Is hospital care of major importance for outcome after out-of-hospital cardiac arrest?

Abstract

Aim: To describe patient characteristics, hospital investigations and interventions and early mortality among patients being hospitalized after out-of-hospital cardiac arrest in two hospitals. Setting: Municipality of Göteborg, Sweden. Patients: All patients suffering an out-of-hospital cardiac arrest who were successfully resuscitated and admitted to hospital between 1 October 1980 and 31 December 1996. All patients were resuscitated by the same Emergency Medical Service and admitted alive to one of the two city hospitals in Göteborg. Results: Of 579 patients admitted to Sahlgrenska Hospital, 253 (44%) were discharged alive and of 459 patients admitted to Östra Hospital, 152 (33%) were discharged alive (P<0.001). More patients in Sahlgrenska Hospital were still receiving cardiopulmonary resuscitation (CPR) treatment (P=0.03), but patients in Östra had a lower systolic blood pressure and higher heart rate on admission. A larger percentage of patients admitted to Sahlgrenska Hospital underwent coronary angiography (P<0.001), electrophysiological testing (P<0.001), Holter recording (P<0.001), echocardiography (P=0.004), Percutaneous Transluminal Coronary Angioplasty (PTCA, P=0.009), implantation of Automatic Implantable Cardioverter Defibrillator (AICD, P=0.03) and exercise stress tests (P=0.003). Inhabitants in the catchment area of Östra hospital had a less favourable socio-economic profile. Conclusion: Survival after out-of-hospital cardiac arrest may be affected by the course of hospital management. Other variables that might influence survival are socio-economic factors and cardiorespiratory status on admission to hospital. Further investigation is called for as more patients are being hospitalised alive after out-of-hospital cardiac arrest.

Introduction

In the past 2 or 3 decades, considerable efforts have been made to describe factors associated with out-of-hospital cardiac arrest [1], [2], [3], [4]. Since the introduction of the Utstein reporting style [3], detailed intersystem comparison is at last possible. The ‘chain of survival’ concept [4], is now a widely established description of prehospital measures, each with an effect on survival. An increasing percentage of these patients are now being hospitalised and discharged alive. This is confirmed by two recently published European reports [5], [6], in which the survival-to-discharge rates for witnessed out-of-hospital ventricular fibrillation have risen to the region of 35%. Most of the studies of out-of-hospital cardiac arrest published so far have focused on factors related to the Emergency Medical Services (EMS), including time intervals during EMS activation and resuscitation, the presence of a bystander performing cardiopulmonary resuscitation (CPR), the training level of EMS crews and the number of tiers. Since prehospital factors have proven themselves in several studies to have a major effect on the patients outcome [5], [7], [8], [9], this focus is easily understood. However, with a growing percentage of patients admitted to emergency departments (ED), intensive care and modern cardiological investigations and interventions, we believe that the importance of the hospital phase of management of out-of-hospital cardiac arrest may increase.

The aim of this study was to describe patient characteristics, in-hospital investigations and interventions and early mortality among patients resuscitated after out-of-hospital cardiac arrest. To achieve this, we examined the medical history, and prehospital and hospital course of two cohorts of patients suffering an out-of-hospital cardiac arrest and recruited from the same municipality and resuscitated by the same EMS but admitted to one of the two city hospitals.