Microcirculation (Exam IV) Flashcards Preview

A&P I (Fall 2022) > Microcirculation (Exam IV) > Flashcards

Flashcards in Microcirculation (Exam IV) Deck (26)
Loading flashcards...
1
Q

The human body has how many capillaries?
How many square meters of surface area is this?

A
  • 10+ billion capillaries
  • 500 - 700 sq meters surface area
2
Q

Precapillary sphincters are extensions of what?

A

Arteriolar smooth muscle

3
Q

Where do breaks in the endothelial lining of CV system occur?

A

Trick question, endothelial lining is continuous everywhere.

4
Q

What are the openings in between endothelial cells called?
What typically cannot move through these openings?

A
  • Intercellular Clefts
  • Proteins
5
Q

What are the three main components that comprise the interstitial fluid gel?

A
  1. Collagen
  2. Proteoglycan filaments
  3. Hyaluronic acid (verify)
6
Q

What are free fluid rivulets?
What can cause these rivulets to become engorged?
What occurs if one of these rivulets attaches the capillary?

A
  • H₂O pockets devoid of gel-qualities.
  • Engorgement occurs from H₂O leaving the capillary more than it should.
  • It forms a “highway” that allows for a massive amount of H₂O loss from the capillary.
7
Q

What is the intracellular volume of RBCs?
What is the blood plasma volume?
What do these two combined make?

A
  • RBCs ICF = 2L
  • Plasma = 3L
  • Total blood volume = 5L
8
Q

Filration is the term for what?

A

Fluid movement out of a capillary.

9
Q

What is PCAP?
What is PISF?
What is πCAP?
What is πISF?

A
  • Hydrostatic pressure of capillary
  • Hydrostatic pressure of interstitial fluid
  • Capillary Oncotic Pressure
  • Interstitial Fluid colloid osmotic pressure
10
Q

What is oncotic pressure?
What other term could be used to name oncotic pressure?

A
  • The pressure of the proteins in the capillaries that tries to pull fluid into the capillaries.
  • Capillary colloid osmotic pressure.
11
Q

Which capillary pressure forces favor filtration?

A
  • PCAP
  • PISF
  • πISF
12
Q

Which capillary forces disfavor filtration?

A

πCAP

13
Q

What is the arterial PCAP?
What is the arterial PISF?
What is the arterial πCAP?
What is the arterial πISF?

A

PCAP = 30mmHg
PISF = -3mmHg
πCAP = 28mmHg
πISF = 8mmHg

14
Q

How would arterial NFP (net filtration pressure) be calculated?

A

NFP = (PCAP + PISF + πISF) - πCAP

15
Q

Which capillary force changes when talking about the capillary forces on the venous end of the capillary beds?
How does it change?
How does this affect NFP?

A
  • PCAP changes from 30 to 10.
  • NFP becomes -7. Filtration becomes disfavored
16
Q

Why does the venous end of capillary beds have less resistance than the arteriolar side?

A
  • Larger surface area
  • More splitting & parallel vessels
17
Q

The average capillary pressure between both arterial & venous sides of the capillary beds should be what?

A

17.3 mmHg

18
Q

What does Inulin measure?

A

Kidney function

19
Q

A higher molecular weight (MW) means what for capillary permeability? Give examples.

A

↑MW = ↓permeability (albumin & hemoglobin).

20
Q

Can lymphatic flow be increased? If so how much?
What is necessary for this?

A
  • Yes by 20x
  • Dependent on skeletal muscles for pumping (SCD’s would help too)
21
Q

Where does the lymphatic system drain into?

A

Subclavian Vein

22
Q

How much fluid can be filtered by the lymphatic system?

A

120 ml/hr

23
Q

What does the lymphatic system collect in addition to interstitial fluid?

A
  • Bad proteins & ISF colloids
24
Q

What protein is the primary contributor to oncotic pressure?
Secondary?
Tertiary?

A
  1. Albumin
  2. Globulins (antibodies, immune system proteins, etc)
  3. Fibrinogen
25
Q

What is the Donnan effect?
What is the result of this effect?

A
  • Cations associate with negatively charged proteins which then prevent ion movement across the endothelium.
  • Result: increase in πCAP (example in lecture was 19 to 28 mmHg)
26
Q

Why might edema be seen with isolated liver failure?

A
  • Decrease in πCAP due to liver not making as many clotting factor proteins that circulate in the blood.