Lecture 15: TBL Ventricular Fxn

Question 1

Identify the best indexes of preload, afterload, and inotropic state on the PV loop

Answer 1

Preload = LVEDP

afterload = LVESP

IS = slope of line from origin to afterload

Question 2

Describe major contributors to preload

Answer 2

Volume of blood returning to heart from veins = venous return

3 determinants of venous return = venous capacitance, blood volume, SKM contraction

Question 3

Give examples of interventions or physiological changes that affect preload

Answer 3

Physiological changes: inc. SKM contraction or blood volume, dec. venous capacitance

Intervention: blood transfusion will inc. PL

Question 4

Describe main contributor to afterload

Answer 4

BP

Determinants = CO and SVR

Question 5

Describe physiological changes that affect contributors of afterload

Answer 5

Arteriole constriction will increase SVR and then increase AL

Question 6

Describe major contributor of inotropic state

Answer 6

Intracellular calcium