115 Cardiac Output and Venous Return

Question 1

Relationship between Frank-Starling Curve and Cardiac Function Curve

Answer 1

Question 2

Vascular Function Curve

Answer 2

Question 3

Combined Cardiac Function Curve and Vascular Function Curve

Answer 3

Two simultaneous physiologic laws must be satisfied (system of 2 simultaneous equations)
1. Cardiac Function Curve (Frank-Starling Relationship): as RAP increases (a proxy for LVEDP), Cardiac Output Increases
2. Vascular Function Curve: as Cardiac Output increases, RAP falls (negative slope, reversed axes)
For both relationships to be true in a closed steady-state system, there is precisely ONE operating point: the intersection

Question 4

VF / CO Curves: Changes in Contractility

Answer 4

Question 5

VF / CO Curves: Changes in Plasma Volume

Answer 5

Question 6

Unstressed Volume / Stressed Volume in Veins

Answer 6

Question 7

VF / CO Curves: Increased Venous Tone (Venoconstriction)

Answer 7

Question 8

VF / CO Curves: Increase in Systemic Vascular Resistance

Answer 8