Supplementary Material for: Trendelenburg Positioning in Large Vessel Ischaemic Stroke: A Pre-Post Observational Study Using Propensity Score Matching

<b><i>Background:</i></b> Along with pharmacological and mechanical recanalization, improving cerebral perfusion through the recruitment of collateral vessels during the acute phase of ischaemic stroke (IS) is a clinical challenge. Our objective was to assess the effectiveness and safety of Trendelenburg positioning (TP), a procedure intended to increase cerebral blood flow, on the outcome of IS. <b><i>Methods:</i></b> Two cohorts of patients with an acute supratentorial IS related to a large artery occlusion were compared. In the first cohort (<i>n</i> = 119), we used standard positioning (0 to +30°); in the second cohort (<i>n</i> = 90), we used TP (0 to –15°). The primary outcome measure was the improvement of National Institutes of Health Stroke Scale (NIHSS) score between admission and day 2. Factors associated with an improvement ≥4 points of NIHSS score were assessed using multiple logistic regression and propensity score (PS) matching analyses. <b><i>Results:</i></b> TP was significantly associated with a greater improvement of NIHSS score within 48 h following stroke onset (4.0 ± 5.7 vs. 1.8 ± 5.9, <i>p</i> = 0.011) but also at discharge (<i>p</i> = 0.005). Multiple logistic regression analysis suggested that TP was an independent predictor of early neurological improvement (adjusted OR 1.81, 95% CI 1.00–3.27) in a model controlling recanalization and haemoglobin level. In addition, PS matching analysis confirmed the possible effectiveness of TP (unadjusted OR 1.99, 95% CI 1.04–3.82), especially in male subjects. The effect of TP was more pronounced in patients with admission mean arterial blood pressure ≥100 mm Hg, those exhibiting a good collateral vessel network on admission CT-angiography or experiencing an effective recanalization. Furthermore, TP was not associated with life-threatening complications. <b><i>Conclusion:</i></b> TP could be an effective and safe strategy in patients with large IS resulting from the proximal occlusion of a large vessel.