Abstract TMP74: Evaluation of NIHSS-Onset to Groin Time and Prehospital Acute Stroke Severity Scale-onset to Groin Time Scores in Prediction of Outcomes After Endovascular Treatment in Acute Ischemic Stroke Patients: A Retrospective Single-center Study

Abstract

Background: Prehospital triage tools are essential to identify large vessel occlusion (LVO) in order to triage patients to a comprehensive stroke center for timely endovascular treatment (ET). Prehospital Acute Stroke Severity Scale (PASS) (score range 0-3) was recently identified as a valuable tool to predict LVO. Several studies have shown that in patients treated with IV tPA, a score calculated by multiplying admission NIHSS by the time from symptom onset to tPA treatment (in hours) can predict outcome. In our study, we applied similar concept for patients with LVO who underwent successful ET. Methods: We retrospectively reviewed all LVO patients between January 2015 and June 2016 who received ET. We analyzed the association of time of symptom onset to groin time (OGT), NIHSS, PASS, NIHSS-OGT, and PASS-OGT with modified Rankin scale (mRS) at the time of discharge. Results: Fifty-four patients underwent ET during the study period. Patients with posterior circulation LVO and those treated after 6 hours from last known normal were excluded. A total of 34 patients were left for final analysis. Patients with a good outcome (mRS ≤2) had an average NIHSS-OGT score of 43.2 (95% CI: 29.7-56.8) and PASS-OGT score of 5.52 (95% CI: 4.48-6.56). Patient’s with poor to miserable outcomes (mRS 3-6) average NIHSS-OGT 84.7 (95% CI: 72.8-96.6) and PASS-OGT average 9.8 (95% CI: 8.3-11.2). For NIHSS-OGT cut off of 55 the sensitivity and specificity was 0.75 and 0.85 respectively; diagnostic odds ratio 16.5 (96% CI: 2.41-112.83). For PASS-OGT cut off of 6.5 the sensitivity and specificity were 0.88 and 0.76 respectively; diagnostic odds ratio 23.33 (95% CI: 2.37-229.33). The wide confidence intervals can be attributed to small sample size. Conclusion: Our study indicates NIHSS–OGT and PASS-OGT scores have a linear relationship with discharge mRS and can reliably predict early clinical outcomes after ET. Further confirmation with randomized control trials is needed.