Specialist PrE-hospital rEDirection for ischaemic stroke thrombectomY (SPEEDY): study protocol for a cluster randomised controlled trial with included health economic and process evaluations.

backgroundOutcome from large vessel occlusion stroke can be significantly improved by time-critical thrombectomy but treatment is only available in regional comprehensive stroke centres (CSCs). Many patients are first admitted to a local primary stroke centre (PSC) and require transfer to a CSC, which delays treatment and decreases the chance of a good outcome. Access to thrombectomy might be improved if eligible patients could be identified in the prehospital setting and selectively redirected to a CSC. This study is evaluating a new specialist prehospital redirection pathway intended to facilitate access to thrombectomy. METHODS AND ANALYSIS: This study is a multicentre cluster randomised controlled trial with included health economic and process evaluations. Clusters are ambulance stations (or teams) which are work bases for ambulance practitioners. Intervention allocated ambulance practitioners use the Specialist PrE-hospital rEDirection for ischaemic stroke thrombectomY ('SPEEDY') pathway which comprises initiation according to specific criteria followed by contact with CSC staff who undertake a remote assessment to select patients for direct CSC admission. Control allocated ambulance practitioners continue to provide standard care which comprises admission to a local PSC and transfer to a CSC for thrombectomy if required. A co-primary outcome of thrombectomy treatment rate and time from stroke symptom onset to thrombectomy treatment will evaluate the impact of the pathway. Secondary outcomes include key aspects of emergency care including prehospital/hospital time intervals, receipt of other treatments including thrombolysis, and performance characteristics of the pathway. A broad population of all ambulance practitioner suspected and confirmed stroke patients across participating regions is being enrolled with a consent waiver. Data about SPEEDY pathway delivery are captured onto a study case record form, but all other data are obtained from routine healthcare records. Powered on a 'primary analysis population' (ischaemic stroke patients with pathway initiation criteria), 894 participants will detect an 8.4% difference in rate and data from 564 thrombectomy procedures will detect a 30 minute difference in time to treatment. The full study population is estimated to be approximately 80 000. Regression modelling will be used to examine primary and secondary outcomes in several analysis populations. The economic analyses will include cost-effectiveness and cost-utility analyses, and calculation of willingness to pay at a range of accepted threshold values. The process evaluation involves semi-structured interviews with professionals and patient/family members to explore views and experiences about the SPEEDY pathway. ETHICS AND DISSEMINATION: This study has ethical, Health Research Authority and participating NHS Trust approvals.Dissemination of study results will include presentations at national and international conferences and events, publication in peer-reviewed journals, and plain English summaries for patient/public engagement activities. TRIAL REGISTRATION NUMBER: ISRCTN77453332.