103 Comparison of the Vision, Aphasia, Neglect Test With the Los Angeles Motor Scale in Out-of-Hospital Assessment for Large Vessel Strokes

Abstract

Our Emergency Medical Services (EMS) system conducted this study in order to evaluate the utility of the Los Angeles Motor Scale (LAMS) score in conjunction with a modified vision, aphasia, neglect (VAN) test in predicting medical intervention and neurological outcomes after acute stroke, with the goal of identifying large vessel occlusions (LVOs), the most deadly type of stroke. This Institutional Review Board (IRB)-approved prospective study included all patients (n=364) transported for stroke by our EMS system from December 2018-March 2019. Patients were administered the LAMS and VAN test by paramedics prior to hospital arrival. A LAMS score of 4 or 5 was considered high for the purposes of our study. Patients were considered VAN positive if they were deficient in any of the three areas it tests. The median age was 71, with an interquartile range (IQR) of 62-80 and a range of 13-108. Our cohort was 49% female. The median scene time was 16 minutes, with an IQR of 13-19 minutes and a range of 4-47 minutes. We compared the scene time of our cohort with the data from January 2016-November 2018 (n=2100 patients) who only received the LAMS. Using a Wilcoxon rank-sum test, we found that the distributions differed with a p-value of .044. However, the difference was very small: our previous study found a median time of 15 minutes with an IQR of 12-19. The LAMS/VAN breakdown (n=288 patients who received both) was as follows:Low LAMS/Negative VAN: 29%High LAMS/Negative VAN: 8%Low LAMS/Positive VAN: 43%High LAMS/Positive VAN: 20%71% of patients had high LAMS or positive VAN. Overall, 26% received computed tomography (CT) perfusion imaging, 16% received tissue plasminogen activator (tPA), and 7% received mechanical intervention. 8% of strokes were hemorrhagic, 43% were ischemic, and 12% were transient ischemic attacks (TIA). The median National Institute of Health Stroke Score (NIHSS) at hospital arrival was 6, with an IQR of 2-12 and a range of 0-36. 50% of patients were discharged home, 18% were sent to a skilled nursing facility, 11% were discharged to rehab, and 5% expired. Table 1 summarizes the p-values associated with certain outcome-scale combinations, calculated using Fisher’s exact test or Wilcoxon’s rank-sum test (NS = not significant).Table 1p-values associated with Outcome-Scale combinationsReceived CT PerfusionReceived tPAReceived Mechanical InterventionIschemic StrokeHigher NIHSS @ Hospital ArrivalHigher EMS Rankin ScoreLonger Hospital StayNot discharged homeHigh LAMS.0160NS<.0001.0004<.0001NS.0448.0048Positive VANNSNSNS.0074.0102NSNSNSHigh LAMS or Positive VANNS.0363.0273.0019<.0001NSNSNSHigh LAMS and Positive VAN.0351NS<.0001.0009<.0001NSNSNS Open table in a new tab The cohort of patients with a high LAMS and negative VAN (n=23) had 26% receive CT perfusion, 18% receive tPA, 14% receive mechanical intervention, were 45% ischemic strokes, and had a median NIHSS of 8.5 with an IQR of 6-17.75. The LAMS combined with the modified VAN is no more effective than the LAMS alone. In this study, the use of the LAMS score alone yielded the most effective results in predicting intervention and outcomes for acute stroke. Requiring both a high LAMS and a positive VAN excludes the group of patients with high LAMS and negative VAN, who still had significantly worse outcomes compared to the cohort overall.