C- Hemodynamics & Vasculature Flashcards Preview

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Flashcards in C- Hemodynamics & Vasculature Deck (28):
1

________ is Highest in aorta.

Pressure

Pressure decreases through system, especially in resistance vessels (sm arteries & arterioles)

2

Pressure is_______ in capillaries and venous system

low

3

Total blood volume ~ 5 L
Largest volume in _______(“capacitance vessels”)

veins

4

Q = DP/R

this represents?

Q = DP/R

Pressure differences (ΔP) drive blood flow (Q). Vascular resistance (R) opposes blood flow.

5

volume per unit time (ml/min)
CONSTANT through system (since closed loop)
CARDIAC OUTPUT (CO) = Total flow in the cardiovascular system

Flow (Q)

6

distance per unit time (cm/sec)
v=Q/A (flow/cross sectional area)
Velocity highest in aorta (lowest total cross-sectional area), lowest in capillaries (greatest cross-sectional area).

Velocity (v)

7

CO = (Pa-Pv)/TPR

Cardiac Output

Pa = mean arterial blood pressure
Pv = venous blood pressure
TPR = total peripheral resistance

Variation of flow equation: Q=DP/R

8

_______ is the volume of blood pumped per minute by the heart (~5 L/min at rest)

Cardiac Output (CO)
CO = (Pa-Pv)/TPR

9

___________ corresponds to the total flow in cardiovascular system

Cardiac Output
CO = (Pa-Pv)/TPR

10

Flow is proportional to 4th power of radius. Thus ___________ is the biggest determinant of flow.

radius of vessel

11

Flow is proportional to ____________. Thus radius of vessel is the biggest determinant of flow.

4th power of radius

12

resistance of a parallel network is ________ than the resistance of any single vessel

lower

*Changing the resistance of a single vessel has little effect on the system

13

Total resistance of a series of vessels is _________ than the resistance of any individual vessel

higher

*Resistances in series are additive

14

(flow)
Most efficient
Velocity fastest in center, zero at edge
Flow equation assumes this flow. Not true in CV system

Laminar flow

15

(flow)

Irregular, with eddies and vortices

Less efficient – requires more pressure to achieve same velocity

Promoted by large diameter, high velocity, low viscosity, changes in diameter, and irregularities on walls

Turbulent flow

*Turbulent flow produces shearing forces that can damage vascular endothelium

16

Heartbeat produces _____ flow in aorta, but _____ flow requires more work. dampened in arterial system.

pulsatile

17

FLOW IS __________IN CAPILLARIES

CONTINUOUS

18

Systolic pressure =

peak aortic pressure

19

Diastolic pressure =

minimum aortic pressure

20

Blood pressure is expressed as

systolic/diastolic = ex 120/80 mmHg

21

Vessels lose compliance with age =

arteriosclerosis

Compliance represents the elastic properties of vessels (or chambers)

22

arteriosclerosis results in

Older people have higher systolic pressure and higher pulse pressure than younger people

23

Tension in wall increases as pressure and radius increase.

Walls of larger vessels subject to greater tension.

________ increases stress on walls of vessels and chambers.

Hypertension

24

Law of LaPlace:

Relationship between wall tension & transmural pressure

25

Cardiovascular Transport Two processes

Bulk transport
Transcapillary transport

26

refers to movement of a substance through the cardiovascular system from point A to point B.

Bulk transport

27

describes the movement of a substance between capillaries and tissue

Transcapillary transport

28

Diffusion follows _________ concentration gradients

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