EFFECT OF BYSTANDER INITIATED CARDIOPULMONARY-RESUSCITATION ON VENTRICULAR-FIBRILLATION AND SURVIVAL AFTER WITNESSED CARDIAC-ARREST OUTSIDEHOSPITAL

Objective-To describe the proportion of patients who were discharged f rom hospital after witnessed cardiac arrest outside hospital in relati on to whether a bystander initiated cardiopulmonary resuscitation. Pat ients-All patients with witnessed cardiac arrest outside hospital befo re arrival of the ambulance and in whom cardiopulmonary resuscitation was attempted by the emergency medical service in Gothenburg during 19 80-92. Results-Cardiopulmonary resuscitation was initiated by a bystan der in 18% (303) of 1660 cases. In this group 69% had ventricular fibr illation at first recording compared with 51% in the remaining patient s (P < 0.001). Among patients in whom cardiopulmonary resuscitation ha d been initiated by a bystander 25% were discharged alive versus 8% of the remaining patients (P < 0.001). Independent predictors of surviva l were in order of significance: initial arrhythmia (P < 0.001), inter val between collapse and arrival of first ambulance (P < 0.001), cardi opulmonary resuscitation initiated by a bystander (P < 0.001), and age (P < 0.01). Among patients who were admitted to hospital alive 30% of patients in whom cardiopulmonary resuscitation had been initiated by a bystander compared with 58% of remaining patients (P < 0.001) had br ain damage and died in hospital. Corresponding figures for death in as sociation with myocardial damage were 18% and 29% respectively (P < 0. 01). Conclusions-Cardiopulmonary resuscitation initiated by a bystande r maintains ventricular fibrillation and triples the chance of survivi ng a cardiac arrest outside hospital. Furthermore, it seems to protect against death in association with brain damage as well as with myocar dial damage.