Systemic oxygen transport and utilization

This short review addresses modern concepts of oxygen transport and utilization. It consists of two sections. The first deals with the underlying concepts and is largely theoretical. It first presents the transport pathway components as a linked in series system. Then, the way in which the components are integrated to set limits to overall O(2) availability to tissue mitochondria is discussed. It therefore presents a framework for interpreting O(2) transport limitations, both in health and disease. The second section deals with experimental outcomes of studies that address the pathway components and the limitations they may impose on O(2) availability using that framework. Most of these studies have involved exercise in healthy subjects, but some have examined the relationship between O(2) supply and utilization in critically ill patients. An application suitable for intact transgenic mouse phenotyping studies is also proposed.