An analysis of factors affecting tissue oxygen tension

Abstract A mathematical analysis of the factors affecting the distribution of oxygen in living tissue is the subject of this paper. The Erlang -Krogh equation discussed in § 1 is derived from a highly simplified model, comprising a long, straight capillary surrounded by a cylinder of respiring tissue. Succeeding sections describe the effects upon the distribution of oxygen as predicted by this model of the following factors: (a) Hexagonal rather than cylindrical symmetry. (b) Decrease in the rate of consumption of oxygen by the cells in the tissue when the oxygen tension falls below a certain value. (c) Variation of the diffusion constant with position in the tissue. (d) A sudden change in the value of the oxygen tension at the capillary surface. (e) A decrease in oxygen tension along the length of the capillary. (f) Fluid flow in the extracellular fluid.