Related Experiment Video
Updated: Mar 16, 2026

Contrast Enhanced Ultrasound Imaging for Assessment of Spinal Cord Blood Flow in Experimental Spinal Cord Injury
Published on: May 7, 2015
Blood flow responses over sacrum in nursing home residents during one hour bed rest
Ulrika Källman1,2, Sara Bergstrand3, Anna-Christina Ek3
1Department of Medical and Health Sciences, Division of Nursing Linköping University, Linköping, Sweden. ulrika.kallman@vgregion.se.
Objectives:
To describe individual BF responses in a nursing home resident population for one-hour periods of bed rest.
Methods:
BF was measured for one hour over the sacrum in 0° supine position and 30° supine tilt position in 25 individuals aged 65 y or older while lying on a pressure-redistributing mattress. Measurements were made at three tissue depths (1, 2, and 10 mm) using the noninvasive optical techniques, LDF and PPG.
Results:
Eleven participants had a PIV response at 1 mm depth in both positions and seven participants had a lack of this response at this depth and positions. The BF response at 1 mm depth appeared immediately and remained over, or below, baseline for the entire 60 min of loading in both positions. These BF patterns were also seen in deeper tissue layers.
Conclusions:
The cutaneous BF response among the nursing home residents was distinct, appeared early, and remained during the one hour of loading.
Related Concept Videos
Sites for measuring blood pressure
The Brachial Artery: Primary Site for Blood Pressure Measurement
Autoregulation of Blood Flow
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation....

