Advanced rescuer- versus citizen-witnessed cardiac arrest: Is there a difference in outcome?
BACKGROUND
Substantial financial and human resources are invested in training and maintaining advanced life support (ALS) skills of paramedics who are deployed to the field in response to out-of-hospital cardiac arrest. It would be expected that patients who experience cardiac arrest in the presence of a trained health care practitioner, such as a paramedic, have better outcomes.


OBJECTIVE
To compare the rates of return of spontaneous circulation (ROSC), survival to hospital admission (SHA), and survival to hospital discharge (SHD) between paramedic-witnessed out-of-hospital cardiac arrest vs. citizen-witnessed out-of-hospital cardiac arrest.


METHODS
In this retrospective cohort study, the records of all out-of-hospital nontraumatic cardiac arrest patients presenting to a municipal teaching hospital from November 1, 1994, through June 30, 2008, were reviewed. The age, gender, race, rhythm on paramedic arrival, presence of bystander cardiopulmonary resuscitation (CPR), whether it was a witnessed arrest and, if witnessed, whether it was a paramedic-witnessed arrest, site of the arrest, and the rate of SHD were noted. A univariate odds ratio was computed to describe the association between paramedic-witnessed out-of-hospital cardiac arrest vs.citizen-witnessed out-of-hospital cardiac arrest and SHD. A multivariable logistic regression analysis was also performed, controlling for age, gender, arrest rhythm, bystander CPR, and site of arrest.


RESULTS
Of the total cohort of 1,294 out-of-hospital cardiac arrests, 750 (52.6%) were either paramedic-witnessed (154/750 = 20.5%) or citizen-witnessed (596/750 = 79.5%). Among the witnessed cardiac arrests, overall the SHD was 53 of 750 (7.1%). On univariate analysis, the ROSC, SHA, or SHD rates were not statistically significantly different between paramedic- and citizen-witnessed arrests. Even after multivariable adjustment, the ROSC, SHA, and SHD rates were not significantly different between paramedic- and citizen-witnessed arrests.


CONCLUSIONS
Among our study population of out-of-hospital cardiac arrest victims, paramedic-witnessed arrests did not appear to have improved survival rates when compared with citizen-witnessed arrests.
Kaji
Amy H
AH
Department of Emergency Medicine, Harbor-UCLA Medical Center, Torrance, California, USA.
Hanif
Arslan M
AM
Niemann
James T
JT
D000368:Aged; D000369:Aged, 80 and over; D016887:Cardiopulmonary Resuscitation / Q000706:statistics & numerical data*; D016001:Confidence Intervals; D004632:Emergency Medical Services; D004634:Emergency Medical Technicians / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality / Q000628:therapy*; D012189:Retrospective Studies; D013223:Statistics as Topic; D016896:Treatment Outcome