The impact of a pre-hospital critical care team on survival from out-of-hospital cardiac arrest.
To assess the impact of a pre-hospital critical care team (CCT) on survival from out-of-hospital cardiac arrest (OHCA). We undertook a retrospective observational study, comparing OHCA patients attended by advanced life support (ALS) paramedics with OHCA patients attended by ALS paramedics and a CCT between April 2011 and April 2013 in a single ambulance service in Southwest England. We used multiple logistic regression to control for an anticipated imbalance of prognostic factors between the groups. The primary outcome was survival to hospital discharge. All data were collected independently of the research. 1851 cases of OHCA were included in the analysis, of which 1686 received ALS paramedic treatment and 165 were attended by both ALS paramedics and a CCT. Unadjusted rates of survival to hospital discharge were significantly higher in the CCT group, compared to the ALS paramedic group (15.8% and 6.5%, respectively, p<0.001). After adjustment using multiple logistic regression, the effect of CCT treatment was no longer statistically significant (OR 1.54, 95% CI 0.89-2.67, p=0.13). Subgroup analysis of OHCA with first monitored rhythm of ventricular fibrillation or pulseless ventricular tachycardia showed similar results. Pre-hospital critical care for OHCA was not associated with significantly improved rates of survival to hospital discharge. These results are in keeping with previously published studies. Further research with a larger sample size is required to determine whether CCTs can improve outcome in OHCA.