Measurement system for the evaluation of alternating pressure redistribution mattresses using pressure relief index and tissue perfusion – a preliminary study

Abstract

Clinicians who are selecting dynamic support surfaces such as alternating pressure redistribution mattresses (APRMs) for the prevention and treatment of pressure ulcers are faced with commercial literature that predominantly reports on magnitudes of interface pressures, rather than on additional parameters. The aim of this preliminary study was to generate a pressure relief index (PRI) to evaluate dynamic support surfaces using the magnitude of interface pressures as well as their duration. Data for generating a PRI were captured from 11 subjects on two different dynamic support surfaces using three different, arbitrarily selected, interface pressure thresholds. Tissue perfusion measurements were used to evaluate the reliability of the calculated PRI. The results demonstrate a good relationship (r=0.7) between PRI and tissue perfusion values. The generated PRI appears to be a reliable indicator of the recovery time allowed below a given interface pressure and is therefore a useful parameter for selecting appropriate dynamic support surfaces