Emergency medical dispatchers' ability to identify large vessel occlusion stroke during emergency calls.

BACKGROUND: In acute ischemic stroke, conjugated eye deviation (CED) is an evident sign of cortical ischemia and large vessel occlusion (LVO). We aimed to determine if an emergency dispatcher can recognise LVO stroke during an emergency call by asking the caller a binary question regarding whether the patient's head or gaze is away from the side of the hemiparesis or not. Further, we investigated if the paramedics can confirm this sign at the scene. In the group of positive CED answers to the emergency dispatcher, we investigated what diagnoses these patients received at the emergency department (ED). Among all patients brought to ED and subsequently treated with mechanical thrombectomy (MT) we tracked the proportion of patients with a positive CED answer during the emergency call. METHODS: We collected data on all stroke dispatches in the city of Tampere, Finland, from 13 February 2019 to 31 October 2020. We then reviewed all patient records from cases where the dispatcher had marked 'yes' to the question regarding patient CED in the computer-aided emergency response system. We also viewed all emergency department admissions to see how many patients in total were treated with MT during the period studied. RESULTS: Out of 1913 dispatches, we found 81 cases (4%) in which the caller had verified CED during the emergency call. Twenty-four of these patients were diagnosed with acute ischemic stroke. Paramedics confirmed CED in only 9 (11%) of these 81 patients. Two patients with positive CED answers during the emergency call and 19 other patients brought to the emergency department were treated with MT. CONCLUSION: A small minority of stroke dispatches include a positive answer to the CED question but paramedics rarely confirm the emergency medical dispatcher's suspicion of CED as a sign of LVO. Few patients in need of MT can be found this way. Stroke dispatch protocol with a CED question needs intensive implementation.

Safety and Outcomes of Thrombectomy in Ischemic Stroke With vs Without IV Thrombolysis.

OBJECTIVE: To test the hypothesis that IV thrombolysis (IVT) treatment before endovascular thrombectomy (EVT) is associated with better outcomes in patients with anterior circulation large artery occlusion (LAO) stroke, we examined a large real-world database, the Safe Implementation of Treatment in Stroke-International Stroke Thrombectomy Register (SITS-ISTR). METHODS: We identified centers recording ≥10 consecutive patients in the SITS-ISTR, with at least 70% available modified Rankin Scale (mRS) scores at 3 months during 2014 to 2019. We defined LAO as intracranial internal carotid artery, first and second segment of middle cerebral artery, and first segment of anterior cerebral artery. Main outcomes were functional independence (mRS score 0-2) and death at 3 months and symptomatic intracranial hemorrhage (SICH) per modified SITS-Monitoring Study. We performed propensity score-matched (PSM) and multivariable logistic regression analyses. RESULTS: Of 6,350 patients from 42 centers, 3,944 (62.1%) received IVT. IVT + EVT-treated patients had less frequent atrial fibrillation, ongoing anticoagulation, previous stroke, heart failure, and prestroke disability. PSM analysis showed that IVT + EVT-treated patients had a higher rate of functional independence than patients treated with EVT alone (46.4% vs 40.3%, p < 0.001) and a lower rate of death at 3 months (20.3% vs 23.3%, p = 0.035). SICH rates (3.5% vs 3.0%, p = 0.42) were similar in both groups. Multivariate adjustment yielded results consistent with PSM. CONCLUSION: Pretreatment with IVT was associated with favorable outcomes in EVT-treated LAO stroke in the SITS-ISTR. These findings, while indicative of international routine clinical practice, are limited by observational design, unmeasured confounding, and possible residual confounding by indication. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that IVT before EVT increases the probability of functional independence at 3 months compared to EVT alone.

The Finnish Prehospital Stroke Scale Detects Thrombectomy and Thrombolysis Candidates-A Propensity Score-Matched Study.

BACKGROUND: Prehospital stroke triage is challenged by endovascular treatment for large vessel occlusion (LVO) being available only in major stroke centers. Conjugate eye deviation (CED) is closely related to LVO, whereas common stroke signs (face-arm-leg-speech-visual) screen stroke. We hypothesized that combining CED with common stroke signs would yield a prehospital stroke scale for identifying both LVO and stroke in general. METHODS AND RESULTS: We retrospectively analyzed consecutive patients (n = 856) with prehospital Code Stroke (recanalization candidate). The National Institutes of Health Stroke Scale (NIHSS) and computed tomography were administered to patients on arrival. Computed tomography angiography was performed on patients with NIHSS score of 8 or greater and considered to benefit from endovascular treatment. With random forest analysis and deviance analysis of the general linear model we confirmed the superiority of the NIHSS "Best Gaze" over other NIHSS items in detecting LVO. Based on this and commonly used stroke signs we presented the Finnish Prehospital Stroke Scale (FPSS) including dichotomized face drooping, extremity weakness, speech difficulty, visual disturbance, and CED. FPSS detected LVO with a sensitivity of 54%, specificity of 91%, positive predictive value of 48%, negative predictive value of 93%, and likelihood ratio of 6.2. CONCLUSIONS: Based on CED and universally used stroke signs, FPSS recognizes stroke in general and additionally, LVO as a stroke subtype comparably to other scales intended to detect LVO only. As the FPSS items are dichotomized, it is likely to be easy for emergency medical services to implement.