Background and purpose: The effects of early upright positioning in the acute phase of ischemic stroke on both blood pressure and functional outcome have not been previously examined.
Methods: Prospective investigation of mean arterial pressure, heart rate, and peripheral oxygen saturation in the supine, sitting, and (if achievable) active standing position 1, 2, and 3 days after an acute stroke was performed. Also investigated was the presence of a significant postural blood pressure rise and fall using orthostatic definitions and the relation to functional outcome after 3 months.
Results: One hundred sixty-seven patients were included (mean age, 68.5±15.2 years; median National Institutes of Health Stroke Scale, 7). Approximately 60% of the patients were able to stand. On average the mean arterial pressure increased when patients moved from the supine to sitting (Day 1: Δ 3.9 mm Hg; P<0.001) and from sitting to an active standing position (Day 1: Δ 4.6 mm Hg; P<0.001). Changes were most pronounced within the first 24 hours after a stroke. Blood pressure decreased significantly (fall) on standing in 13% of patients and increased significantly (rise) in 20% of the patients. The latter was independently associated with a favorable outcome (P=0.003). Moving to the standing position was accompanied by an increase of heart rate. No difference in oxygen saturation was observed in the various positions over the period of investigation.
Conclusions: We found that a significant blood pressure rise during early upright positioning in patients with acute stroke was independently associated with a favorable outcome. No contraindication to early mobilization was found in this study.