Departments of Medicine and Neurology, Melbourne Brain Centre at The Royal Melbourne Hospital (H.Z., L.C., J.L.N., C.W., F.A., F.N., P.J.M., M.W.P., N.Y., S.M.D., B.C.V.C.), University of Melbourne, Australia.
Ambulance Victoria, Melbourne, Australia (H.Z., K.S., S.B., M.S., C.F.B., F.N., N.Y., B.C.V.C.).
Stroke. 2021 Jan;52(1):70-79. doi: 10.1161/STROKEAHA.120.031467. Epub 2020 Dec 22.
Severity-based assessment tools may assist in prehospital triage of patients to comprehensive stroke centers (CSCs) for endovascular thrombectomy (EVT), but criticisms regarding diagnostic inaccuracy have not been adequately addressed. This study aimed to quantify the benefits and disadvantages of severity-based triage in a large real-world paramedic validation of the Ambulance Clinical Triage for Acute Stroke Treatment (ACT-FAST) algorithm.
Ambulance Victoria paramedics assessed the prehospital ACT-FAST algorithm in patients with suspected stroke from November 2017 to July 2019 following an 8-minute training video. All patients were transported to the nearest stroke center as per current guidelines. ACT-FAST diagnostic accuracy was compared with hospital imaging for the presence of large vessel occlusion (LVO) and need for CSC-level care (LVO, intracranial hemorrhage, and tumor). Patient-level time saving to EVT was modeled using a validated Google Maps algorithm. Disadvantages of CSC bypass examined potential thrombolysis delays in non-LVO infarcts, proportion of patients with false-negative EVT, and CSC overburdening.
Of 517 prehospital assessments, 168/517 (32.5%) were ACT-FAST positive and 132/517 (25.5%) had LVO. ACT-FAST sensitivity and specificity for LVO was 75.8% and 81.8%, respectively. Positive predictive value was 58.8% for LVO and 80.0% when intracranial hemorrhage and tumor (CSC-level care) were included. Within the metropolitan region, 29/55 (52.7%) of ACT-FAST-positive patients requiring EVT underwent a secondary interhospital transfer. Prehospital bypass with avoidance of secondary transfers was modeled to save 52 minutes (95% CI, 40.0-61.5) to EVT commencement. ACT-FAST was false-positive in 8 patients receiving thrombolysis (8.1% of 99 non-LVO infarcts) and false-negative in 4 patients with EVT requiring secondary transfer (5.4% of 74 EVT cases). CSC bypass was estimated to over-triage 1.1 patients-per-CSC-per-week in our region.
The overall benefits of an ACT-FAST algorithm bypass strategy in expediting EVT and avoiding secondary transfers are estimated to substantially outweigh the disadvantages of potentially delayed thrombolysis and over-triage, with only a small proportion of EVT patients missed.
基于严重程度的评估工具可能有助于将患者分诊至综合卒中中心（CSC）进行血管内取栓治疗（EVT），但关于诊断准确性的批评尚未得到充分解决。本研究旨在通过对救护车临床快速评估急性卒中治疗（ACT-FAST）算法进行大型真实世界的护理人员验证，量化基于严重程度的分诊的优势和劣势。
维州救护车护理人员在 2017 年 11 月至 2019 年 7 月期间，观看了 8 分钟的培训视频后，对疑似卒中的患者进行了预分诊评估。所有患者均按照现行指南转运至最近的卒中中心。将 ACT-FAST 的诊断准确性与医院影像学检查结果进行比较，以评估大血管闭塞（LVO）和 CSC 级护理（LVO、颅内出血和肿瘤）的需求。使用经过验证的谷歌地图算法对 EVT 前的患者节省时间进行建模。通过分析非 LVO 梗死患者潜在的溶栓延迟、假阴性 EVT 患者比例以及 CSC 负担过重，检查了 CSC 绕过的缺点。
在 517 例预分诊评估中，168/517（32.5%）为 ACT-FAST 阳性，132/517（25.5%）为 LVO。ACT-FAST 对 LVO 的敏感性和特异性分别为 75.8%和 81.8%。当包括颅内出血和肿瘤（CSC 级护理）时，LVO 的阳性预测值为 58.8%，而 80.0%为 LVO 阳性和颅内出血和肿瘤（CSC 级护理）。在大都市区内，29/55（52.7%）需要 EVT 的 ACT-FAST 阳性患者进行了二次院内转院。通过避免二次转院的预分诊绕过，预计可将 EVT 开始前的时间缩短 52 分钟（95%CI，40.0-61.5）。8 例接受溶栓治疗的患者（99 例非 LVO 梗死患者的 8.1%）出现 ACT-FAST 假阳性，4 例需要二次转院的 EVT 患者（74 例 EVT 病例的 5.4%）出现假阴性。在本地区，估计 CSC 绕过策略每 CSC 每周可能会过度分诊 1.1 例患者。
ACT-FAST 算法绕过策略在加快 EVT 速度和避免二次转院方面的总体优势，估计大大超过了潜在的溶栓延迟和过度分诊的劣势，只有一小部分 EVT 患者被漏诊。
