Pathology

Question 1

Definition: edema

Answer 1

Increased interstitial fluid

Question 2

Terms regarding other sites of increased fluid:

Answer 2

1. Hydrothorax
2. Hydropericardium
3. Hydroperitoneum

Question 3

Causes of edema

Answer 3

1. Increased hydrostatic pressure
2. Reduced plasma osmotic pressure
3. Lymphatic obstruction
4. Sodium retention
5. Inflammation

Question 4

Increased hydrostatic pressure causes edema through ___

Answer 4

Impaired venous return

Arteriolar dilation

Question 5

What is hyperemia?

What kind of process? (Active or passive)

Answer 5

Arteriolar dilation leads to increased blood flow and engorgement of vessels with oxygenated blood

Active process

Question 6

What is congestion?

What kind of process? (Active or passive)

Answer 6

Reduced outflow of blood causes increased volumes of deoxygenated blood, increased pressure, and stasis

Passive process

Question 7

Classic sites of congestion

Answer 7

Lungs
Liver
Extremeties

Question 8

Definition: hemorrhage

Hemorrhages in skin, mucous membranes, or serosal surfaces have specific names:

Answer 8

A release of blood into extravascular space

Petechiae 1-2 mm
Pupura >3 mm
Ecchymosis >1-2 cm

Question 9

Clinical significance of hemorrhage depends on ___ and ___

Answer 9

Volume and rate of blood loss

Question 10

Virchow’s Triad

Answer 10

1. Endothelial injury
2. Stasis or turbulent blood flow
3. Hypercoagulability

Thrombosis: excessive clotting

Question 11

Thrombi on heart valves are ___

Answer 11

Vegetations

Question 12

Thrombi are usually attached __

and tend to propagate towards __

Answer 12

Attached at their site of origin

Propagate towards the heart

Question 13

What happens to thrombi?

Answer 13

Propagate
Embolism
Dissolve
Organize/recanalize
Microbial seeding >> mycotic aneurysm (rare)

Question 14

Definition: emboli

Answer 14

Detached intravascular solid, semisolid, or gaseous mass carried by the blood to a site distant from the point of origin

Question 15

Pulmonary emboli usually originate from __

Answer 15

DVT of leg above the knee

Question 16

Fat emboli usually originate __

Answer 16

From marrow of broken long bones

Question 17

Fat emboli are sometimes accompanied by __

Answer 17

Rash

Question 18

Air emboli causes?

Answer 18

Decompression sickness from gas bubbling in tissues (esp. nitrogen)

Introduction of >100 cc of air into a vessel during a procedure

Question 19

Amniotic fluid emboli causes

Answer 19

Rupture of membranes and concurrent year of uterine vessels

High maternal mortality rate

Pathognomic: items present in amnion (fetal squames, lanugo hairs, etc) are present in embolus

Question 20

Definition: infarct

Answer 20

Coagulation necrosis corresponding to a particular vascular distribution caused by either arterial or venous occlusion

99+% are thromboembolic

Question 21

Types of infarcts:

Answer 21

Red (hemorrhagic)

• venous
• loose tissues
• tissues with dual circulation (liver, lung, bowel)
• congested tissues
• can occur when flow is re-established to a site

White (occlusive)

• arterial
• more “solid” organs

Question 22

Factors that influence the development of an infarct:

Answer 22

1. Nature of vascular supply
2. Rate of development of the occlusion
3. Tissue vulnerability to hypoxia
4. Oxygen content of blood

Question 23

Definition: shock

Answer 23

Circulatory collapse with resultant hypo-perfusion and decreased oxygenation of tissue

Question 24

Causes of shock:

Answer 24

Decreased cardiac output

Widespread peripheral vasodilation

Question 25

4 major types of shock

Answer 25

1. Hypovolemic 2. Cardiogenic 3. Septic 4. Neurogenic

Question 26

Hypovolemic shock What is it? Causes?

Answer 26

Circulatory collapse resulting from acute reduction of circulating blood volume Caused by: 1. Severe hemorrhage or massive loss of fluid from the skin(injury, burns, trauma) 2. Loss of fluid from GI tract (vomiting, diarrhea)

Question 27

Cardiogenic shock What is it? Cause?

Answer 27

Circulatory collapse Resulting from: Pump failure of the left ventricle Most often caused by massive myocardial infarction

Question 28

Septic shock | What is it associated with?

Answer 28

Gram - infections Cause gram - endotoxemia * also occurs with gram + infections * TSS - staph aureus

Question 29

What is MODS?

Answer 29

Multiple organ dysfunction syndrome Can be an outcome of septic shock Characterized by systemic shut down of vital processes Requires major intervention

Question 30

Neurogenic shock is most often associated with ___

Answer 30

Severe trauma and Reactive peripheral vasodilation

Question 31

Stages of shock:

Answer 31

1. Nonprogressive (early) stage 2. Progressive stage 3. Irreversible stage

Question 32

``` Non progressive (early) stage of shock Characteristics ```

Answer 32

Compensatory mechanisms: - Increased heart rate - increased peripheral resistance Maintain perfusion of vital organs

Question 33

Progressive stage of shock | Characteristics

Answer 33

Tissue hypoperfusion Circulatory and metabolic imbalance -metabolic acidosis from lactic academia *compensatory mechanisms are no longer adequate

Question 34

Irreversible stage of shock | Characteristics

Answer 34

Organ damage and Metabolic disturbances are so severe that survival is not possible

Question 35

Morphologic manifestations of shock

Answer 35

ACUTE TUBULAR NECROSIS OF THE KIDNEY ``` Others: Brain necrosis Liver necrosis Fatty change in heart or liver Patchy mucosal hemorrhages in colon Depletion of lipid in adrenal cortex Pulmonary edema ```

Question 36

What is DIC?

Answer 36

Disseminated Intravascular Coagulation Widespread microvascular thrombi because of endothelial damage

Question 37

Causes of DIC

Answer 37

1. Major trauma (esp crush injuries) 2. Overwhelming infections (often gram -) 3. Obstetric complications 4. Mucin-secreting adenocarcinomas 5. Prostatic surgery 6. Venomous snake bites