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 theprevention and treatment of pressure ulcers are faced with commercial literature that predominantly reports on magnitudes ofinterface pressures, rather than on additional parameters. The aim of this preliminary study was to generate a pressure reliefindex (PRI) to evaluate dynamic support surfaces using the magnitude of interface pressures as well as their duration. Data forgenerating a PRI were captured from 11 subjects on two different dynamic support surfaces using three different, arbitrarilyselected, 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 areliable indicator of the recovery time allowed below a given interface pressure and is therefore a useful parameter for selectingappropriate dynamic support surfaces