Background: While there is a growing body of research in the field of post-cardiac arrest outcomes and survivorship, the lived experience of close family members who witness the arrest itself and who may have performed CPR, has not been specifically explored. Methods: We employed qualitative interpretive descriptive methodology using key informant interviews for data collection. Participants were recruited internationally, and interviews were conducted virtually following a semi-structured format. Thematic data analysis was conducted using a constant comparative approach. Results: Interviews were conducted with 33 family members who were present at the time of their loved ones cardiac arrest. Across the participant stories, we identified the core concept of 'base trauma' that centres around what family member witnesses initially experience at the time of the arrest itself. We postulate that this core theme influences six significant patterns of experience including: 1) feelings of responsibility, 2) fear of recurrence without them, 3) the impact of reliving the event, 4) the inability to escape triggers, 5) the delayed realization of their own trauma, and lastly 6) dealing with psychologic disconnect. Conclusions: There is increasing research evidence that family members of cardiac arrest survivors have their own challenges as part of the recovery journey. We introduce novel concept of the compounded impact of the initial base trauma those that witness and respond to a loved ones cardiac arrest have. The nuanced experiences of this group point to the need to normalize their experience as a 'trauma' and suggest that support pathways need to recognize this.