CHAPTER 32 



Venous return 



ARTHUR C. GUYTON 



Department of Physiology and Biophysics, University of Mississippi 

 School of Medicine, Jackson, Mississippi 



CHAPTER CONTENTS 



Introduction 



Principles of Circuit Analysis as They Apply to Venous 



Return 

 The problem 

 Solution to the problem 

 The Classical Analysis of Venous Return — Vis a Tergo 



and Vis a Fronte 

 History of More Complete Circulatory Analyses 

 Simplified Graphical Analysis of Venous Return, Cardiac 



Output, and Right Atrial Pressure 

 Cardiac Output Curves 



Effectiveness of the heart as a pump 



Alteration of the load against which the heart must 



pump 

 Alterations in pressure on the outside of the heart 

 Summary of factors that affect the cardiac output 



curves 

 Venous Return Curves 



Venous return curves as complements to cardiac output 



curves 

 Method for recording venous return curves 

 Effect of right atrial pressure on venous return — the 



normal venous return curve 

 Effect of peripheral resistance on venous return 

 Effect of mean systemic pressure on venous return 

 Summary of factors that affect the venous return 



curves 

 Equating the Venous Return and Cardiac Output Curves 

 Effect of sympathetic stimulation on venous return, 



cardiac output, and right atrial pressure 

 Effect of muscular exercise on venous return, cardiac 



output, and right atrial pressure 

 Effect of rapid transfusion on venous return, cardiac 



output, and right atrial pressure 

 Effect of shock on venous return, cardiac output, and 



right atrial pressure 

 Effect of opening the chest on venous return, cardiac 



output, and right atrial pressure 

 Effect of myocardial damage on venous return, cardiac 



output, and right atrial pressure 

 Analysis of decompensation and compensation in con- 

 gestive heart failure 



Analysis of effects resulting from changes in vascular 



resistance 

 A More Complex Graphical Analysis of Venous Return, 



Ventricular Outputs, and Atrial Pressures 

 Balance of the two ventricular outputs with each other 

 Effect of acute left heart failure on cardiac output, 



venous return, left and right atrial pressures, mean 



systemic pressure, and mean pulmonary pressure 

 Effect of acute right heart failure 

 Effect of blood volume change 

 Summary of the complex analysis 

 Specific Factors that Affect Venous Return 



Effect of the venous pump on venous return 



Effect of venous collapse on venous return 



Effect of central pulsation on venous return 



Effect of local tissue activity on venous return — effect 



of oxygen usage by the tissues 

 Venous Pressures 



Effect of resistance to flow in the veins 



Effect of venous flow on peripheral venous pressures 



Effect of hydrostatic pressure on peripheral venous 



pressures 

 Summary 



INTRODUCTION 



the term "venous return" means very simply the 

 flow of blood from the veins into the heart, and this, 

 obviously, can be divided into ''systemic venous re- 

 turn" and "pulmonary venous return." The function 

 of the veins and the importance of venous return have 

 been covered from different points of view in several 

 important monographs (31, 70) and reviews (72, 

 82-85, 1 33> 137)- Also, the basic characteristics of the 

 veins as blood vessels are reviewed by Alexander in 

 Chapter 31 . Therefore, the purpose of this chapter will 

 be to discuss especially the regulation of venous return 

 and secondarily the associated factor venous pressure. 



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