Repositioning mattress: how a lateral tilt position reshapes the prevention of pressure ulcers in bedridden patients.

Pressure ulcers have been part of tissue damage without effectiveness in medical, surgical, and intensive care units. This study aims to focus on developing lateral tilt positions for effective pressure ulcer relief for bedridden patients. A repositioning mattress was placed in the side-lying left lateral tilt position (15°, 30°, 45°), sheering (0.680, 1.323, 1.870), interface pressure (2.550, 2.290, 2.830), and placed at 1.5 m long piece of polyethylene rubber. The design strength was set at 6000 N and 2100 mm x 1105 mm (${\sigma }_{t,0,d}$ = 42, ${\sigma }_{c,0,d}$ = 34). The design shows the greatest supine position at 30°, 1.323, 2.290, pressure load ($\Delta p_0$ = 1.125 (1820) $\approx$ 2050 psi, $\Delta p_{3000}$ = 1.125 (620) $\approx$ 700 psi), tensile stress (${\sigma }_{t,0,d}$ (MPa) = 42), compressive stress (${\sigma }_{c,0,d}$ (MPa) = 34), and FOS (${\sigma }_{t,0,d}$ = 42, ${\sigma }_{c,0,d}$ = 34). The factor of safety illustrated that the 30° lateral tilt position is more consistent in repositioning for pressure ulcer prevention compared to the supine-to-tilt region. Further, an application of repositioning mattresses was developed to test in bedridden patients with tissue ulcers in nursing homes.