Experimental non-controlled, non-randomized study in two phases: preclinical and clinical. The first phase, will be conducted in healthy volunteers and the second, in patients at risk for impaired skin integrity. Vascular flow, tissue oxygenation and local temperature in areas at risk of pressure ulcers by Doppler laser will be evaluated in subjects lying on a capacitive surface to measure pressure with 10,249 points of measurement, which will be subject to different body systems to generate different levels of pressure and monitor changes in tissue perfusion and oxygenation up to 4 hours, to know the implications for repositioning interventions in patients at risk.