The Energy Distribution in the Pulmonary Circulation, I: Theory

Abstract
The principles of conservation of energy and of mass have been applied systematically to the pulmonary circulation. This approach has led to the concept of an "effective resistance", based on the dissipation of energy rather than the drop in pressure. This concept includes the effect of kinetic energy and allows an assessment of its importance. The equations and concepts applied in this paper to the pulmonary circulation apply equally well to the systemic circulation and to the flow of fluids in biological systems in general.