A-V O2 difference can increase considerably for some tissues during periods of maximal O2 utilization (Figure 3.01). This is true, for example, for skeletal muscle. The heart however has only a very limited ability to increase A-V 02 diff., mainly because it is already so high; to increase it further would mean than areas of the myocardium would become hypoxic. Thus, to increase oxygen delivery the heart must increase blood flow.
BACK TO INDEX