Pre-hospital ECMO or Conventional Resuscitation for Refractory Cardiac Arrest

PACER:Pre-hospital ECMO or Conventional Resuscitation for Refractory Cardiac Arrest. An Investigator Initiated, Parallel Group, Assessor-blinded, Registry Embedded, Randomised Controlled Pilot Trial

This pilot study aims to determine feasibility of randomising patients to receive pre-hospital Extracorporeal Cardiopulmonary Resuscitation (ECPR) compared to conventional cardiac arrest care for refractory out of hospital cardiac arrest (OHCA).

The success of this study will be measured by the number of patients recruited into the study successfully treated with the treatment they were randomised to receive in the pre-Hospital setting.

Conventional cardiac arrest care, including high performance cardiopulmonary resuscitation, defibrillation and administration of drugs such as adrenaline is the current treatment for out of hospital cardiac arrest. In cases where this treatment does not see spontaneous circulation restored promptly, the patients cardiac arrest is termed refractory. Refractory Cardiac arrest is coupled with an increased risk of hypoxic injury to vital organs and the prospect of survival with good neurological recovery decreases dramatically.

ECPR is an effective way to restore circulation for patients with refractory OHCA. Hospital based ECPR is the most common process by which refractory OHCA patients are treated with ECPR. Patients are transported to an ECPR capable hospital while receiving mechanical CPR. Transporting patients while receiving mechanical CPR is challenging and may lead to less effective CPR (low flow). It may also delay access to urgent hospital based treatments due to the extra time required to load a patient receiving mechanical CPR.

Pre-Hospital ECPR is where the ECMO team rapidly attends the scene and implements ECMO while CPR is on-going at the scene. Benefits of this approach may include reduced low-flow time due to both earlier ECMO initiation as well as allowing the emergency responders focus on delivering high performance CPR rather than loading the patient for transport.

The results of this study will inform a larger study where researchers will compare these two treatments to determine if ECPR leads to higher survival rates and better recovery for patients with refractory OHCA. Observational data for pre-hospital ECPR in the Australian setting looks promising. However ECPR systems are expensive and resource intensive, making answering this question an imperative.

Inclusion Criteria:

• Adult patients 18-70 years old
• Witnessed cardiac arrest
• Bystander CPR
• Refractory cardiac arrest (>20 mins, but <45 mins)
• Initial cardiac rhythm VF, VT or PEA
• Within hours of PACER service operation (e.g. mon-fri 0800-1700)
• Within 25 mins of rapid response ambulance (code 1 lights and sirens)

Exclusion Criteria:

• Initial cardiac rhythm asystole
• ROSC with sustained recovery
• Technically not possible to perform percutaneous cannulation
• Evidence of/suspectedSignificant end stage disease:
• Severe disability impairing activities of daily living
• End-stage organ - cardiac, liver, lung, renal
• Other life-limiting diseases e.g malignancy, terminal illness
• Advance health care directive (not for resuscitation)