Circulation

Question 1

Velocity of Blood

Answer 1

v- F/A Volume of blood flow/Vascular cross-sectional area

Question 2

Aortic and Pulmonary pressures are….

Answer 2

pulsatile

Question 3

Blood through lung each minute = ?

Answer 3

Systematic Blood Flow Each minute

Question 4

Normal arterial P = ?

Answer 4

100 mmHg

Question 5

Cardiac output = ?

Answer 5

sum of all local tissue flows

5000 ml/min

Question 6

Arterial flow regulation is separate from…

Answer 6

local blood flow control AND cardiac output control

Question 7

Arterial P fall below 100 mmHg =?

Answer 7

(Baroreceptors signal to) Increase Sympathetic tone = increase force of heart rate pumping blood AND cause contraction of venous reservoirs to get blood back to heart AND generate contriction of most arterioles throughout the body so more blood accumulates in the arteries (and decrease parasympathetic effects)

THEN kidneys produce pressure-controlling hormones and regulate the blood volume (for the next few days)

Question 8

Blood flow is determined by…

Answer 8

1) Pressure gradient between 2 ends of vessel
2) Vascular resistance (friction)

SO Q = ∆P/R
Flow = (Arterial P - Venous P) / Resistance

AND viscosity and length of vessel

Question 9

Laminar Flow

Answer 9

Silent = streamlines

Velocity in the center is faster than the outsides

Question 10

Turbulent Flow

Answer 10

eddy current = whirl pools

Question 11

Measuring BP

Answer 11

1. Constrict the blood vessel
   
   2. Slowly decrease constriction
   3. Greater than 120 mmHg = no blood flow
   4. Between 80 and 120 mmHg = systolic blood flow
   5. Under 80 mmHg = laminar blood flow

Question 12

Systemic circulation

Answer 12

Peripheral circulation

body minus lungs and abdominal viscera

84% of blood vol (lungs = 9% and heart = 7%

Question 13

Vessel must be ——–

Answer 13

distensible

Arteries = to accomodate pulsatile output
Veins = act as a reservoir

Question 14

vascular distensibility equation

Answer 14

Vascular Distensability = Increase in Volume / (Increase in P x Original Volume)

Question 15

Arterial P Equation

Answer 15

Arterial Pressure = Cardiac Output x Peripheral Resistance

Question 16

Pulse P

Answer 16

Difference between systolic P (120mmHg) and diastolic P (8o mmHg)

40 mmHg

Question 17

If you decrease in compliance of veins = ?

Answer 17

Blood goes to heart = inc in venous return

Question 18

If you increase in compliance of veins = ?

Answer 18

decrease in venous return

Question 19

R atrial P =?

Answer 19

central venous P

Question 20

R atrial P is balanced by…

Answer 20

1) Ability of the heart to pump blood OUT of R atrium and ventricles to the lungs

0 mmHg

Stronger beaters = negative bc blood is sucked from atrium to ventricles when heart is relaxed

Weaker beaters = 20-30 mmHg bc blood leaks into tissue

2) venous return (dep on blood volume and venous compliance)

OVERALL = ability of blood to leave and return to R atrium

Question 21

Effects of RAP on venous P

Answer 21

1) RAP = 0 mmHg = all veins are collapsed = no resistance
2) RAP > 0 = blood begins to back up into large veins = veins begin to open
3) RAP = 4-6 = veins have ALL opened
4) RAP > 6 = corresponding rise in peripheral P in order for blood to flow back to heart

Question 22

Aortic Regurgitation

Answer 22

Blood leaks from SA valve during ventricular relaxation

More blood pumped out of aorta = quicker drop in aortic P bc quicker flow of blood through the body = more volume per minute brought back to the heart = inc in PULSE P

Question 23

Inc in stroke volume = —– in pulse P

Answer 23

Inc

Question 24

Inc in blood flow to tissue = —— in venous return = —– in CO

Answer 24

Increase for both