Effect of bystander initiated cardiopulmonary resuscitation on ventricular fibrillation and survival after witnessed cardiac arrest outside hospital.

Abstract

Objective-To describe the proportion of patients who were discharged from hospital after witnessed cardiac arrest outside hospital in relation to whether a bystander initiated cardiopulmonary resuscitation. Patients-Al1 patients with witnessed cardiac arrest outside hospital before arrival of the ambulance and in whom cardiopulmonary resuscitation was attempted by the emergency medical service in Gothenburg during 1980-92. Results-Cardiopulmonary resuscitation was initiated by a bystander in 18% (303) of 1660 cases. In this group 69% had ventricular fibrillation at first recording compared with 51% in the remaining patients (P < 0.001). Among patients in whom cardiopulmonary resuscitation had been initiated by a bystander 25% were discharged alive versus 8% of the remaining patients (P < 0.001). Independent predictors of survival were in order of significance: initial arrhythmia (P < 0.001), interval between collapse and arrival of first ambulance (P < 0.001), cardiopulmonary 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 brain damage and died in hospital. Corresponding figures for death in association with myocardial damage were 18% and 290/o respectively (P < 0-01).

Experiences from treatment of out-of-hospital cardiac arrest during 17 years in Göteborg

“…This could be looked upon as a disappointing finding. The increase in bystander cardiopulmonary resuscitation [6][7][8] as well as a shortened interval from collapse to defibrillation should both increase the proportion of patients found in ventricular fibrillation. However, the increasing age of the victims might indicate a higher proportion of patients with severe underlying disease which could lower the possibility of finding them in ventricular fibrillation.…”

Combined Interventions May Improve Success When Treating Sudden Cardiac Arrest

“…In 1994, Herlitz et al demonstrated a three-fold increase in survival of VF patients who received bystander CPR as compared with the study group who did not receive bystander CPR. 7 The King County, Washington, group led by Rea compared survival rates for adult cardiac arrest victims who received no bystander CPR, those who received bystander CPR before EMS arrival requiring dispatcher instruction, and those who received bystander CPR without dispatcher assistance. In addition to finding a 25% increase in the rate of bystander CPR when dispatcher-assisted CPR was utilized, the researchers noted that dispatcher-assisted bystander CPR increased survival.…”

Minimal interruption of cardiopulmonary resuscitation for a single shock as mandated by automated external defibrillations does not compromise outcomes in a porcine model of cardiac arrest and resuscitation

“…After prolonged untreated cardiac arrest, severe and progressive energy imbalances develop (26 -28). Chest compressions produce approximately 46% of the prearrest stroke volume values (29), restore minimal myocardial and cerebral blood flows, and thereby prime the heart for successful defibrillation and minimize ischemic brain damage (30).…”