DSMB recommendation to stop

Prague out-of Hospital Cardiac Arrest (OHCA) study is a prospective randomized multicenter clinical study comparing use of prehospital intraarrest hypothermia, mechanical chest compression device, extracorporeal life support (ECLS) and early invasive investigation and treatment (coronary angiography/percutaneous coronary intervention [PCI]; pulmonary angiography/percutaneous embolectomy; aortography) in all patients with OHCA of presumed cardiac origin compared to standard of care. It is hypothesized, that above stated "hyperinvasive" approach might improve outcome of out-of hospital cardiac arrest victims.

Background: Out of hospital cardiac arrest (OHCA) has a poor outcome. Recent non-randomized study of ECLS (extracorporeal life support) in OHCA suggested further prospective multicenter studies to define population with OHCA that would benefit from ECLS.

Aim: to perform a prospective randomized multicenter clinical study comparing use of prehospital intraarrest hypothermia, mechanical chest compression device, ECLS and early invasive investigation and treatment (coronary angiography/percutaneous coronary intervention [PCI]; pulmonary angiography/percutaneous embolectomy; aortography) in all patients with OHCA of presumed cardiac origin compared to standard of care.

Planned intervention: patients with witnessed OHCA without ROSC (return of spontaneous circulation) after a minimum of 5 minutes of ACLS by emergency medical service (EMS) team will be after fulfilling of inclusion/exclusion criteria for the study randomized in a 1:1 design to standard vs. hyperinvasive arm. Patients in standard arm will be further managed as per recent guidelines. In hyperinvasive arm, mechanical compression device together with intranasal cooling will be immediately instituted and patients will be transferred to cardiac center directly to cathlab under ongoing CPR. After admission to cathlab, overall status, ROSC and ECLS inclusion/exclusion criteria will be evaluated and in case of no contraindications to ECLS and no ROSC or ROSC with shock, veno-arterial ECLS will be started as soon as possible, not later than 60 minutes after cardiac arrest onset. After ECLS institution, mild hypothermia will be continued by means of ECLS cooling and immediate invasive investigation will be performed in all patients.

Standard postresuscitation care will follow.

Inclusion Criteria:

• minimum of 18 and maximum of 65 years
• witnessed out-of-hospital cardiac arrest of presumed cardiac cause
• minimum of 5 minutes of ACLS performed by emergency medical service team without sustained ROSC
• unconsciousness (Glasgow Coma Score < 8)
• ECMO team and bed-capacity in cardiac center available.

Exclusion Criteria:

• OHCA of presumed non-cardiac cause
• unwitnessed collapse
• pregnancy
• sustained ROSC within 5 minutes of ACLS performed by EMS team
• conscious patient
• known bleeding diathesis or suspected or confirmed acute or recent intracranial bleeding
• suspected or confirmed acute stroke
• known severe chronic organ dysfunction or other limitations in therapy
• "do not resuscitate" order or other circumstances making 180 day survival unlikely
• known pre-arrest cerebral performance category CPC ≥ 3.