The Management of Pressure and Other External Factors in the Prevention of Ischemic Ulcers

Abstract

The primary external causes of ischemic ulcers or bedsores are (a) pressure, (b) abrasion with associated shear deformations, (c) moisture, and (d) lack of cleanness. These disturbances perturb the microcirculation and inhibit the mass transport necessary to support local metabolism. These external factors can be managed through engineering analysis and design. A technique has been developed to measure the pressure distributions between the body and various support systems without perturbing the pressure distribution using a thin, pliable, pneumatic-cell, pressure-sensor. Data are presented for several existing support devices, and design requirements have been determined for an external support system for the chronically ill and debilitated which will periodically relieve and redistribute external pressures and prevent the formation (and aid in treatment) of ischemic ulcers. The design is based primarily on the physiologically allowable time-at-pressure data and the anatomy.