Optimal Head-of-Bed Positioning before Thrombectomy in Large Vessel Occlusion Stroke: A Randomized Clinical Trial

Importance: Small studies show that 0° head positioning of patients with large vessel occlusion (LVO) stroke improves penumbral blood flow and clinical stability. Understanding whether 0° head position maintains clinical stability would allow for optimal patient positioning before thrombectomy. Objective: To determine superiority of 0° over 30° head positioning at maintaining clinical stability in patients with LVO before thrombectomy. Design, Setting, and Participants: This was a prospective randomized clinical trial with blinding to study enrollment/end points conducted from May 2018 to November 2023. There were 3 planned interim analyses, and the study was conducted at certified thrombectomy hospitals in the US. Included in this analysis were consecutive consenting individuals with computed tomography (CT) angiography-positive anterior or posterior LVO who were candidates for thrombectomy (baseline mRS 0-1) and had viable penumbra (CT perfusion or Alberta Stroke Program Early Computed Tomography Score ≥6) within 24 hours of stroke onset. Enrollment of systemic thrombolysis more than 15 minutes from consent was discouraged to prevent confounding of head position effects; in addition, patients with disabilities who lacked a legal representative could not participate due to lack of consent. Interventions: Randomization to 0° or 30° head positioning with monitoring every 10 minutes using the National Institutes of Health Stroke Scale (NIHSS) until movement to a catheterization table. Main Outcome and Measures: The primary outcome was worsening of 2 or more NIHSS points before thrombectomy. Safety outcomes included severe neurologic deterioration (worsening ≥4 NIHSS points) before thrombectomy, hospital-acquired pneumonia (HAP) during hospitalization, and all-cause death within 3 months. Results: Planned enrollment included 182 patients. Before data and safety monitoring board study closure, a total of 92 patients (mean [SD] age, 66.6 [14.4] years; 48 male [52.2%]) were randomized: 45 patients to the group with 0° head positioning and 47 patients to the group with 30° head positioning. Patient characteristics were similar between groups; however, patients with head position at 30° experienced worsening on the NIHSS of 2 points or more, whereas patients with head position at 0° showed score stability (hazard ratio [HR], 34.40; 95% CI, 4.65-254.37; P <.001). One patient with 0° head positioning and 20 patients with 30° head positioning experienced worsening on the NIHSS of 4 points or more during positioning (HR, 23.57; 95% CI, 3.16-175.99; P =.002). No patients developed HAP; all-cause death occurred in 2 patients (4.4%) in the 0° group, compared with 10 patients (21.7%; P =.03) in the 30° group. Conclusions and Relevance: Results suggest that 0° head positioning for patients with acute LVO was a protective maneuver to maintain clinical stability in the prethrombectomy phase while awaiting definitive treatment.