Haemodynamic disorders

Question 1

What does fluid homeostasis require? 3

Answer 1

• Vessel wall integrity
• Osmolarity (solutes in plasma e.g. ions, proteins, urea, sugars)
• Maintenance of intravascular pressure (blood volume, smooth muscle tone)

Question 2

What is haemodynamics?

Answer 2

The flow of blood through the circulatory system.

Question 3

What factors are required for fluid homeostasis?

Answer 3

Vessel wall integrity, osmolarity, and maintenance of intravascular pressure.

Question 4

What is edema?

Answer 4

Abnormally increased fluid in the interstitial tissue space.

Question 5

What causes edema? 6

Answer 5

• Increased vascular volume/pressure
• decreased plasma protein content
• endothelial dysfunction
• lymphatic obstruction
• sodium retention
• inflammation.

Question 6

What is hydrostatic pressure?

Answer 6

Pressure exerted by fluid that drives fluid from blood vessels into tissues.

Question 7

What is colloid osmotic pressure?

Answer 7

Pressure that pulls water back into blood vessels due to the higher concentration of proteins like albumin.

Question 8

What is the cause of pulmonary edema?

Answer 8

Increased hydrostatic pressure in the lungs, leading to fluid buildup.

Question 9

What is hyperaemia?

Answer 9

Adaptive increase in blood volume in tissues due to environmental changes.

Question 10

What causes vascular congestion?

Answer 10

Impaired venous return, leading to increased venous pressure.

Question 11

What is thrombosis?

Answer 11

Formation of a blood clot within a vessel, often caused by endothelial injury, abnormal blood flow, or hypercoagulability.

Question 12

What is the main cause of arterial thrombosis?

Answer 12

High shear flow and platelet-rich formation, often around ruptured atherosclerotic plaques.

Question 13

What is atherosclerosis? Caused by what? 2

Answer 13

Chronic inflammatory disease of the arterial wall caused by fatty lesions and lipid buildup.

Question 14

What are the types of shock? 6

Answer 14

Cardiogenic, hypovolemic, obstructive, neurogenic, septic, and anaphylactic shock.

Question 15

What is septic shock?

Answer 15

Shock caused by a systemic infection, often bacterial, leading to vasodilation and reduced blood pressure.

Question 16

What is the clinical significance of hemorrhage?

Answer 16

Loss of blood can lead to hypovolemic shock or iron deficiency if recurrent.

Question 17

What is petechiae?

Answer 17

Minute hemorrhages (1-2mm) in the skin or mucosa due to thrombocytopenia or increased capillary pressure.

Question 18

What causes purpura?

Answer 18

Small hemorrhages (3-10mm) due to trauma or vasculitis.

Question 19

What is the cause of ecchymosis (bruising)? 3

Answer 19

Subcutaneous hemorrhage caused by trauma, platelet or clotting factor deficiencies.

Question 20

What is a mural thrombus?

Answer 20

A thrombus that forms along the wall of a blood vessel without fully occluding it.

Question 21

What is an occlusive thrombus?

Answer 21

A thrombus that fully occludes a blood vessel, preventing blood flow.

Question 22

What is the difference between arterial and venous thrombosis?

Answer 22

Arterial thrombosis forms in high shear flow and is platelet-rich; venous thrombosis forms in low shear flow and is fibrin and erythrocyte-rich.

Question 23

What is an atheroma?

Answer 23

A fatty plaque that forms in the arterial wall during atherosclerosis, consisting of lipids, foam cells, and inflammatory cells.

Question 24

What happens during the plaque rupture stage of atherosclerosis?

Answer 24

The fibrous cap of the plaque breaks, exposing thrombogenic material, leading to thrombosis (atherothrombosis).

Question 25

What is the first visible sign of atherosclerosis?

Answer 25

Fatty streak

Question 26

Which type of lipoprotein gets trapped in the sub-endothelial space during the initiation of atheroma formation?

Answer 26

Low-density lipoprotein (LDL)

Question 27

Which cells transform into foam cells during atheroma formation?

Answer 27

Macrophages

Question 28

What is the main characteristic of plaque progression in atherosclerosis?

Answer 28

Formation of a fibrous cap

Question 29

Which event is most likely to trigger atherothrombosis?

Answer 29

Plaque rupture

Question 30

Which of the following is the first stage in the development of an atheroma?

Answer 30

Fatty streak formation

Question 31

What are common complications of atherosclerosis? 5

Answer 31

Heart attack, stroke, peripheral artery disease, chronic kidney disease, and aneurysm.

Question 32

What is the primary cause of pulmonary embolism?

Answer 32

Deep vein thrombosis (DVT) in the legs.

Question 33

What is ischemia?

Answer 33

Insufficient blood supply to tissues, leading to a lack of oxygen and nutrients.

Question 34

What is hypoxia?

Answer 34

A deficiency of oxygen in tissues, typically caused by ischemia.

Question 35

What is the difference between a true aneurysm and a false aneurysm?

Answer 35

A true aneurysm involves all three layers of the vessel wall; a false aneurysm is a contained hematoma formed outside the vessel wall.

Question 36

What is a fusiform aneurysm?

Answer 36

An aneurysm where the blood vessel bulges evenly on all sides.

Question 37

What is a saccular aneurysm?

Answer 37

An aneurysm where the blood vessel bulges on one side.

Question 38

What are the common causes of cardiogenic shock? 3

Answer 38

Myocardial damage (e.g., heart attack), arrhythmias, or pulmonary embolism.

Question 39

What is hypovolemic shock?

Answer 39

Shock caused by loss of blood or plasma, such as from hemorrhage or severe burns.

Question 40

What is obstructive shock?

Answer 40

Shock caused by an obstruction to blood flow, such as in a massive pulmonary embolism.

Question 41

What causes neurogenic shock?

Answer 41

Severe damage to the central nervous system, causing loss of vasoconstriction and pooling of blood.

Question 42

What is the cause of septic shock?

Answer 42

A systemic infection, often bacterial, that leads to widespread vasodilation and hypotension.

Question 43

What is anaphylactic shock?

Answer 43

Severe allergic reaction that causes widespread vasodilation and decreased blood pressure due to the release of inflammatory mediators.

Question 44

What is the pathophysiology of septic shock? cause what 3 things?

Answer 44

Bacterial components activate the immune system, causing widespread vasodilation, vascular leakage, and coagulation abnormalities.

Question 45

What is the mortality rate for septic shock?

Answer 45

40-55%, depending on the severity of the shock.

Question 46

Which bacterial component is responsible for activating macrophages and neutrophils in septic shock?

Answer 46

Lipopolysaccharide (LPS)

Question 47

Which cytokines are primarily released during septic shock?

Answer 47

Interleukin-1 (IL-1) and Tumor Necrosis Factor-alpha (TNFα)

Question 48

What is the effect of endothelial cell activation in septic shock?

Answer 48

Systemic vasodilation and hypotension

Question 49

Which of the following is a major consequence of septic shock?

Answer 49

Increased blood clotting and thrombosis

Question 50

Which of the following complications is associated with severe septic shock?

Answer 50

Multi-organ dysfunction syndrome (MODS)

Question 51

what does a ruptured plaque cause? 3

Answer 51

* Acute narrowing of the vessel lumen * Chronic occlusion (due to the growing plaque) * Embolism (of ruptured plaque)