The effects of small shifts in body weight on blood flow and interface pressure.

The purpose of this study was to (a) determine whether small shifts in body weight change pressure and blood flow under a bony prominence, and (b) identify the magnitude of change in blood flow and pressure under a bony prominence over time. Blood flow and interface pressure in two positions (lateral oblique/supine) with two small shifts in each position (thigh/rib cage) were evaluated over time in 50 nursing home residents. There was a significant decrease in interface pressure under the trochanter through the small shifts intervention, F = 5.36, p < .01. There was a significant decrease in interface pressure, F = 3.90, p < .05, and a significant increase in blood flow, F = 4.85, p < .05, under the sacrum through the small shifts intervention. Blood flow and interface pressure did not change significantly over time.