Studies of Gas and Electrolyte Equilibria in the Blood

Abstract

This paper has for its purpose the presentation of data obtained from the analysis of blood serum and transudates from human subjects, and an examination of these data to determine whether the distribution of electrolytes in these systems is adequately defined by the laws first stated by Willard Gibbs, afterwards elaborated and tested by F. G. Donnan, and lately applied to protein solutions by Jacques Loeb. Van Slyke, Wu, and McLean showed in 1923 that the unequal distribution of bicarbonate and chloride ions between the serum and erythrocytes of horse blood, equilibrated at fixed CO2 tensions, was in harmony with the ratios predicted by the GibbsDonnan law. Calculations made at that time from the data of Loeb, Atchley, and Palmer of the distribution of electrolytes between serum and transudates suggested that these were systems which were in approximate equilibrium and to which the Donnan law could be applied. Except in the case of the chloride ratios, however, discrepancies of considerable magnitude existed between the distribution found by analysis and that predicted by the formulae developed by Van Slyke, Wu, and McLean. The data in this paper present further experimental evidence on the question of whether serum and transudates constitute a heterogeneous system in appro~dmate thermodynamic equilibrium; and whether the membrane separating them is freely diffusible to inorganic anions and cations as is collodion, or whether it has properties of selective permeability as has the red cell membrane.

The Ultrafiltrability of Potassium and Sodium in Human Serum

“…Distribution ratios of potassium and sodium in serum of these subjects corresponded very closely to predictions of the Gibbs-Donnan equilibrium (16). This ratio in the case of sodium coincides almost exactly with mean values already reported in man and other animals (17)(18)(19)(20)(21)(22)(23). The distribution coefficient of potassium approximated that found in work on dogs (20) and in recent studies of Folk, Zierler, and Lilienthal (23) as well as of Berliner, Kennedy, and Hilton (24).…”

The Origin and Nature of Normal Synovial Fluid 12

“…In other body fluids which have the composition of dialysates the fluid pH has been found to be slightly higher (0.02 to 0.05 unit) than that of the serum (61,87 Application of the Gibbs-Donnan theory of mnembrane equilibrium The significance of this theory as applied to the equilibrium between plasma and body fluids is recognized, even though the inability to determine with any degree of accuracy either the activities of ions in so complex a system, or the presence of other modifying factors, makes it impossible to obtain exact mathematical agreement between calculated and observed values. By this theory the distribution of ions is expressed mathematically by the equation:…”

Intracellular Fluid Loss in Hemorrhage

“…The serum sodium falls distinctly, potassium falls, and chloride remains unchanged. Interstitial fluid contains a lower concentration of sodium than plasma (8,9,10), while intracellular fluid probably contains no sodium. Therefore, the inflow into the plasma of interstitial and intracellular fluid will necessarily reduce plasma sodium.…”