Abstract WP236: Utility of the Los Angeles Motor Score in Predicting Large Vessel Occlusions

• Published in: Stroke (1970) 2018-01, Vol.49 (Suppl_1)
• Main Authors: Brandler, Ethan S, Perez, Karol, Boddepalli, Raja, Thode, Henry C
• Format: Article
• Language: English
• ISSN: 0039-2499; 1524-4628
• DOI: 10.1161/str.49.suppl_1.WP236

Abstract only Background: Studies have documented the effectiveness of endovascular therapies in large vessel occlusions (LVO). Since not all primary stroke centers are capable of delivering endovascular care, emergency medical services are now tasked with routing such patients who have large vessel occlusions to facilities capable of delivering such therapies. There are patient specific and and emergency medical system issues to a decision to bypass a local primary stroke center in favor of transport to an comprehensive center. Few of the LVO identification tools have been validated by paramedics. We sought to describe the utility of the Los Angeles Motor Score (LAMS) and of other physical findings for predicting the presence of a LVO in a population of stroke code patients examined by paramedics and EMTs. Methods: We analyzed a convenience sample of stroke code patients presenting to a tertiary care center ED. Paramedics examined patients using the LAMS. Paramedics were also asked to assess for problems including leg weakness, visual disturbances, altered level of consciousness, and language abnormalities (dysarthria, aphasia). We calculated operating characteristics of a LAMS score of ≥ 4 and of a modification of the LAMS to include speech disturbance, and performed a stepwise logistical regression on the other potential physical exam elements that might predict large vessel occlusion. Results: A total of 332 subjects mean age 68 (±SD17), 53% female were examined by paramedics. One hundred forty (42%) had a stroke, and of these 71 (21%) had an LVO. A LAMS ≥ 4 identified stroke and large vessel occlusions with sensitivity of 28% and 38% and specificity of 95% and 92% respectively. Using LAMS of 1 to 3 with an abnormal speech test, 12 additional strokes and 8 LVOs were identified with resultant sensitivity and specificity of 36% and 94% and 49% and 89% for stroke and LVO respectively. Conclusion: Performed by paramedics and EMTs in an enriched stroke code population, the LAMS score can be used to identify LVOs with high specificity. More importantly, use of the modified LAMS results in an NPV of 87% with a PPV of 56%. This suggests that application of the modified rule would capture many cases of LVO while transporting few patients longer distances unnecessarily.