Comparison of prehospital stroke assessment scales for acute ischemic stroke with large vessel occlusion within six hours of onset: A single-center study in Eastern Taiwan.

Abstract

Objectives: In Taiwan, acute ischemic stroke (AIS) with large vessel occlusion (LVO) remains a significant health concern. Reperfusion therapy is more effective if the patient arrives at the medical center within the early time window, emphasizing the importance of prehospital stroke assessment to identify LVO and rapid transfer. This study focused on Eastern Taiwan, where the Hualien Tzu Chi Hospital is the sole comprehensive stroke center. We compared different prehospital stroke assessment scales in identifying LVO.

Materials and methods: We reviewed 598 patients with acute stroke admitted to our hospital's emergency department between April 1, 2021, and March 31, 2022. Of these, 110 AIS cases presenting within 6 h of symptom onset were retrospectively analyzed using the medical records and National Institute of Health Stroke Scale (NIHSS) scores to evaluate the efficacies of prehospital stroke scales, including our institution's Tzu Chi Stroke Severity Scale and its modified version. LVO was defined as occlusion of the anterior cerebral artery, middle cerebral artery, and its main branches, intracranial carotid arteries, and vertebrobasilar arteries.

Results: Among 110 patients, 39.1% had LVO, which showed a higher mortality rate and prevalence of atrial fibrillation. LVO had higher NIHSS scores and longer hospital stays. The Vision Aphasia Neglect (VAN) Scale and Modified Tzu Chi Stroke Severity Scale showed the highest sensitivity, with the latter also exhibiting the highest sensitivity for posterior circulation LVO.

Conclusion: The VAN and the modified Tzu Chi Stroke Severity Scale offer comparable sensitivity for detecting LVO in the prehospital setting. Our study supports the adoption of the modified Tzu Chi scale in the regional emergency medical service transfer algorithm for LVO detection for timely intervention.