Hemorrhage and Exercise

Question 1

Systemic Circulation

Answer 1

each segment of the vascular system has a specific purpose

Question 2

Plotting arterial pressure (Pa or MAP) versus flow (CO) –> slope

Answer 2

= resistance (TPR)

Question 3

Ca

Answer 3

= deltaVolume/deltaPressure

Question 4

Voa

Answer 4

= unstressed arterial volume (amount of blood in vessels before pressure starts to increase)

Question 5

Plotting arterial pressure (Pa or MAP) versus Arterial volume (Va) –> slope

Answer 5

= 1/Ca

Question 6

Vov

Answer 6

= unstressed venous volume (amount of blood in vessels before pressure starts to increase)

Question 7

Va =

Answer 7

Voa + CaPa

Question 8

Vv =

Answer 8

Vov + CvPv

Question 9

Plotting venous pressure (Pv) versus Venous volume (Vv) –> slope

Answer 9

= 1/Cv

Question 10

Assume constant blood volume, Vt

Answer 10

= Va + Vv

Question 11

Venous return curve

Answer 11

The slopes (and unstressed volumes) change due to the ANS (alpha1-receptors on blood vessels) TPR, Cv (and to lesser extent Ca), and Vtotal are all important

Question 12

Where is equilibrium?

Answer 12

CO = Venous Return, in quadrant 1, the intersection of the heart (Starling Curve) and vessels (Venous Return Curve)

Question 13

What happens during hemorrhage

Answer 13

loos of volume, venous curve shifts downward with no change in slope (decrease in MSFP), baroreceptors respond with increased contractility (increase in contractility and decrease in Cv venous constriction)

Question 14

During hemorrhage

Answer 14

Decrease in capillary pressure

Question 15

Stroke volume increases almost to maximal levels immediately upon exercising

Answer 15

EDV increase due to increase venous return, ESV decrease due to increased contractility, SV increase due to increase EDV and decrease ESV, Ejection fraction increase due to increase in SV/EDV

Question 16

HR increases

Answer 16

linearly with work

Question 17

SV increases

Answer 17

small amount early on

Question 18

CO increases

Answer 18

HR * SV (linear)

Question 19

MAP increases

Answer 19

CO increases * decreased TPR

Question 20

TPR decreases

Answer 20

due to vasodilatio

Question 21

Aerobic training

Answer 21

increases SV, heart gets stronger

Question 22

What happens during exercise

Answer 22

decreases in systemic circulation (decreased TPR, Cv) and increases i the heart (increased HR and contractility)

Question 23

Hemorrhage short term

Answer 23

baroreflex activates ANS

Question 24

Hemorrhage long term

Answer 24

fluid shifts into capillaries, replace volume (day), make new RBC (weeks)

Question 25

Exercise short term

Answer 25

Increase HR, contractility, and venous return (decreased Cv), increased baroreceptor set point

Question 26

Exercise long term

Answer 26

Increase stroke volume, decreased HR –> stronger, healthier heart