One out of three bystanders of out-of-hospital cardiac arrests shows signs of pathological psychological processing weeks after the incident - results from structured telephone interviews.

Background: Witnessing an out-of-hospital cardiac arrest (OHCA) is a traumatic experience. This study analyses bystanders` psychological processing of OHCA. We examined the potential impact of bystanders performing resuscitation and the influence of the relationship between bystander and patient (stranger vs.