Experimental seat for the study of the effects of random pneumatic stimulation for the prevention of pressure ulcers

The design of an experimental seat to evaluate the effects of random movements of its flexible base on the blood circulation of critical areas submitted to pressure by the body weight is presented. Focused studies, related to subjects that remain seated for long periods of time in a wheelchair and that is prone to the formation of pressure ulcers, have reported that pressure ulcers are produced by ischemic disorders. The evaluation system is based on a seat with a flexible surface made of neoprene affixed to a wood box. The set forms a chamber to which air under pressure is injected by different inputs. The air enters into the chamber following a random pattern and generating movements on the neoprene seat. The evaluation of the seat was made with five subjects, without problems of pressure ulcers, to determine changes in pressure and temperature in the high risk zones, as they are the right and left ischial tuberosities. Both pressure and temperature parameters are considered indicators of the state of the blood circulation in the zones of study. Pressure variations that induce movement in the zones of risk were observed in the present work. This random pattern of movements generated decrements until secure pressures and increments of the local temperature, which suggests an improvement in the blood circulation in the zone of risk.