Circulatory adjustments to anemic hypoxia.

Abstract

Oxygen transfer in the circulation can be reduced in a number of ways, as Barcroft described many years ago (Barcroft, 1920). Following his nomenclature, we will describe some of the circulatory responses to hypoxic hypoxia (Barcroft’s anoxic type), which is a condition of lowered arterial PO2, and to anemic hypoxia, which is a condition of lowered arterial O2 concentration. Most attention will be directed toward the latter type because, in the case of experimental hemodilution particularly, there are some fascinating differences from hypoxic hypoxia that occur for reasons that are not immediately obvious.