Risk factors for progression toward brain death after out-of-hospital cardiac arrest

Background: Successfully resuscitated out-of-hospital cardiac arrest (OHCA) may lead to brain death (BD) and good-quality transplantable organs. We aimed to determine risk factors for evolution toward BD after OHCA. We analyzed adult patients admitted to an intensive care unit (ICU) who survived at least 24 h after an OHCA between 2005 and 2015. BD was defined according to international guidelines. Multivariate logistic regression was used to identify potential risk factors for BD available 24 h after OHCA. Results: A total of 214 patients were included (median age 68 years; sex ratio 1.25; non-shockable OHCA: 88%). Among these, 42 (19.6%) developed BD, while 22 (10.3%) were alive at 1 year with a good neurological outcome. Independent risk factors for BD were age (OR per year 0.95; 95% CI [0.92-0.98]), female gender (OR 2.34; 95% CI [1.02-5.35]), neurological cause of OHCA (OR 14.72; 95% CI [3.03-71.37]), duration of the low-flow period > 16 min (OR 2.94, 95% CI [1.21-7.16]) and need of vasoactive drugs at 24 h (OR 6.20, 95% CI [2.41-15.93]). Conclusions: The study identified, in a population of OHCA with predominantly non-shockable initial rhythms, five simple risk factors independently associated with progression toward BD.