Lymphatics Quiz

Question 1

What is capillary filtration?

Answer 1

The sum of the hydrostatic and osmotic forces favors the net movement of water from the capillary to the interstitial space

Movement of fluid out of the capillary

Question 2

What is capillary reabsorption?

Answer 2

The sum of the hydrostatic and osmotic forces favors the net movement of water from the interstitial space to the capillary

Movement of fluid back into the capillary

Question 3

What are the Starling Forces with regards to capillary filtration/reabsorption?

Answer 3

Capillary Pressure, Interstitial Fluid Pressure, Plasma Colloid Osmotic Pressure, Interstitial Fluid Colloid Osmotic Pressure

Question 4

What is osmosis?

Answer 4

Water moves from a region of high concentration to one that has a lower concentration of water

Question 5

If Net Driving Forces are positive, does it favor capillary filtration or reabsorption?

Answer 5

Filtration NDF>0 filtration

NDF<0 Reabsorption

Question 6

Are hydrostatic pressures within the capillary equal at the arteriolar end and the venous end?

Answer 6

No, equal at venous end

Question 7

Under normal circumstances, what Net Driving Force favors fluid movement INTO the capillary?

Answer 7

Reabsorption

plasma oncotic pressure

Question 8

What would the Net Driving Forces be in a patient with congestive heart failure? Would they favor filtration or reabsorption?

Answer 8

Increased Capillary Hydrostatic Pressure

Filtration

Question 9

What is the function of the lymphatic system?

Answer 9

The lymphatic system helps to maintain fluid balance, defend the body against disease, and absorb liquids from the intestine and transport them to the blood.

The lymphatic System collects and returns fluid that leaks from blood vessels. It absorbs fats and vitamins. Lastly, it defends against invading microorganisms and disease

Question 10

How is plasma filtrate returned to the circulation by the lymphatic system?

Answer 10

Tissue pressure
Intermittent skeletal muscle activity
Lymphatic vessel contraction
System of one-way valves

Question 11

What is the thoracic duct? Where is it found and what does it connect to?

Answer 11

the largest lymphatic vessel in the body

Left SC Vein

Question 12

What things may cause edema?

Answer 12

Lymphatic obstruction

Change in capillary permeability

Reduction in plasma protein

Increased capillary hydrostatic pressure

Question 13

Name 3 endogenously found vaso-constricting substances.

Answer 13

Catecholamines
-Epinephrine
-Norepinephrine
-Dopamine
Endothelin
Serotonin
Angiotensin II
Vasopressin

Question 14

Name 3 endogenously found vaso-dilating substances.

Answer 14

Histamine
Adenosine
Nitric Oxide (NO)
Carbon Dioxide
Potassium
Hydrogen Ion
Prostaglandins
Acetylcholine
Bradykinin

Question 15

What is the Metabolic Mechanism? What substance is responsible for this mechanism?

Answer 15

Any intervention that results in an inadequate oxygen (nutrient) supply for the metabolic requirements of the tissues results in the formation of vasodilator substances which increase blood flow to the tissues

One of the most fundamental principles of circulatory function is the ability of each tissue to control its own local blood flow in proportion to its metabolic needs

Question 16

What is the Myogenic Mechanism?

Answer 16

When the lumen of a blood vessel is suddenly expanded, the smooth muscle responds by contracting in order to restore the vessel diameter and resistance, The converse is also true.

Question 17

What is Reactive Hyperemia? Give a common clinical example of Reactive Hyperemia.

Answer 17

the transient increase in organ blood flow that occurs following a brief period of ischaemia. Following ischaemia there will be a shortage of oxygen and a build-up of metabolic waste.
Example: Tourniquet, Raynauds

Question 18

What is Autoregulation? What mechanism of blood flow regulation is thought to be involved?

Answer 18

Intrinsic ability of an organ to maintain a constant blood flow despite changes in perfusion pressure

Possible explanations for Autoregulation:
Myogenic Mechanism

Question 19

Name 3 endothelial factors that help regulate blood flow?

Answer 19

Vasoactive substances released from endothelium:
Nitric Oxide (NO)
Endothelium-derived relaxing factor 
Prostacyclin 
Endothelin
Endothelial-derived hyperpolarizing factor (EDHF)

Question 20

What is nitric oxide? How might it be helpful during one-lung ventilation?

Answer 20

It is a powerful vasodilator with a short half-life of a few seconds in the blood

used in critical care to promote capillary and pulmonary dilation to treat primary pulmonary hypertension

improves V/Q mismatch

Question 21

Is Endothelin a vaso-dilator or -constrictor?

Answer 21

Potent vasoconstrictor

Question 22

Why are blood vessels prone to vaso-constriction, vaso-spasm and thrombosis when the endothelium is damaged?

Answer 22

Decreased nitric oxide and prostacyclin production

Increased endothelin production