Feasibility and Challenges of Ambulance-Delivered Blood Pressure Lowering in Hyperacute Stroke

作者：Xue Gao, Chen Chen, Yapeng Lin, Jie Yang, Gang Li, Lili Song, Craig S. Anderson, Feifeng Liu, Menglu Ouyang, for the INTERACT4 study group and investigators · 发表于：Cerebrovascular Diseases · 年份：2026 · DOI：10.1159/000552172 · 研究领域：Acute Ischemic Stroke Management、Health Policy Implementation Science、Simulation-Based Education in Healthcare

INTRODUCTION: Stroke trials conducted in prehospital settings face inherent complexities in patient screening, timely intervention delivery, and outcome assessment. The INTEnsive ambulance-delivered blood pressure Reduction in hyper-acute stroke Trial (INTERACT4) investigated the effect of prehospital blood pressure (BP) lowering initiated within 2 h of symptom onset in suspected acute stroke across multiple sites in China. This process evaluation aimed to examine implementation outcomes and contextual mechanisms influencing delivery. METHODS: A mixed-methods approach with a convergent parallel design. Quantitative data on fidelity, dose, and reach were obtained from case report forms and monitoring logs, including protocol deviations and BP target achievement. Qualitative data on acceptability, appropriateness, and adoption were collected through semi-structured interviews with ambulance and hospital staff from eight sampled hospitals, and a focus group discussion with project implementers. Data were analyzed descriptively and thematically, guided by the Medical Research Council complex intervention framework for process evaluation and normalization process theory. RESULTS: A total of 34 participants (19 ambulance staff and 15 hospital doctors) across 8 sites were interviewed. Fidelity was generally acceptable, with nearly 90% of eligible patients receiving the first urapidil dose. Dose achievement was modest, with 31.7% of patients achieving the prehospital systolic BP targ...