Abstract 11969: Survival From Out-of-Hospital Cardiac Arrest: Intravenous Versus Intraosseous Resuscitation

Abstract

Background: Although administration of drugs by intraosseous vascular access during out-of-hospital cardiac arrest (OHCA) is growing in popularity and prevalence, the actual effectiveness of this treatment approach is uncertain. Hypothesis: We hypothesized that there would be no difference in resuscitation outcome as measured by survival to hospital discharge after OHCA based on the mode of drug delivery. Methods: We performed a retrospective cohort study of emergency medical services (EMS)-treated, non-traumatic OHCA among persons >18 years of age in King County, WA (excluding Seattle) between September 1, 2012 through December 31, 2014. Patients were classified as IV or IO treatment recipients based on the route of first drug administered during OHCA. Study outcomes were analyzed by multivariate logistic regression. The primary outcome investigated was survival to hospital discharge. Secondary outcomes measured were sustained return of spontaneous circulation (ROSC) and survival to hospital admission. Results: Among 1241 adults with OHCA in whom the time to vascular access was known, 1021 were treated via IV and 220 via IO routes. Patients comprising the IO group were younger, included more women, were more likely to have had an unwitnessed OHCA, an arrest of non-cardiac etiology and less likely to have a shockable initial rhythm than IV patients. IO drug recipients were less likely to achieve sustained ROSC, survive to hospital admission or survive to hospital discharge than the IV group. In adjusted analyses, compared to the IV group, recipients of IO medications were less likely to achieve sustained ROSC (odds ratio (95% confidence interval (CI) 0.69 (0.5, 0.95), p = 0.02) with a trend toward a lower likelihood of being admitted alive to hospital (odds ratio (95% CI) 0.72 (0.52, 1.01), p = 0.06), but there were no differences between the two groups in survival to discharge (odds ratio (95% CI) 0.87 (0.54, 1.40), p = 0.56). Conclusion: IO as compared with IV access is independently associated with a lower likelihood of achieving sustained ROSC after OHCA and a trend toward decreased hospital admission, but not survival to hospital discharge.