Rapid Response VA-ECMO in Refractory Out-of-hospital Cardiac Arrest

A selected group of patients with refractory cardiac arrest may benefit from inhospital treatment and this may warrant transfer to the hospital with ongoing CPR. In patients with VF or ventricular tachycardia (VT) the underlying cause may be reversible and damage to other organs is limited at the time of the arrest. Many patients will have a coronary event that can be treated by angioplasty. However, up to now absence of ROSC poses a barrier for angioplasty, and most patients are therefore not even transported to a hospital. With the use of extra corporeal membrane oxygenation (ECMO) the circulation can be restored immediately, providing time to diagnose and treat the underlying cause of the cardiac arrest. International cohort studies show that a strategy of pre-hospital triage and transport to a cardiac arrest expertise center for "rapid-response" ECMO and coronary revascularization is feasible and improves survival.

A clinical pathway will encompass intense cooperation and optimal logistics between several paramedical and medical disciplines, i.e. from prehospital ambulance service to intensive care. Incorporation of mechanical chest compressions devices (LUCAS™), rapid-response veno-arterial (VA-)ECMO (Cardiohelp, Maquet), and ECMO assisted revascularization in a dedicated clinical pathway will offer a potential lifesaving treatment option that is in accordance with the recommendations in the current Guidelines.

The aim of the study is to investigate the feasibility of a new local clinical pathway in our hospital to provide ECPR for refractory OHCA patients.

Coronary heart disease is the leading cause of cardiac arrest. The incidence of cardiac arrest in Europe is between 0.4 and 1 per 1000 inhabitants per year, thus involving between 350.000 and 700.000 people per year. Approximately, 275.000 of these cardiac arrests are treated by the emergency medical service (EMS) in Europe. (1) Survival after cardiac arrest varies from less than 5% to 60% according to the characteristics of the cardiac arrest event (e.g. cardiac etiology, witnessed arrest, initial recorded rhythm (shockable: ventricular fibrillation (VF), ventricular tachycardia (VT) or not shockable).(1) Cardiac arrest patients, who despite conventional cardiopulmonary resuscitation (CPR) do not achieve return of spontaneous circulation (ROSC) within 10-20 minutes of advanced life support (ALS) have the worst prognosis with rates of survival to hospital discharge of 2-11%.

A selected group of patients with refractory cardiac arrest may benefit from very aggressive in-hospital treatment and this may warrant transfer to the hospital with ongoing CPR. In patients with VF or ventricular tachycardia (VT) the underlying cause may be reversible and damage to other organs is limited at the time of the arrest. Many patients will have a coronary event that can be treated by angioplasty. However, up to now absence of ROSC poses a barrier for angioplasty, and most patients are therefore not even transported to a hospital.

With the use of extra corporeal membrane oxygenation (ECMO) the circulation can be restored immediately, providing time to diagnose and treat the underlying cause of the cardiac arrest. International cohort studies show that a strategy of pre-hospital triage and transport to a cardiac arrest expertise center for "rapid-response" ECMO and coronary revascularization is feasible and improves survival. The recent 2015 European Resuscitation Council Guidelines for Resuscitation position extracorporeal CPR (ECPR) as follows: "ECPR should be considered as a rescue therapy for those patients in whom initial advanced life support (ALS) measures are unsuccessful and to facilitate specific interventions (e.g. coronary angiography and percutaneous coronary intervention (PCI) or pulmonary thrombectomy for massive pulmonary embolism)".(2) A recent meta-analysis performed by our group supports ECMO in this setting. (3)

Currently, a strong pre-hospital and clinical pathway for acute myocardial infarction exists in the greater Amsterdam region / Noord-Holland region, i.e. "Lifenet protocol". The Academic Medical Center is an international recognized center with the ARREST program to evaluate treatments for out-of-hospital cardiac arrest (OHCA).(4) However, a dedicated clinical pathway for refractory OHCA patients does not yet exist. Integration of the "Lifenet protocol" and ARREST program would provide an ideal setting to create and install a dedicated clinical pathway for these cardiac arrest patients.

The existing clinical pathway for cardiac arrest patients will be optimized and upgraded to be able to provide ECPR for refractory cardiac arrest patients. This clinical pathway will encompass intense cooperation and optimal logistics between several paramedical and medical disciplines, i.e. from pre-hospital ambulance service to intensive care. Incorporation of mechanical chest compressions devices (LUCAS™), rapid-response veno-arterial (VA-)ECMO (Cardiohelp, Maquet), and ECMO assisted revascularization in a dedicated clinical pathway will offer a potential lifesaving treatment option that is in accordance with the recommendations in the current Guidelines.

The aim of the study is to investigate the feasibility of a new local clinical pathway to provide ECPR for refractory OHCA patients.

Eligibility Criteria:
Inclusion Criteria:

* Witnessed arrest
* Bystander CPR initiated before EMS arrival or EMS-witnessed arrest
* VF/VT as first recorded rhythm by EMS or shock delivered by AED
* No ROSC within 10 minutes after EMS arrival
* Ambulance transport with mechanical chest compression device

Exclusion Criteria:

* Confirmation of ROSC
* End-tidal CO2 \< 10 mmHg
* Known terminal disease (eg. cancer)
* Known severe comorbidity

  * Severe chronic pulmonary disease (GOLD classification 3 or 4)
  * Heart failure NYHA classification 3 or 4
  * Known history of bifemoral surgery
* Do Not Resuscitate (DNR) order
* Expected time from transport decision to start ECMO \>60 minute