Abstract 213: Sensitivity and Specificity of Paramedic Judgment for Determining Cardiac Etiology of Arrest
BACKGROUND: On-scene paramedics (PMs) document the presumed etiology of out-of-hospital cardiac arrests (OHCA) for whom resuscitation is attempted in our EMS system. We sought to characterize the sensitivity and specificity of PM judgment regarding a cardiac cause of arrest.
METHODS: We calculated the sensitivity (SN) of PM presumed cardiac etiology among adult OHCA victims when compared to a gold standard of both autopsy-proven myocardial ischemia (MI) combined with survivors who underwent PCI or CABG after hospital admission. Specificity (SP) was estimated from autopsy cases in which MI was not considered causal. Multivariate logistic regression was used to assess the independent predictive ability of PM judgment, controlling for known predictors.
RESULTS: We analyzed 253 cases of OHCA (221 autopsy cases and 32 survivors who underwent PCI or CABG). SN for a cardiac etiology was 106/113 (0.94, 95% CI 0.88-0.97). SP was 49/140 (0.35, 95% CI 0.27-0.44). The positive and negative likelihood ratios for PM judgment in determining a cardiac cause of arrest were 1.44 (95% CI 1.27-1.64) and 0.18 (95% CI 0.08-0.38), respectively. Multivariate logistic demonstrated PM judgment is an independent predictor of a cardiac cause of arrest (TABLE).
CONCLUSIONS: PM presumption of a non-cardiac cause substantially decreases the likelihood of myocardial ischemia as a cause of arrest in the setting of OHCA. PM judgment alone is likely insufficiently predictive to rule in or out a cardiac cause of arrest. However, PM judgment independently increases the odds of a cardiac cause when controlling for other predictors.
Author Disclosures: M.P. Mallin: None. S. Hartsell: None. S. Youngquist: Speakers Bureau; Modest; Physio-Control. Consultant/Advisory Board; Modest; Keytechnic.
- © 2014 by American Heart Association, Inc.