Elsevier

Resuscitation

Volume 117, August 2017, Pages 24-31
Resuscitation

Clinical paper
Prevalence, natural history, and time-dependent outcomes of a multi-center North American cohort of out-of-hospital cardiac arrest extracorporeal CPR candidates

https://doi.org/10.1016/j.resuscitation.2017.05.024Get rights and content

Abstract

Aim

Estimate prevalence of ECPR-eligible subjects in a large, North American, multi-center cohort, describe natural history with conventional resuscitation, and predict optimal timing of transition to ECPR.

Methods

Secondary analysis of clinical trial enrolling adults with non-traumatic OHCA. Primary outcome was survival to discharge with favorable outcome (mRS 0–3). Subjects were additionally classified as survival with unfavorable outcome (mRS 4–5), ROSC without survival (mRS 6), or without ROSC. We plotted subject accrual as a function of resuscitation duration (CPR onset to return of spontaneous circulation (ROSC) or termination of resuscitation), and estimated time-dependent probabilities of ROSC and mRS 0–3 at discharge. Adjusted logistic regression models tested the association between resuscitation duration and survival with mRS 0–3.

Results

Of 11,368 subjects, 1237 (10.9%; 95%CI 10.3–11.5%) were eligible for ECPR, Of these, 778 (63%) achieved ROSC, 466 (38%) survived to discharge, and 377 (30%) had mRS 0–3 at discharge. Half with eventual mRS 0–3 achieved ROSC within 8.8 min (95%CI 8.3–9.2 min) of resuscitation, and 90% within 21.0 min (95%CI 19.1–23.7 min). Time-dependent probabilities of ROSC and mRS 0–3 declined over elapsed resuscitation, and the likelihood of additional cases with mRS 0–3 beyond 20 min was 8.4% (95%CI 5.9–11.0%). Resuscitation duration was independently associated with survival to discharge with mRS 0–3 (OR 0.95; 95%CI 0.92–0.97).

Conclusion

Approximately 11% of subjects were eligible for ECPR. Only one-third survived to discharge with favorable outcome. Performing 9–21 min of conventional resuscitation captured most ECPR-eligible subjects with eventual mRS 0–3 at hospital discharge.

Introduction

Despite advances in care, rates of return of spontaneous circulation (ROSC) and functionally favorable survival after out-of-hospital cardiac arrest (OHCA) remain unacceptably poor [1]. Adding extracorporeal support to conventional cardiopulmonary resuscitation (ECPR) is an appealing method to improve outcomes after OHCA [2], [3], [4], [5], [6]. Compared to conventional resuscitation, ECPR improves blood flow and oxygen delivery during pulselessness, delays irreversible end-organ damage, and may facilitate therapies such as coronary angiography or fibrinolysis that treat the inciting cause of OHCA [7].

Whether these physiological benefits improve survival and functional recovery remains uncertain. While overall survival in published observational series is excellent [2], [3], [4], [5], [6], clinical features that make patients attractive candidates for ECPR (e.g. shockable initial cardiac rhythm, witnessed cardiac arrest, bystander CPR) are also associated with favorable clinical outcomes [8], [9], [10]. Reflecting the low level of existing evidence, current guidelines provide weak recommendation for consideration of ECPR in select cases [11]. The potential benefit, ideal patient selection, and optimal logistics to operationalize ECPR can only be tested in rigorous clinical trials.

To inform the design of such a trial, we estimated the prevalence of ECPR-eligible subjects using a large, multi-center cohort of EMS-treated OHCA, and described their baseline outcomes with conventional resuscitation. We additionally characterized the time-dependent effects of resuscitation duration on patient outcomes and clinical factors that would affect decisions to use ECPR in order to determine the optimal therapeutic window for conversion from traditional resuscitation to ECPR. Finally, we performed subgroup analyses to determine if this therapeutic window differed for subjects with shockable and nonshockable initial cardiac rhythms

Section snippets

Data source

We examined de-identified data from the Resuscitation Outcomes Consortium (ROC) Prehospital Resuscitation using an IMpedance valve and Early versus Delayed (PRIMED) trial [12], [13]. Data were obtained from National Institutes of Health Biologic Specimen and Data Repository Information Coordinating Center (BioLINCC). Michigan State University IRB granted waiver of consent for this secondary analysis of a de-identified dataset. The original trial found no difference in outcomes across all

Results

Among a 24 million total catchment population covering 35,000 square miles, the PRIMED dataset captured 17,445 subjects and 11,368 had complete time and outcome data (Fig. 1). Using our hypothetical criteria, 1237 subjects (10.9%; 95% CI 10.3–11.5%) were eligible for ECPR and included in the final cohort. Of these, 778/1237 (63%) achieved ROSC, 466/1237 (38%) survived to hospital discharge, and 377/1237 (30%) survived to hospital discharge with mRS 0–3. Median interval from EMS dispatch to

Discussion

Clinical decision-making surrounding ECPR is fraught with issues of candidate selection, timing, and logistical considerations. ECPR is a resource-intensive therapy that should be rationally deployed in such a way to maximize the potential benefit to patients while minimizing unnecessary exposure to complications and costs. We found that among consecutive EMS-treated OHCA subjects eligible for enrollment in the PRIMED clinical trial, 11% would have been eligible for ECPR using conservative

Conclusions

In a North American, multi-center cohort of EMS-treated OHCA subjects, approximately 11% met inclusion criteria for ECPR. One-third of ECPR eligible subjects failed to achieve ROSC with conventional resuscitation, and half of those with ROSC died in the hospital or were discharged with poor neurologic outcome. The likelihood of ROSC and neurologically favorable survival both steadily declined over elapsed resuscitation to approach zero, and resuscitation duration was independently associated

Conflicts of interest

Reynolds: Nothing to disclose.

Grunau: Nothing to disclose.

Elmer: Dr. Elmer is funded by NHLBI5K12HL109068.

Rittenberger: Dr. Rittenberger is funded through the AHA Grant-in-Aid program. He has received travel reimbursement and honoraria from C. R. Bard.

Sawyer: Nothing to disclose.

Singer: Nothing to disclose.

Proudfoot: Nothing to disclose.

Kurz: Dr. Kurz is funded by NIH5U01DK096037 (Site PI); K23AG038548 (Site PI); R01GM101197 (Site PI); R01GM103799 (Site PI); American Heart Association; Society

Acknowledgements

None

References (41)

  • N.J. Johnson et al.

    Extracorporeal life support as rescue strategy for out-of-hospital and emergency department cardiac arrest

    Resuscitation

    (2014)
  • L.W. Andersen et al.

    The relationship between age and outcome in out-of-hospital cardiac arrest patients

    Resuscitation

    (2015)
  • D. Zive et al.

    Resuscitation outcomes consortium investigators: variation in out-of-hospital cardiac arrest resuscitation and transport practices in the resuscitation outcomes consortium: ROC epistry-cardiac arrest

    Resuscitation

    (2011)
  • M. Poppe et al.

    The incidence of load&go out-of-hospital cardiac arrest candidates for emergency department utilization of emergency extracorporeal life support: a one-year review

    Resuscitation

    (2015)
  • J.T. Niemann

    Differences in cerebral and myocardial perfusion during closed-chest resuscitation

    Ann Emerg Med

    (1984)
  • N.A. Paradis et al.

    Aortic pressure during human cardiac arrest. Identification of pseudo-electromechanical dissociation

    Chest

    (1992)
  • A. Frisch et al.

    Documentation discrepancies of time-dependent critical events in out of hospital cardiac arrest

    Resuscitation

    (2014)
  • D. Writing Group Members Mozaffarian et al.

    American Heart Association statistics committee; stroke statistics subcommittee: heart disease and stroke statistics-2016 update: a report from the American Heart Association

    Circulation

    (2016)
  • S.J. Kim et al.

    An optimal transition time to extracorporeal cardiopulmonary resuscitation for predicting good neurological outcome in patients with out-of-hospital cardiac arrest: a propensity-matched study

    Crit Care

    (2014)
  • K. Maekawa et al.

    Extracorporeal cardiopulmonary resuscitation for patients with out-of-hospital cardiac arrest of cardiac origin: a propensity-matched study and predictor analysis

    Crit Care Med

    (2013)
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    A Spanish translated version of the abstract of this article appears as Appendix in the final online version at http://dx.doi.org/10.1016/j.resuscitation.2017.05.024.

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