Circulation Anomlies

Question 1

Circulation control

Answer 1

Autonomic nervous system (via Medulla Oblongata)

Vessel caliber altered via smooth muscle control

Question 2

Ischaemic heart disease

Answer 2

Reduced blood supply = reduced oxygen

Question 3

Thrombogenesis - Virchow’s Triad

Answer 3

1. Alteration to bloodflow
   - Stasis = slow rate of bloodflow
   - Alteration of vessel size
2. Damage to endothelial wall = sites for clotting
3. Change in blood composition = coagulation

Question 4

Thrombosis sequels

Answer 4

Fibrinolysis = small thrombi removed via fibrolytic system
Embolism = part of thrombus detaches
Organisation = neo capillaries at thrombo attachement
Calcification = absence of organisation leads to Ca2+ deposition and thrombo-shinkage
Incorporation = aka mural thrombus, endothelial coverage on vessel wall, formation of artheroma

Question 5

Emboli state

Answer 5

Solid = tumor, bacteria or parasite
Gaseous = O2 or N2 bubbles
Liquid = Fat or amniofluid

Question 6

Infarction

Answer 6

Area of necrosis due to ischemia

More likely from arterial obstruction than venous occlussion

Question 7

Pulmonary Thrombo-embolism

Answer 7

Origin = DVT in lower limb
Small = pulmonary hypertension
Moderate = Infarctions
Large = pulmonary arterial blockage - sudden death

Question 8

Cyanosis

Answer 8

a bluish discoloration of the skin due to poor circulation or inadequate oxygenation of the blood

Question 9

H2O control

Answer 9

Intracellular fluid = Fluid with in cells (high in K+)

Extracellular fluid = Interstitial fluid + plasma (high in Na+ + Ca++)

Question 10

H2O control - 4 forces

Answer 10

1. Capillary filtration pressure
2. Capillary colloidal pressure
3. Interstitial fluid pressure
4. Tissue colloidal osmotic pressure

Question 11

Capillary filtration pressure

Answer 11

drives fluid out of the capillary

Question 12

Capillary colloidal pressure

Answer 12

orm of osmotic pressure exerted by proteins

Pulls water back into capillary

Question 13

Interstitial fluid pressure

Answer 13

Opposes movement out of capillary

Question 14

Tissue colloidal osmotic pressure

Answer 14

osmotic pressure exerted by proteins

pull water out of capillary

Question 15

Mechanisms controlling fluid movement

Answer 15

-Fluid intake
-Kidney filtration integrity
-Hormone activity
+Aldosterone = increases Na++ reabsorption in kidney (H20 retention - opposed by Cardiac Homone)
+Anti-diuretic hormone - increases reabsorption of H2O

Question 16

Causes of Oedema

Answer 16

• increased hydrostatic pressure (heart failure with increased venous pressure)
• Decreased Colloidal presssure (low albumin)
• Increased vascular permeability
• Lymphatic obstruction (Iatrogenic Masectomy Sx)

Question 17

Oedema

Answer 17

Local = atopy or injury
General = congestive heart failure (venous congestion)

Question 18

Protein oedema

Answer 18

Low content = Transudate - applies to excessive venous pressure
High content = Exudate - applies to lymphatic obstruction

Question 19

Shock

Answer 19

vital functions of body depressed due to:

• severe and acute reduction of cardiac output
• reduction of circulating blood volume
• results in hypotension, hyperventilation + reduced consciousness

Question 20

Causes of shock

Answer 20

1 Hypovolemic shock - loss of blood volume
2 Cardiogenic pump failure - extensive myocardial infarction
3 Bacterial - sepsis
4. Anaphylactic shock - severe hypersensitivity reaction

Question 21

Consequences of shock

Answer 21

low cardiac output
hypotension
impaired tissue perfusion
cellular hypoxia

Question 22

Stages of shock

Answer 22

Non-progressive
Progressive
Irreverible