On the pathogenesis of bedsores. Skin blood flow cessation by external pressure on the back.
This paper is devoted to elucidation of the question: Which external pressure is required to stop skin blood flow at the skin - support interface in humans lying on the back in the supine position? Cessation of blood flow was recorded as cessation of washout of an intracutaneous depot of 131I-antipyrine mixed with histamine. The external pressure was measured by a small airfilled plastic cushion connected to a mercury manometer. In 11 normal subjects, eight patients with hypertension and seven patients with tetra- or paraplegia the "flow cessation external pressure" (FCEP) was strongly correlated to the auscultatory brachial mean blood pressure (p less than or equal to 0.001). The difference mean blood pressure - FCEP was on average 4 mmHg (range (-11) - (+20) mmHg) and there was no significant difference between the three groups studied. Thus external pressure exceeding the actual mean blood pressure will stop skin circulation.
D000328:Adult; D000368:Aged; D001794:Blood Pressure; D006801:Humans; D008875:Middle Aged; D011312:Pressure / Q000009:adverse effects; D003668:Pressure Ulcer / Q000209:etiology*; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply*