Critical Event Intervals in Determining Candidacy for Intravenous Thrombolysis in Acute Stroke.

Background: The aim of the study was to determine the optimal set point for the critical event benchmarks described in stroke guidelines and validate the ability of these goals to predict successful administration of intravenous thrombolysis within 60 min of hospital arrival.

Methods: This was a retrospective cohort analysis of patients with acute ischemic stroke who received intravenous thrombolysis following presentation to the emergency department. The national benchmarks for time intervals associated with the completion of critical events required to determine candidacy for thrombolysis were evaluated for the ability to predict successful administration of thrombolysis within 60 min of hospital arrival. Optimal time interval cut points were then estimated using regression and receiver-operator characteristic curve analysis and compared to guidelines.

Results: Of the 523 patients included in the analysis, 229 (43.8%) received intravenous thrombolysis within 60 min of hospital arrival. Of the patients who met the critical event interval goals described in guidelines, only 51.6% received thrombolysis within 60 min. The optimized cut points suggested by the regression analysis aligned with the guideline benchmarks with the only substantial difference being a shortened goal of arrival to neuroimaging start time of 19 min. This difference did not impact the overall predictive value.

Conclusion: The critical event benchmarks proposed in this study by logistic regression closely correlate with the critical event benchmarks described in the AHA/ASA acute stroke guidelines.