Primary Outcome Measures:
- Reduction in microvascular blood flow in supine position [ Time Frame: 72 hours post stroke ]
Microvascular blood flow will be measured at 24, 48, and 72 hours post stroke, with the head of bed at 30, 15, and 0 deg (supine). Current clinical practice is to lower the head of bed to the supine position to increase blood flow.
Arterial ischemic stroke (AIS) affects about 2 children per 100,000 per year and is one of the top 10 causes of mortality in children. After stroke, there is a disturbance in cerebral blood flow (CBF) autoregulation, and changes in head position may change CBF. Currently, practice at CHOP is to keep the head of bed (HOB) of a child with AIS flat for 24 hours; however, there is no evidence that this practice is efficacious in children. Furthermore, maintaining a child supine for 24 hours is uncomfortable for the child and is often unenforceable in younger children. This study will use a noninvasive optical technique to measure CBF as HOB position is changed to assess the effectiveness of head of bed position in increasing CBF in children with acute arterial ischemic stroke.
The primary objectives are to determine the difference in CBF at HOB flat (0 degrees) and HOB at +30 degrees in healthy children and in children with AIS. The secondary objectives are to examine CBF in healthy children and in children with AIS at other HOB angles (0, +15, and +30 degrees) compared to the CBF at HOB 0 degrees and to determine if the position that maximizes CBF varies over time from stroke onset.