Chapter 4: Hyperemia and congestion

Question 1

Because of blood circulation, there is a balance. What is in that balance?

Answer 1

Delivery of oxygen and nutrients, and removal of wastes. Also there is a little net movement of water and electrolytes

Question 2

The balance is often disturbed by pathologic conditions. What are some examples? (just for illustration)

Answer 2

An altered endothelial function, increase vascular hydrostatic pressure, or decrease plasma protein content, all of which promote edema—the accumulation of fluid in tissues resulting from a net movement of water into extravascular spaces.

Question 3

True/false: edema (dutch: oedeem) usually has minimal effects

Answer 3

Not true! It can have minimal or profound effects. (e.g. in the lower extremities, it may only make one’s shoes feel snugger after a long sedentary day; in the lungs, however, edema fluid can fill alveoli, causing life-threatening hypoxia)

Question 4

How is the process of blood clotting that prevents excessive bleeding after blood-vessel damage called?

Answer 4

Hemostasis

Question 5

Inadequate hemostasis may result in …

Answer 5

hemorrhage (which can compromise regional tissue perfusion and, if massive and rapid, may lead to hypotension, shock, and death)

Question 6

What is inappropriate clotting called?

Answer 6

Thrombosis

Question 7

What is migration of clots called?

Answer 7

Embolism

Question 8

Thrombosis and embolism can cause obstruction. How is this called?

Answer 8

Infarction (ischemic cell death)

Question 9

Thromboembolism lies at the heart of three major causes of morbidity and death in developed countries. What are these three?

Answer 9

Myocardial infarction, pulmonary embolism (PE), and cerebrovascular accident (stroke).

Question 10

What do hyperemia and congestion have in common?

Answer 10

An increase in blood volume within a tissue

Question 11

What is hyperemia?

Answer 11

Hyperemia is an active process resulting from arteriolar dilation and increased blood inflow, as occurs at sites of inflammation or in exercising skeletal muscle

Question 12

What colour does hyperemia appear? And why?

Answer 12

Red(der than normal), because of engorgement with oxygenated blood

Question 13

What is congestion?

Answer 13

Congestion is a passive process resulting from impaired outflow of venous blood from a tissue

Question 14

How can congestion occur?

Answer 14

Systemically, as in cardiac failure, or locally as a consequence of an isolated venous obstruction

Question 15

What colour does congestion appear? And why?

Answer 15

Abnormal blue-red color (cyanosis) that stems from the accumulation of deoxygenated hemoglobin in the affected area

Question 16

What are the effects of longstanding chronic congestion?

Answer 16

Inadequate tissue perfusion and persistent hypoxia may lead to parenchymal cell death and secondary tissue fibrosis, and the elevated intravascular pressures may cause edema or sometimes rupture capillaries, producing focal hemorrhages.

Question 17

What is edema?

Answer 17

Edema is an accumulation of interstitial fluid within tissues

Question 18

Fluid movement between vascular and interstitial spaces is governed by mainly two opposing forces. Which two?

Answer 18

The vascular hydrostatic pressure and the colloid osmotic pressure produced by plasma proteins

Question 19

Normally, the outflow of fluid produced by…

Answer 19

hydrostatic pressure at the arteriolar end of the microcirculation is nearly balanced by inflow at the venular end owing to slightly elevated osmotic pres- sure

Question 20

Either increased hydrostatic pressure or diminished colloid osmotic pressure causes increased movement of water into the extracellular/intracellular space

Answer 20

Extracellular space

Question 21

How is excess edema fluid removed?

Answer 21

By lymphatic drainage

Question 22

Fill in: The edema fluid that accumulates in the setting of increased hydrostatic pressure or reduced intravascular colloid osmosis typically is a protein-POOR/RICH transudate;

Answer 22

Poor

Question 23

Fill in: Increased vascular permeability, inflammatory edema fluid is a protein-POOR/RICH exudate with a high specific gravity.

Answer 23

Rich

Question 24

Increases in hydrostatic pressure are mainly caused by disorders that impair venous return. What are some examples/causes of local increases in intravascular pressure?

Answer 24

Deep venous thrombosis in the lower extremity that can cause edema restricted to the distal portion of the affected leg

Question 25

Pleeaasse look at figure 4.3

Answer 25

okay

Question 26

Does a high or low capillary hydrostatic pressure cause edema?

Answer 26

High

Question 27

Does a high or low renal blood flow cause edema? (and explain steps please)

Answer 27

Low (by activation of the renin-angiotensin-aldosterone system -> retention of Na+ and H2O -> higher blood volume)

Question 28

What happens to the capillary hydrostatic pressure and renal blood flow when there is heart failure?

Answer 28

High capillary pressure, lower renal blood flow, eventually resulting in edema

Question 29

How can, in the case of heart failure, the fluid retention (edema) be treated?

Answer 29

With salt restriction, diuretics, and aldosterone antagonists

Question 30

Fill in: Reduction of plasma albumin concentrations leads to decreased/increased colloid osmotic pressure of the blood and gain/loss of fluid from the circulation

Answer 30

Decreased and loss

Question 31

Under normal circumstances, albumin accounts for almost … of the total plasma protein

Answer 31

half

Question 32

What is the most important cause of albumin loss from the blood

Answer 32

Nephrotic syndrome (where the glomerular capillaries become leaky, leading to the loss of albumin (and other plasma proteins) in the urine and the development of generalized edema)

Question 33

Due to what condition is there a reduced albumin synthesis?

Answer 33

Severe liver disease such as cirrhosis and protein malnutrition

Question 34

Explain, stepwise, how low albumin levels leads to edema

Answer 34

low album levels -> reduced intravascular volume -> renal hypoperfusion -> secondary hyperaldosteronism

Question 35

Edema may result from … obstruction that compromises resorption of fluid from interstitial spaces.

Answer 35

lymphatic

Question 36

What is lympatic edema also called?

Answer 36

Lymphedema

Question 37

Name some conditions where lymphedema might occur (3 examples are given here)

Answer 37

• parasitic infection filariasis

- breast cancer (and during surgery, axillary lymph node resection)

Question 38

Fill in: Excessive retention of salt (and its obligate associated water) can lead to edema by reducing/increasing hydrostatic pressure and reducing/increasing plasma osmotic pressure.

Answer 38

increasing (because of expansion of the intravascular volume) and reducing respectively

Question 39

Where is subcutaneous edema usually found?

Answer 39

Furthest below the heart (because hydrostatic pressure is highest)

Question 40

Edema is, standing, often found in the legs, and lying down in the sacrum (heiligbeen). How is this phenomenon called?

Answer 40

Dependent edema (cause it follows the highest hydrostatic pressure)

Question 41

Why is subcutaneous edema important to recognize?

Answer 41

Because it signals potential underlying cardiac or renal disease; however, when significant, it also can impair wound healing and the clearance of infections.

Question 42

Finger pressure over edematous subcutaneous tissue displaces the interstitial fluid, leaving a finger-shaped depression. How is this appearance called?

Answer 42

Pitting edema

Question 43

Edema resulting from renal dysfunction or nephrotic syndrome often manifests first in loose connective tissues. Name an example.

Answer 43

The eyelids, causing periorbital edema

Question 44

What happens when there is pulmonary edema?

Answer 44

The lungs often are two to three times their normal weight, and sectioning shows frothy, sometimes blood-tinged fluid consisting of a mixture of air, edema fluid, and extravasated red cells.

Question 45

True/false: brain edema is often localized

Answer 45

False! Brain edema can be localized (e.g., because of abscess or tumor) or generalized, depending on the nature and extent of the pathologic process or injury. With generalized edema, the sulci are narrowed as the gyri swell and become flattened against the skull.

Question 46

Pulmonary edema is a common clinical problem. With what kind of disorder is it most frequently seen?

Answer 46

With left ventricular failure (but also may occur in renal failure, acute respiratory distress syndrome, and inflammatory and infectious disorders of the lung)

Question 47

How is pulmonary edema fatal?

Answer 47

It can cause death by interfering with normal ventilatory function; besides impeding oxygen diffusion, alveolar edema fluid also creates a favorable environment for infections

Question 48

True/false: brain edema can be fatal, depending on its location

Answer 48

False! Brain edema is life threatening; if the swelling is severe, the brain can herniate (extrude) through the foramen magnum. With increased intracranial pressure, the brain stem vascular supply can be compressed, leading to death due to injury to the medullary centers controlling respiration and other vital functions