Stepcare Extended Follow-up Substudy

All OHCA participants randomized in the STEPCARE trial at the extended follow-up participating sites, who survive and provide consent, with no further inclusion or exclusion criteria.

The inclusion and exclusion criteria for the STEPCARE trial are:

• Inclusion criteria: out-of-hospital cardiac arrest of non-traumatic origin, minimumof 20 minutes without chest compressions (defined as stable return of spontaneouscirculation. ROSC), unconsciousness (defined as not being able to obey verbalcommands equal to a FOUR-score motor response of <4, or being intubated and sedatedbecause of agitation after sustained ROSC, eligible for intensive care withoutrestrictions or limitation, inclusion within 4 hours (240 minutes) of ROSC (or 220minutes of stable ROSC).

• Exclusion criteria: on ECMO prior to randomization, pregnancy, suspected orconfirmed intracranial hemorrhage, previously randomized in the STEPCARE trial.

For caregivers, the eligibility will be that they live with, or have weekly or more frequent contact (in person or over the telephone) with the post OHCA survivor. Only one nominated caregiver per post OHCA survivor will be able to be included in the study. This would typically be the caregiver that would identify as the primary caregiver of the post OHCA survivor if needed, but may also be another close family member.