Characteristics and outcome among patients suffering from out-of-hospital cardiac arrest with the emphasis on availability for intervention trials.

AIM

To describe all patients treated for out-of-hospital cardiac arrest (OHCA) according to the Utstein criteria and their characteristics and outcome with emphasis on whether they were available for early intervention trials.

DESIGN

Retrospective analysis of a study where data were collected prospectively.

SETTING

The Municipality of Göteborg/Mölndal in Sweden.

PATIENTS

All patients suffering from out-of-hospital cardiac arrest in the Municipality of Göteborg/Mölndal in whom cardiopulmonary resuscitation (CPR) was attempted between May 2003 and May 2005.

INTERVENTIONS

Part of the study cohort, i.e. patients with a witnessed, non-traumatic, out-of-hospital cardiac arrest were distributed (cluster) to mechanical (LUCAS) or manual chest compression.

RESULTS

The overall survival to discharge from hospital among the 508 patients was 8.5%. The corresponding value for non-cardiac cases was 5.1% and for cardiac cases if crew witnessed 16.1%, bystander witnessed 12.7% and non-witnessed 1.4%. Fifty-nine percent of the patients fulfilled the inclusion criteria for the trial and had no exclusion criteria and 9.7% of these survived to discharge. Ten percent of patients fulfilled the inclusion criteria but were excluded and 20.4% survived to discharge. Thirty-one percent of patients did not fulfil the inclusion criteria and 2.5% survived. Among patients included in the LUCAS group, many of the survivors, 10/13 (77%), experienced a rapid return of spontaneous circulation (ROSC) before the application of the device.

CONCLUSION

Among patients with OHCA in whom CPR was started 8.5% survived to hospital discharge and 59% were theoretically available for an early intervention trial. These patients have a different outcome compared with patients not available. However, among those available, the majority of survivors had a rapid ROSC before the application of the intervention (LUCAS). This raises concerns about the potential for early intervention trials to improve outcome after OHCA.