Background In 2020, there were 4,352 people waiting for organ transplantation in Canada. A rise in demand has led to national exploration of non-traditional pathways for organ donation to increase the potential pool of donors and subsequent transplant recipients. Donation after Cardiac Death (DCD) has become a promising option across Canada and in other jurisdictions worldwide. One unexplored aspect to uncontrolled DCD (uDCD) in Canada is the inclusion of patients who suffer an out-of-hospital cardiac arrest (OHCA) into the pool of potential donors, of which there are an estimated 40,000 each year in Canada. The primary objective of this study is to quantify the potential pool of donors that would be eligible for uDCD subsequent to OHCA. This will allow us to understand how many potential donors are being missed when treated, but not transported after an OHCA.

Methods A retrospective observational cohort study will be undertaken, using pre-existing data from the Canadian Resuscitation Outcomes Consortium (CanROC) registry, a pan- Canadian registry that collects prospective OHCA data. Consecutive OHCA cases from January 1, 2016 - December 31, 2018 meeting inclusion criteria will be included.

Results Descriptive analysis will be used to examine patient and event characteristics, and determine the proportion of patients who meet the indication for uDCD. Results will be reported as mean (standard deviation [SD]) or median (interquartile range [IQR]) for continuous variables and frequency (%) for categorical variables.

Conclusions Preliminary literature review suggests uDCD subsequent to OHCA is a viable opportunity to increase the donor pool in Canada. Presently, there is a lack of understanding of this pool of potential donors, and no programs exist in Canada to recruit from this population. In order to determine if pursuing uDCD subsequent to OHCA to improve organ donation rates is worthwhile, we must first quantify its potential.