Basic research Effects on interface pressure and tissue oxygenation under ischial tuberosities during the application of an alternating cushion Sandra Arias a,1 , Eladio Cardiel a,1 , Laura Garay b , Hiromi Sanada c , Taketoshi Mori d , Hiroshi Noguchi d , Gojiro Nakagami c , Pablo Rogeli a, * a Center for Research and Advanced Studies of the National Polytechnic Institute, Electrical Engineering Department/Bioelectronics Section, Av. IPN 2508 Col. San Pedro Zacatenco, Mexico D.F., C.P. 07360, Mexico b National Polytechnic Institute, UPIITA, Av. IPN 2580 La Laguna Ticoman, 07340, Me´xico D.F., Mexico c Graduate School of Medicine, The University of Tokyo, Department of Gerontological Nursing/Wound Care Management, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan d Graduate School of Medicine, The University of Tokyo, Department of Life Support Technology (Molten), 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan KEYWORDS Perfusion; Dynamic cushion; Pressure ulcer; Wheelchair user; Stimulation Abstract Pressure ulcers are hazardous to people with diminished sensory and motor functions who remain in the same position for a long time. An important reason for the occurrence of pressure ulcers is the inability of wheelchair users to make postural changes by themselves with no appropriate method of pressure release. In this study, we researched the effects of applying an air cell inflate- deflate alternating sequence cushion prototype to relieve pressure from tissue loaded areas. Moreover, the hypothesis that the alternating sequence could stimu- late blood reperfusion in loaded tissues and redistribute interface pressure on sup- port area was also tested. Ten healthy volunteers were recruited to try the prototype cushion for 65 min of continuous loading; 5 min on static mode and 60 min on alternating mode. This study was conducted on healthy people because * Corresponding author. Tel.: þ52 5557473800x6201. E-mail addresses: sarias@cinvestav.mx (S. Arias), ecardiel@cinvestav.mx (E. Cardiel), lgaray@ipn.mx (L. Garay), hsanada-tky@ umin.ac.jp (H. Sanada), tmoriics-tky@umin.ac.jp (T. Mori), hnogu-tky@umin.ac.jp (H. Noguchi), gojiron-tky@umin.ac.jp (G. Nakagami), pablo.rogeli@cinvestav.mx (P. Rogeli). 1 Tel.: þ52 5557473800x6201. http://dx.doi.org/10.1016/j.jtv.2015.05.002 0965-206X/ª 2015 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved. Journal of Tissue Viability (2015) 24, 91e101 www.elsevier.com/locate/jtv