Abstract: Techniques for predicting the respective concentrations and distributions of diffusible materials in solutions on opposing sides of a semi permeable membrane are provided. Unique compositions for hemodialysis using the mathematical relationships involved are provided. Also processes are provided for controlling the rate of change in concentration of a diffusible material in and fluid into another fluid on an opposing side of semi-permeable membrane are provided. Apparatus for practicing such processes are described.

Abstract: Methods are provided for preparing just before administration unit doses of therapeutic solutions which contain redox active unstable and/or diffusable metabolites such as ketoacid, a sulfhydryl-containing amino acid, or carbon dioxide. The method involves preparing and storing an aqueous solution of stable components which may or may not contain carbon dioxide. A dry powder comprised of unstable components is also prepared and stored separately. These separate component compositions are packaged in, for example, individual chambers of a common sealed container which is so constructed as to permit the opening, by externally applied manual means or the like, of a passageway between such chambers at the time when usage is contemplated. Thus, a fresh solution in desired full dosage form is preparable just before administration. Improved container structures for practice of this method are also provided.

Abstract: Techniques for predicting the respective concentrations and distributions of diffusible materials in solutions on opposing sides of a semi permeable membrane are provided. Unique compositions for hemodialysis using the mathematical relationships involved are provided. Also processes are provided for controlling the rate of change in concentration of a diffusible material in and fluid into another fluid on an opposing side of semi-permeable membrane are provided. Apparatus for practicing such processes are described.

Abstract: Processes and compositions are provided for in vitro use in tissue culture media (preferred), perfusion media, and incubation media. Thus, balanced salt solutions are provided wherein the milliequivalent ratio of sodium cations to chloride anions is normalized and wherein optionally at least one near-equilibrium couple is incorporated (bicarbonate.sup.- /carbon dioxide, L-lactate.sup.- /pyruvate.sup.-, and d-betahydroxybutyrate.sup.- /acetoacetate.sup.-. Regulation of intracellular and extracellular pH, and normalization of intracellular redox state and phosphorylation state is achievable.

Abstract: Electrolyte solutions are provided which are useful in electrolyte and fluid therapy, parenteral nutrition, and dialysis. The Na:Cl ratio is normalized, plasma and cellular pH are normalized, and cellular cofactor ratios are normalized, in a manner which decreases toxicity over prior art solutions. The solutions employ at least one of the following near-equilibrium couples: (a) bicarbonate/CO.sub.2 ; (b) 1-lactate/pyruvate; and (c) d-betahydroxybutyrate/acetoacetate.

Abstract: The use of non diffusible organic polyionic materials in aqueous electrolyte solutions is taught wherein the electrolyte types and concentrations are suitable for use in treating living animal cells (including mammals and man). In these solutions, the Na:Cl ratio is normalizable without the use of unphysiological or demonstrably pathological amounts or ratios of small diffusible anions. Effective plasma expanders and plasma substitutes are provided. Near equilibrium couples may be incorporated if desired.