Interstitial Compliance Research Articles

Compliance of the interstitial space and the measurement of tissue pressure.

volume. In the past, most physiologists have considered the compliance of the interstitial spaces to remain almost constant at different levels of inteistitial fluid pressure, but recent studies indicate that interstitial space compliance changes 25 fold or more in different interstitial fluid pressure ranges. These recent studies on the compliance of the interstitial space have been based on the development of new methods for measuring interstitial fluid pressure, methods that give considerably different values for interstitial fluid pressure than had formerly been believed. Interstitial Fluid Pressure and Its Measurement Measurement o[ Total Tissue Pressure. In the past, interstitial fluid pressure has been measured by two principal methods. The first of these has been to insert a minute needle into the tissue and then to measure the pressure required to cause the minutest amount of fluid flow from the tip of the needle into the tissue space. The second method has been to insert a balloon into a tissue and to measure the least amount of pressure required to initiate the slightest inflation of the balloon against the pressure of the tissue. In using both of these methods, the measured pressures have ranged, in usual subcutaneous connective tissue, between approximately A- 1 and -~ 4 mm Hg. Unfortunately, it recently became apparent that these two methods probably measure not the interstitial fluid pressure but a combination of this pressure and the pressure of solid elements of the tissue as well because both of the methods require positive displacement of both the fluid in the tissue and the solid elements. Therefore, the measured pressures almost certainly represent total

The Partitioning of Body Water in Amphibia

The Partitioning of Body Water in Amphibia