Influence of ambulance crew's length of experience on the outcome of out-of-hospital cardiac arrest.

Abstract

To investigate whether an ambulance crew's length of experience affected the outcome of out-of-hospital cardiac arrest. This was a population-based, retrospective observational study of attempted resuscitations in 1547 consecutive arrests of cardiac aetiology by Nottinghamshire Emergency Ambulance Service crew. One thousand and seventy-one patients were managed by either a paramedic or a technician crew without assistance from other trained individuals at the scene of arrest. Overall, the chances of a patient surviving to be discharged from hospital alive did not appear to be affected by the paramedic's length of experience (among survivors, 18 months experience vs non-survivors 16 months experience, P = 0.347) but there appears to be a trend in the effect of a technician's length of experience on survival (among survivors, 60 months experience vs non-survivors 28 months experience, P = 0.075). However, when a technician had 4 years of experience or more and a paramedic 1 year's experience, survival rates did improve. Logistic regression analysis, adjusted for factors known to influence outcome, revealed that chances of survival increased once technicians had over 4 years of experience after qualification (odds ratio 2.71, 95% CI 1.17 to 6.32, P = 0.02) and paramedics after just 1 year of experience (odds ratio 2.68, 95% CI 1.05 to 6.82, P = 0.04). Survival from out-of-hospital cardiac arrest varies with the type of ambulance crew and length of experience after qualification. Experience in the field seems important as paramedics achieve better survival rates after just 1 year's experience, while technicians need to have more than 4 years' experience to improve survival.