For patients with out-of-hospital cardiac arrest (OHCA), outcomes differ by time to first cardiopulmonary resuscitation (CPR) and first documented rhythm, according to a study published online April 30 in Circulation: Cardiovascular Quality and Outcomes.

As the time from collapse to CPR was delayed, there was an increase in the proportion of asystole, and decreases in those of pVT/VF and PEA (P < 0.001). As first CPR was delayed, the estimated incidences of end point after OHCA became lower, regardless of the type of first documented rhythm; however, these differed by the rhythm.