Improving outcome after out-of-hospital cardiac arrest by strengthening weak links of the local Chain of Survival; quality of advanced life support and post-resuscitation care☆

Abstract 

Background

Survival after out-of-hospital cardiac arrest (OHCA) depends on a well functioning Chain of Survival. We wanted to assess if targeted attempts to strengthen the weak links of our local chain; quality of advanced life support (ALS) and post-resuscitation care, would improve outcome.

Materials and methods

Utstein data from all OHCAs in Oslo during three distinct 2-year time periods 1996–1998, 2001–2003 and 2004–2005 were collected. Before the second period the local ALS guidelines changed with increased focus on good quality chest compressions with minimal pauses, while standardized post-resuscitation care including goal directed therapy with therapeutic hypothermia and percutaneous coronary intervention was added in the third period. Additional a priori sub-group analyses of arrests with cardiac aetiology as well as bystander witnessed ventricular fibrillation/tachycardia (VF/VT) arrests with cardiac aetiology were performed.

Results

ALS was attempted in 454, 449, and 417 patients with OHCA in the first, second and last time period, respectively. From the first to the third period VF/VT arrests declined (40% vs. 33%, p=0.039) and fewer arrests were witnessed (80% vs. 72%, p=0.022) and response intervals increased (7±4 to 9±4min, p<0.001). Overall survival increased from 7% (first period) to 13% (last period), p=0.002, and survival in the sub-group of bystander witnessed VF/VT arrests with cardiac aetiology increased from 15% (first period) to 35% (last period), p=0.001.

Conclusions

Survival after OHCA was increased after improving weak links of our local Chain of Survival, quality of ALS and post-resuscitation care.

Keywords: Advanced life support (ALS), Ambulance, Cardiac arrest, Cardiopulmonary resuscitation (CPR), Emergency medical services, Guidelines, Out-of-hospital CPR, Outcome, Post-resuscitation period, Resuscitation, Sudden cardiac death, Utstein template