Presentation, management, and outcome of out of hospital cardiopulmonary arrest: comparison by underlying aetiology.

OBJECTIVE To describe and compare presentation, management, and survival by aetiology of cardiopulmonary arrest. DESIGN, SETTING, AND PATIENTS A retrospective cohort study was undertaken of all 21 175 first out of hospital cardiopulmonary arrests in Scotland between May 1991 and March 1998. MAIN OUTCOME MEASURE Discharge alive from hospital. RESULTS Presumed cardiac disease accounted for 17 451 cases (82%), other internal aetiologies for 1814 (9%), and external aetiologies for 1910 (9%). Arrests caused by presumed cardiac disease had a better risk profile in terms of presence of a witness, bystander cardiopulmonary resuscitation, call-response interval, and use of defibrillation; 1265 (7%) of those who arrested from presumed cardiac disease were discharged alive, compared with only 77 (2%) of those with non-cardiac disorders (p < 0.001). Among those defibrillated, call-response interval was associated with survival following arrests from both presumed cardiac and non-cardiac causes (p < 0.001). CONCLUSIONS Out of hospital cardiopulmonary arrests from non-cardiac causes were associated with worse crude survival than arrests from cardiac causes. Improvements in call-response interval and basic life support skills in the community would improve survival irrespective of the aetiology and should therefore be encouraged.