Zusammenfassung
Die einzig sinnvolle und effektive Therapie bei peripheren Ödemen ist die externe Kompressionstherapie. Die Kenntnis der wenigen physikalischen Gesetzmäßigkeiten, die bei der Kompressionstherapie gelten, ebenso wie die Kenntnis die Materialkunde der Kompressionsmittel sind zwingende Voraussetzung für den sachgemäßen und erfolgreichen Einsatz der physikalischen Therapie peripherer und fokaler Ödeme. Die physikalische Grundlage der Kompressionstherapie ist die Gleichung nach Laplace. Die Konsequenzen aus dieser Gleichung und die sich daraus abgrenzbaren unterschiedlichen Druckarten und Druckcharakteristiken sollen erläutert werden.
Summary
Under physiological conditions, peripheral water balance is regulated on the one hand by a relatively stable distribution of free body water in the various, well-defined fluid compartments, and on the other by an equilibrium between the outflow and inflow of fluid from and into the intravasal space. For a patient of normal weight, the peripheral filtrate under physiological conditions is likely to be approx. 8 litres per 24 hours. This balance between filtration and absorption under steady-state conditions is known under the term the Starling equilibrium. This corresponds to a balance between the physical forces acting in the area of the capillaries – hydrostatic pressure, colloid osmotic pressure and tissue pressure – as can be represented in a classic diagram.
In simplified terms, peripheral oedema can be attributed to a local disturbance of the Starling equilibrium in the sense of a predominance of filtration in relation to absorption. In the terminology of physics, this means that the (trans-mural) pressure gradient runs from the intravasal compartment into the interstitial compartment. If these gradients can be reversed, then the equilibrium is shifted towards absorption. This gradient reversal is the principle behind the physical treatment of peripheral oedema. Through a targeted, externally applied pressure (compression) on the oedematous tissue, the transmural pressure should be shifted towards absorption.
The physical basis of compression therapy is the Laplace equation: D = S/r. With regard to pressure distribution under external compression to the extremities, a distinction is drawn between concentric compression and excentric compression.
Schlüsselwörter
Ödeme - Ödemtherapie - Laplace-Gleichung - Konzentrische Kompression - Exzentrische Kompression
Keywords
Oedemas - Oedema therapy - Laplace equation - concentric compression - excentric compression
