Granfeldt A, et al. - In view of the observation that chronic obstructive pulmonary disease (COPD) is associated with a non-shockable rhythm in out-of-hospital cardiac arrest (OHCA), the severity of the underlying disease related to the presenting rhythm was determined. An association between incremental severity of COPD with increasing prevalence of a non-shockable rhythm as a presenting rhythm in OHCA patients was shown.