® DR R. Ackermann
One of the most fateful complications of immobile patients (paraplegia, condition after stroke, etc.) and those with peripheral circulatory disorders (diabetes, vascular disease) is the pressure ulcers (pressure sores).
A pressure ulcer is a serious, sometimes life-threatening disease with protracted course. The pressure ulcer is defined as damage to the skin caused by prolonged local pressure. It develops in several pathophysiological steps. Development of pressure ulcers (bedsores) Missing safety awareness (Paraplegia, diabetes, Polyneurophatie) Pressure of the body - back pressure of the mattress (Capillary pressure of 25-35mm Hg) Local hypoperfusion Oxygen deficiency Accumulation of toxic metabolites Dead skin cells Formation of ulcers sun When sitting or lying down, the human body exerts pressure on the bearing surface, which generates in turn rests on the skin area back pressure. The amount of back pressure results from the hardness of the supporting surface. In the arterial terminal vessels, the capillaries, the physiological pressure is 25 - 35 mmHg. Higher pressure is applied, the skin can tolerate short-term (up to 4 hours). But keeps the pressure for long periods in which capillaries are compressed, resulting in reduced blood flow and oxygen deficiency (hypoxia) leads in the affected skin area. In this incipient damage the body reacts with pain, pressure, which cause a change of position when healthy. In this case, even small movements sufficient to interrupt the duration of the action of pressure and to normalize the disturbed circulation again. This mechanism occurs spontaneously and is controlled by the sensitive nerve endings in the skin. One speaks of the protection sensitivity. Even in sleep does this protective mechanism, so that a healthy person does not develop pressure sore. In a number of diseases of this defense mechanism is impaired. Either the patient can not move (paralysis, loss of consciousness), or he does not feel the pain (sensory disturbance in nervous disorders, diabetes, or alcoholism) .. In these cases, no relief of the skin occurs, the reduced blood flow increases, the tissue damage progresses to pressure ulcers. What influence has now the system to the blood circulation of the overlying skin areas? Due to the pyramidal surface structure reduces the contact area estimated at a quarter or fifth of the total deck area. The pressure on the single-loaded areas on the pyramid tips will thereby inevitably. On the other hand, the areas of the skin between the pyramids are unloaded, the blood flow is not disturbed. Going now from the fact that the sleeping up to 60 times a night changing its position, it is independent of the protective reflex mechanisms described above ensures that it can never come to a critical hypoperfusion of the skin. On the contrary! The constant change of loading and unloading of the skin has a Blood circulation-promoting effect, which is similar to changes baths. If, in a tissue area for a time the blood supply impaired, it comes to removing the obstacle to a temporary excessive blood flow. This effect is regularly Extremities operations that were performed in a bloodless field, after opening the tourniquet to watch. The pyramidal structure of the surface BRW - contour lying area due to constant changing causes a pressure load circulatory promotion of the skin and subcutaneous tissue.