title: Effects on interface pressure and tissue oxygenation under ischial tuberosities during the application of an alternating cushion.
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 stimulate blood reperfusion in loaded tissues and redistribute interface pressure on support 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 their sensitivity allowed them to state clearly and in detail, in a feedback questionnaire, any discomfort experienced with the use of our cushion. In order to address our hypothesis, interface pressure, and bilateral ischial oxygenated and deoxygenated hemoglobin were measured. After applying the alternating cushion, the interface pressure was redistributed over a larger contact area. Besides, blood perfusion was improved according to increments in oxygenated hemoglobin and decrements in deoxygenated hemoglobin of ischial regions during loaded condition. Feedback questionnaire showed that the participants did not feel pain or discomfort using the alternating cushion. The overall results showed positive effects on healthy tissue which has encouraged us to design a study involving subjects who use wheelchairs for mobility.
authors.affiliation: 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. Electronic address: sarias@cinvestav.mx.
authors.forename: Sandra
authors.initials: S
authors.lastname: Arias
authors.affiliation: 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. Electronic address: ecardiel@cinvestav.mx.
authors.forename: Eladio
authors.initials: E
authors.lastname: Cardiel
authors.affiliation: National Polytechnic Institute, UPIITA, Av. IPN 2580 La Laguna Ticoman, 07340, México D.F., Mexico. Electronic address: lgaray@ipn.mx.
authors.forename: Laura
authors.initials: L
authors.lastname: Garay
authors.affiliation: 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. Electronic address: hsanada-tky@umin.ac.jp.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Sanada
authors.affiliation: Graduate School of Medicine, The University of Tokyo, Department of Life Support Technology (Molten), 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan. Electronic address: tmoriics-tky@umin.ac.jp.
authors.forename: Taketoshi
authors.initials: T
authors.lastname: Mori
authors.affiliation: Graduate School of Medicine, The University of Tokyo, Department of Life Support Technology (Molten), 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan. Electronic address: hnogu-tky@umin.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Noguchi
authors.affiliation: 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. Electronic address: gojiron-tky@umin.ac.jp.
authors.forename: Gojiro
authors.initials: G
authors.lastname: Nakagami
authors.affiliation: 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. Electronic address: pablo.rogeli@cinvestav.mx.
authors.forename: Pablo
authors.initials: P
authors.lastname: Rogeli
mesh_terms: D000328:Adult; D002081:Buttocks; D005260:Female; D006801:Humans; D007512:Ischium / Q000502:physiology*; D008297:Male; D010100:Oxygen / Q000378:metabolism*; D011312:Pressure; D003668:Pressure Ulcer / Q000517:prevention & control
chemical_list: D010100:Oxygen
keywords: Dynamic cushion; Perfusion; Pressure ulcer; Stimulation; Wheelchair user