Pressure-induced skin lesions in pigs: reperfusion injury and the effects of vitamin E.
The pathogenesis of the development of pressure ulcers is still unclear. The aim of this study was to investigate the role of ischaemia and reperfusion in pressure-induced tissue necrosis in the trochanteric region in pigs. Pressure application was achieved with a newly developed computer-controlled pressure device. Histological examination showed damage in the subcutis and muscle tissue comparable with inflammation, extending in a vascular pattern beyond the area of pressure application. Electron-microscopic studies revealed neutrophil adherence to the capillary endothelium, which showed signs of injury. These observations were manifest two hours after the cessation of pressure. Pre-treatment with 500 mg vitamin E per day resulted in significantly less tissue damage compared with untreated animals. Pressure alone caused a significant decrease in reduced glutathione and total glutathione, suggesting oxidative stress. After pressure release there was a significant increase in hydrogen peroxide concentration, suggesting a decreased antioxidant protection. After pre-treatment with vitamin E, however, there was no increase of hydrogen peroxide. It is concluded that the early signs of necrosis after pressure application are concordant with typical ischaemia-reperfusion damage and this can be prevented in part by treatment with vitamin E. Prophylactic administration of vitamin E may influence the occurrence of pressure ulcers in humans undergoing elective surgery.
Houwing
R
R
Department of Dermatology, University Hospital Utrecht, The Netherlands.
Overgoor
M
M
Kon
M
M
Jansen
G
G
van Asbeck
B S
BS
Haalboom
J R
JR
D000818:Animals; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D009336:Necrosis; D003668:Pressure Ulcer / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D013552:Swine; D014810:Vitamin E / Q000627:therapeutic use*
D014810:Vitamin E