A theory of interstitial fluid motion and its implications for capillary exchange

A nonlinear theory of interstitial fluid motion is presented in which the hydrodynamic conductivity and porosity of the tissue are regarded as arbitrary, but known, functions of interstitial fluid pressure. A previous study of capillary-tissue fluid exchange is extended using the more general theory for fluid flow in the surrounding tissue. Simplifications in the mathematical problem are made on the basis of results obtained in the earlier study, and perturbation techniques are used to obtain an asymptotic solution which is valid for most conditions of normal and pathological interest.