REGULATION OF TISSUE OXYGENATION

In summary, a number of factors have been shown to influence O2 delivery to the tissues. In addition to regulation of oxygen binding by hemoglobin and myoglobin, regulation of microvascular perfusion and exchange area will also impact upon O2 delivery. These latter influences are summarized in Figure 6. Although O2 delivery is frequently evaluated at the macrovascular level, this figure illustrates the fact that the actual focus for regulation of that delivery is at the level of the microcirculation. Thus, intra- and interorgan heterogeneities in microvascular structure, function, and hemodynamics will likely have a substantial impact upon O2 uptake and delivery relationships.