cardiovascular system design Flashcards Preview

physiology IV > cardiovascular system design > Flashcards

Flashcards in cardiovascular system design Deck (30):
1

what are the 5 main functions of the cardiovascular system?

1. contractions of individual cardiac cells must occur at regular intervals and be synchronized
2. valves must fully open
3. valves must not leak
4. muscle contractions must be forceful
5. ventricles must fill adequately durning diastole

2

about how many liters are there in the interstitial compartment (internal environment)?

12 L

3

about how many liters are there in the intracellular compartment?

30 L

4

about how many liters are there in the circulating plasma compartment?

3 L

5

out of the kidney, skeletal muscle, liver/GI tract, brain and heart which organ has the highest VO2 (O2 consumption as a percentage)

skeletal muscle (about 27%)

6

out of the kidney, skeletal muscle, liver/GI tract, brain, skin and heart which organ has the lowest VO2 (O2 consumption as a percentage)

kidney (about 7%)

7

at any point in time, what percentage of blood is systemic circulation?

~84%

remainder in hear (~7%) and pulmonary vessels (~9%)

8

where does the right ventricle pump blood into?

pulmonary circulation

9

how does re-oxygenated blood return to the L. atrium

pulmonary veins

10

what two valves regulate the entry of blood into systemic circulation?

mitral and aortic valves

11

what two valves regulate the entry of blood into pulmonary circulation?

tricuspid and pulmonary valves

12

define cardiac output

quantity of blood per unit time pumped into the aorta by the heart
SV x HR

13

what is the typical cardiac output for a resting individual?

5 L/min

14

what are the 3 major determinants of stroke volume?

-ventricular preload
-ventricular afterload
-myocardial contractility

15

list 3 factors that can decrease CO

-siting or standing from lying position
-rapid arrhythmia
-heart disease

16

list 5 factors that can increase CO

-anxiety and excitement
-eating
-exercise
-high environmental temp
-pregnancy
-epi

17

what does starling's law state

stroke volume increases as end diastole volume increases (other things being constant)

18

define mean arterial pressure

the average pressure over the entire cardiac cycle. It is estimated from diastolic pressure and pulse pressure
MAP= CO x TPR

19

define pulse pressure

it is the difference between the systolic and diastolic pressure

20

define systolic pressure

peak pressure reached during blood ejection from the heart

21

define diastolic pressure

lowest pressure point during which the heart is filling with blood

22

what is the dichrotic notch

it is the small dip caused by the backfilling of the aortic valve as it closes

23

where is the circulatory system is blood pressure the lowest? the highest?

the lowest: pulmonary veins
highest: large arteries

24

is taking BP via the ausculatory method considered direct or indirect?

indirect

25

how do you measure pulmonary venous and left arterial pressures?

need to use pulmonary capillary wedge pressure

26

what is the average pulse pressure in a resting adult?

40 mmHG

27

give two equations to calculate pulse pressure

PP= SD-DP
PP= SV/compliance

28

in the short term, how is MAP controlled? how is this accomplished?

by altering peripheral resistance and cardiac output
this is accomplished neurally and hormonally

29

how is long term control of MAP achieved?

primarily by altering blood volume via the kidneys

30

what is the units for human blood pressure?

mercury (because we calculate BP in regards the environmental pressure)