourt; Ronna G. Miller; Robert H. Schmicker; Clifton W. Callaway

AIM Outcomes for pediatric out-of-hospital cardiac arrest (OHCA) are poor. Our objective was to determine temporal trends in incidence and mortality for pediatric OHCA. METHODS Adjusted incidence and hospital mortality rates of pediatric non-traumatic OHCA patients from 2007-2012 were analyzed using the 9 region Resuscitation Outcomes Consortium-Epidemiological Registry (ROC-Epistry) database. Children were divided into 4 age groups: perinatal (<3 days), infants (3days-1year), children (1-11 years), and adolescents (12-19 years). ROC regions were analyzed post-hoc. RESULTS We studied 1738 children with OHCA. The age- and sex-adjusted incidence rate of OHCA was 8.3 per 100,000 person-years (75.3 for infants vs. 3.7 for children and 6.3 for adolescents, per 100,000 person-years, p<0.001). Incidence rates differed by year (p<0.001) without overall linear trend. Annual survival rates ranged from 6.7-10.2%. Survival was highest in the perinatal (25%) and adolescent (17.3%) groups. Stratified by age group, survival rates over time were unchanged (all p>0.05) but there was a non-significant linear trend (1.3% increase) in infants. In the multivariable logistic regression analysis, infants, unwitnessed event, initial rhythm of asystole, and region were associated with worse survival, all p<0.001. Survival by region ranged from 2.6-14.7%. Regions with the highest survival had more cases of EMS-witnessed OHCA, bystander CPR, and increased EMS-defibrillation (all p<0.05). CONCLUSIONS Overall incidence and survival of children with OHCA in ROC regions did not significantly change over a recent 5year period. Regional variation represents an opportunity for further study to improve outcomes.


JAMA Cardiology | 2017

Association of Neighborhood Demographics With Out-of-Hospital Cardiac Arrest Treatment and Outcomes: Where You Live May Matter

Monique A. Starks; Robert H. Schmicker; Eric D. Peterson; Susanne May; Jason E. Buick; Peter J. Kudenchuk; Ian R. Drennan; Heather Herren; Jamie Jasti; Michael R. Sayre; Dion Stub; Gary M. Vilke; Shannon Stephens; Anna Marie Chang; Jack Nuttall; Graham Nichol

Importance We examined whether resuscitation care and outcomes vary by the racial composition of the neighborhood where out-of-hospital cardiac arrests (OHCAs) occur. Objective To evaluate the association between bystander treatments (cardiopulmonary resuscitation and automatic external defibrillation) and timing of emergency medical services personnel on OHCA outcomes according to the racial composition of the neighborhood where the OHCA event occurred. Design, Setting, and Participants This retrospective observational cohort study examined patients with OHCA from January 1, 2008, to December 31, 2011, using data from the Resuscitation Outcomes Consortium. Neighborhoods where OHCA occurred were classified by census tract, based on percentage of black residents: less than 25%, 25% to 50%, 51% to 75%, or more than 75%. Multilevel mixed-effects logistic regression modeling examined the association between racial composition of neighborhoods and OHCA survival, adjusting for patient, neighborhood, and treatment characteristics. Main Outcomes and Measures Survival to discharge, return of spontaneous circulation on emergency department arrival, and favorable neurologic status at discharge. Results We examined 22 816 adult patients with nontraumatic OHCA at Resuscitation Outcomes Consortium sites in the United States. The median age of patients with OHCA was 64 years (interquartile range [IQR], 51-78). Compared with patients who experienced OHCA in neighborhoods with a lower proportion of black residents, those in neighborhoods with more than 75% black residents were slightly younger, were more frequently women, had lower rates of initial shockable rhythm, and less frequently experienced OHCA in a public location. The percentage of patients with OHCA receiving bystander cardiopulmonary resuscitation or a lay automatic external defibrillation was inversely associated with the percentage of black residents in neighborhoods. Compared with OHCA in predominantly white neighborhoods (<25% black), those with OHCA in mixed to majority black neighborhoods had lower adjusted survival rates to hospital discharge (25%-50% black: odds ratio, 0.76; 95% CI, 0.61-0.93; 51%-75% black: odds ratio, 0.67; 95% CI, 0.49-0.90; >75% black: odds ratio, 0.63; 95% CI, 0.50-0.79; P < .001). There was similar mortality risk for black and white patients with OHCA in each neighborhood racial quantile. When the primary model included geographic site, there was an attenuated nonsignificant association between racial composition in a neighborhood and survival. Conclusions and Relevance Those with OHCA in predominantly black neighborhoods had the lowest rates of bystander cardiopulmonary resuscitation and automatic external defibrillation use and significantly lower likelihood for survival compared with predominantly white neighborhoods. Improving bystander treatments in these neighborhoods may improve cardiac arrest survival.


Resuscitation | 2017

A comparison of the universal TOR Guideline to the absence of prehospital ROSC and duration of resuscitation in predicting futility from out-of-hospital cardiac arrest ☆

Ian R. Drennan; Erin Case; P. Richard Verbeek; Joshua C. Reynolds; Zachary D. Goldberger; Jamie Jasti; Mark Charleston; Heather Herren; Ahamed H. Idris; Paul R. Leslie; Michael A. Austin; Yan Xiong; Robert H. Schmicker; Laurie J. Morrison

INTRODUCTION The Universal Termination of Resuscitation (TOR) Guideline accurately identifies potential out-of-hospital cardiac arrest (OHCA) survivors. However, implementation is inconsistent with some Emergency Medical Service (EMS) agencies using absence of return of spontaneous circulation (ROSC) as sole criterion for termination. OBJECTIVE To compare the performance of the Universal TOR Guideline with the single criterion of no prehospital ROSC. Second, to determine factors associated with survival for patients transported without a ROSC. Lastly, to compare the impact of time to ROSC as a marker of futility to the Universal TOR Guideline. DESIGN Retrospective, observational cohort study. PARTICIPANTS Non-traumatic, adult (≥18 years) OHCA patients of presumed cardiac etiology treated by EMS providers. SETTING ROC-PRIMED and ROC-Epistry post ROC-PRIMED databases between 2007 and 2011. OUTCOMES Primary outcome was survival to hospital discharge and the secondary outcome was functional survival. We used multivariable regression to evaluate factors associated with survival in patients transported without a ROSC. RESULTS 36,543 treated OHCAs occurred of which 9467 (26%) were transported to hospital without a ROSC. Patients transported without a ROSC who met the Universal TOR Guideline for transport had a survival of 3.0% (95% CI 2.5-3.4%) compared to 0.7% (95% CI 0.4-0.9%) in patients who met the Universal TOR Guideline for termination. The Universal TOR Guideline identified 99% of survivors requiring continued resuscitation and transportation to hospital including early identification of survivors who sustained a ROSC after extended durations of CPR. CONCLUSION Using absence of ROSC as a sole predictor of futility misses potential survivors. The Universal TOR Guideline remains a strong predictor of survival.


JAMA | 2018

Effect of a Strategy of Initial Laryngeal Tube Insertion vs Endotracheal Intubation on 72-Hour Survival in Adults With Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial

Henry E. Wang; Robert H. Schmicker; Mohamud Daya; Shannon Stephens; Ahamed H. Idris; Jestin N. Carlson; M. Riccardo Colella; Heather Herren; Matthew Hansen; Neal Richmond; Juan Carlos Puyana; Tom P. Aufderheide; Randal Gray; Pamela C. Gray; Mike Verkest; Pamela Owens; Ashley Brienza; Kenneth Sternig; Susanne J. May; George Sopko; Myron L. Weisfeldt; Graham Nichol

Importance Emergency medical services (EMS) commonly perform endotracheal intubation (ETI) or insertion of supraglottic airways, such as the laryngeal tube (LT), on patients with out-of-hospital cardiac arrest (OHCA). The optimal method for OHCA advanced airway management is unknown. Objective To compare the effectiveness of a strategy of initial LT insertion vs initial ETI in adults with OHCA. Design, Setting, and Participants Multicenter pragmatic cluster-crossover clinical trial involving EMS agencies from the Resuscitation Outcomes Consortium. The trial included 3004 adults with OHCA and anticipated need for advanced airway management who were enrolled from December 1, 2015, to November 4, 2017. The final date of follow-up was November 10, 2017. Interventions Twenty-seven EMS agencies were randomized in 13 clusters to initial airway management strategy with LT (n = 1505 patients) or ETI (n = 1499 patients), with crossover to the alternate strategy at 3- to 5-month intervals. Main Outcomes and Measures The primary outcome was 72-hour survival. Secondary outcomes included return of spontaneous circulation, survival to hospital discharge, favorable neurological status at hospital discharge (Modified Rankin Scale score ⩽3), and key adverse events. Results Among 3004 enrolled patients (median [interquartile range] age, 64 [53-76] years, 1829 [60.9%] men), 3000 were included in the primary analysis. Rates of initial airway success were 90.3% with LT and 51.6% with ETI. Seventy-two hour survival was 18.3% in the LT group vs 15.4% in the ETI group (adjusted difference, 2.9% [95% CI, 0.2%-5.6%]; P = .04). Secondary outcomes in the LT group vs ETI group were return of spontaneous circulation (27.9% vs 24.3%; adjusted difference, 3.6% [95% CI, 0.3%-6.8%]; P = .03); hospital survival (10.8% vs 8.1%; adjusted difference, 2.7% [95% CI, 0.6%-4.8%]; P = .01); and favorable neurological status at discharge (7.1% vs 5.0%; adjusted difference, 2.1% [95% CI, 0.3%-3.8%]; P = .02). There were no significant differences in oropharyngeal or hypopharyngeal injury (0.2% vs 0.3%), airway swelling (1.1% vs 1.0%), or pneumonia or pneumonitis (26.1% vs 22.3%). Conclusions and Relevance Among adults with OHCA, a strategy of initial LT insertion was associated with significantly greater 72-hour survival compared with a strategy of initial ETI. These findings suggest that LT insertion may be considered as an initial airway management strategy in patients with OHCA, but limitations of the pragmatic design, practice setting, and ETI performance characteristics suggest that further research is warranted. Trial Registration ClinicalTrials.gov Identifier: NCT02419573


Circulation | 2018

Time to Epinephrine Administration and Survival From Nonshockable Out-of-Hospital Cardiac Arrest Among Children and Adults

Matthew Hansen; Robert H. Schmicker; Craig D. Newgard; Brian Grunau; Frank X. Scheuermeyer; Sheldon Cheskes; Veer Vithalani; Fuad Alnaji; Thomas D. Rea; Ahamed H. Idris; Heather Herren; Jamie Hutchison; Mike Austin; Debra Egan; Mohamud Daya

Background: Previous studies have demonstrated that earlier epinephrine administration is associated with improved survival from out-of-hospital cardiac arrest (OHCA) with shockable initial rhythms. However, the effect of epinephrine timing on patients with nonshockable initial rhythms is unclear. The objective of this study was to measure the association between time to epinephrine administration and survival in adults and children with emergency medical services (EMS)–treated OHCA with nonshockable initial rhythms. Methods: We performed a secondary analysis of OHCAs prospectively identified by the Resuscitation Outcomes Consortium network from June 4, 2011, to June 30, 2015. We included patients of all ages with an EMS-treated OHCA and an initial nonshockable rhythm. We excluded those with return of spontaneous circulation in <10 minutes. We conducted a subgroup analysis involving patients <18 years of age. The primary exposure was time (minutes) from arrival of the first EMS agency to the first dose of epinephrine. Secondary exposure was time to epinephrine dichotomized as early (<10 minutes) or late (≥10 minutes). The primary outcome was survival to hospital discharge. We adjusted for Utstein covariates and Resuscitation Outcomes Consortium study site. Results: From 55 568 EMS-treated OHCAs, 32 101 patients with initial nonshockable rhythms were included. There were 12 238 in the early group, 14 517 in the late group, and 5346 not treated with epinephrine. After adjusting for potential confounders, each minute from EMS arrival to epinephrine administration was associated with a 4% decrease in odds of survival for adults, odds ratio=0.96 (95% confidence interval, 0.95–0.98). A subgroup analysis (n=13 290) examining neurological outcomes showed a similar association (adjusted odds ratio, 0.94 per minute; 95% confidence interval, 0.89–0.98). When epinephrine was given late in comparison with early, odds of survival were 18% lower (odds ratio, 0.82; 95% confidence interval, 0.68–0.98). In a pediatric analysis (n=595), odds of survival were 9% lower (odds ratio, 0.91; 95% confidence interval, 0.81–1.01) for each minute delay in epinephrine. Conclusions: Among OHCAs with nonshockable initial rhythms, the majority of patients were administered epinephrine >10 minutes after EMS arrival. Each minute delay in epinephrine administration was associated with decreased survival and unfavorable neurological outcomes. EMS agencies should consider strategies to reduce epinephrine administration times in patients with initial nonshockable rhythms.


Resuscitation | 2017

The association between AHA CPR quality guideline compliance and clinical outcomes from out-of-hospital cardiac arrest

Sheldon Cheskes; Robert H. Schmicker; Thomas D. Rea; Laurie J. Morrison; Brian Grunau; Ian R. Drennan; Brian G. Leroux; Christian Vaillancourt; Terri A. Schmidt; Allison C. Koller; Peter J. Kudenchuk; Tom P. Aufderheide; Heather Herren; Katharyn Flickinger; Mark Charleston; Ron Straight; Jim Christenson

BACKGROUND Measures of chest compression fraction (CCF), compression rate, compression depth and pre-shock pause have all been independently associated with improved outcomes from out-of-hospital (OHCA) cardiac arrest. However, it is unknown whether compliance with American Heart Association (AHA) guidelines incorporating all the aforementioned metrics, is associated with improved survival from OHCA. METHODS We performed a secondary analysis of prospectively collected data from the Resuscitation Outcomes Consortium Epistry-Cardiac Arrest database. As per the 2015 American Heart Association (AHA) guidelines, guideline compliant cardiopulmonary resuscitation (CPR) was defined as CCF >0.8, chest compression rate 100-120/minute, chest compression depth 50-60mm, and pre-shock pause <10s. Multivariable logistic regression models controlling for Utstein variables were used to assess the relationship between global guideline compliance and survival to hospital discharge and neurologically intact survival with MRS ≤3. Due to potential confounding between CPR quality metrics and cases that achieved early ROSC, we performed an a priori subgroup analysis restricted to patients who obtained ROSC after ≥10min of EMS resuscitation. RESULTS After allowing for study exclusions, 19,568 defibrillator records were collected over a 4-year period ending in June 2015. For all reported models, the reference standard included all cases who did not meet all CPR quality benchmarks. For the primary model (CCF, rate, depth), there was no significant difference in survival for resuscitations that met all CPR quality benchmarks (guideline compliant) compared to the reference standard (OR 1.26; 95% CI: 0.80, 1.97). When the dataset was restricted to patients obtaining ROSC after ≥10min of EMS resuscitation (n=4,158), survival was significantly higher for those resuscitations that were guideline compliant (OR 2.17; 95% CI: 1.11, 4.27) compared to the reference standard. Similar findings were obtained for neurologically intact survival with MRS ≤3 (OR 3.03; 95% CI: 1.12, 8.20). CONCLUSIONS In this observational study, compliance with AHA guidelines for CPR quality was not associated with improved outcomes from OHCA. Conversely, when restricting the cohort to those with late ROSC, compliance with guidelines was associated with improved clinical outcomes. Strategies to improve overall guideline compliance may have a significant impact on outcomes from OHCA.


Resuscitation | 2017

Compression-to-ventilation ratio and incidence of rearrest—A secondary analysis of the ROC CCC trial☆

David D. Salcido; Robert H. Schmicker; Jason E. Buick; Sheldon Cheskes; Brian Grunau; Peter J. Kudenchuk; Brian G. Leroux; Stephanie Zellner; Dana Zive; Tom P. Aufderheide; Allison C. Koller; Heather Herren; Jack Nuttall; Matthew L. Sundermann; James J. Menegazzi

BACKGROUND Previous work has demonstrated that when out-of-hospital cardiac arrest (OHCA) patients achieve return of spontaneous circulation (ROSC), but subsequently have another cardiac arrest prior to hospital arrival (rearrest), the probability of survival to hospital discharge is significantly decreased. Additionally, few modifiable factors for rearrest are known. We sought to examine the association between rearrest and compression-to-ventilation ratio during cardiopulmonary resuscitation (CPR) and to confirm the association between rearrest and outcomes. HYPOTHESIS Rearrest incidence would be similar between cases treated with 30:2 or continuous chest compression (CCC) CPR, but inversely related to survival and good neurological outcome. METHODS We conducted a secondary analysis of a large randomized-controlled trial of CCC versus 30:2 CPR for the treatment of OHCA between 2011 and 2015 among 8 sites of the Resuscitation OUTCOMES: Consortium (ROC). Patients were randomized through an emergency medical services (EMS) agency-level cluster randomization design to receive either 30:2 or CCC CPR. Case data were derived from prehospital patient care reports, digital defibrillator files, and hospital records. The primary analysis was an as-treated comparison of the proportion of patients with a rearrest for patients who received 30:2 versus those who received CCC. In addition, we assessed the association between rearrest and both survival to hospital discharge and favorable neurological outcome (Modified Rankin Score≤3) in patients with and without ROSC upon ED arrival using multivariable logistic regression adjusting for age, sex, initial rhythm and measures of CPR quality. RESULTS There were 14,109 analyzable cases that were determined to have definitively received either CCC or 30:2 CPR. Of these, 4713 had prehospital ROSC and 2040 (43.2%) had at least one rearrest. Incidence of rearrest was not significantly different between patients receiving CCC and 30:2 (44.1% vs 41.8%; adjusted OR: 1.01; 95% CI: 0.88, 1.16). Rearrest was significantly associated with lower survival (23.3% vs 36.9%; adjusted OR: 0.46; 95%CI: 0.36-0.51) and worse neurological outcome (19.4% vs 30.2%; adjusted OR: 0.46; 95%CI: 0.38, 0.55). CONCLUSION Rearrest occurrence was not significantly different between patients receiving CCC and 30:2, and was inversely associated with survival to hospital discharge and MRS.

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Tom P. Aufderheide

Medical College of Wisconsin

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Ahamed H. Idris

University of Texas Southwestern Medical Center

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Jamie Jasti

Medical College of Wisconsin

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Brian Grunau

University of British Columbia

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