Haemodynamic Disorders
Q1. Define the term "Oedema" Oedema is the accumulation of excess fluid in the interstitial space of the body, leading to swelling and discomfort.
Q2. Describe the pathogenesis of oedema Oedema occurs due to an imbalance between capillary hydrostatic pressure and lymphatic drainage. This imbalance can be caused by:
- Increased capillary hydrostatic pressure (e.g., heart failure, liver cirrhosis)
- Decreased oncotic pressure (e.g., hypoalbuminemia)
- Increased vascular permeability (e.g., inflammation)
- Decreased lymphatic drainage (e.g., lymphedema)
Q3. Enumerate the differences between transudate and exudate Transudate:
- Low protein content
- High volume
- Due to increased hydrostatic pressure or decreased oncotic pressure
- Examples: liver cirrhosis, nephrotic syndrome
Exudate:
- High protein content
- Low volume
- Due to increased vascular permeability or inflammation
- Examples: pneumonia, cancer
Q4. Describe the etiopathogenesis of various types of oedema with its clinical correlation Types of oedema:
- Cardiac oedema (heart failure): increased capillary hydrostatic pressure
- Nephrotic oedema (nephrotic syndrome): decreased oncotic pressure
- Lymphatic oedema (lymphedema): decreased lymphatic drainage
- Pulmonary oedema (pulmonary edema): increased hydrostatic pressure or decreased oncotic pressure
Q5. Define the term "Active Hyperemia" Active hyperemia is a temporary increase in blood flow to a specific area of the body, usually in response to increased metabolic activity or injury.
Q6. Define the term "Venous congestion" or "Passive hyperaemia" Venous congestion is a condition where there is an increase in blood flow to a specific area of the body due to obstruction of the venous return, leading to edema and discomfort.
Q7. Describe the mechanisms involved in chronic venous congestion of different organs Chronic venous congestion can occur in various organs, including:
- Heart: due to heart failure or valvular disease
- Liver: due to liver cirrhosis or portal hypertension
- Lungs: due to pulmonary embolism or chronic obstructive pulmonary disease (COPD)
Q8. Explain morphology of Chronic Venous Congestion in Lung In the lungs, chronic venous congestion can lead to:
- Pulmonary edema: accumulation of fluid in the alveoli and interstitial space
- Pulmonary hypertension: increased pressure in the pulmonary arteries
- Right heart failure: increased pressure in the right ventricle
Q9. Define the terms "Haemorrhage", "Haematoma", "Ecchymosis", "Purpuras", "Petechiae"
- Haemorrhage: bleeding from blood vessels
- Haematoma: accumulation of blood in a specific area
- Ecchymosis: extravasation of blood into the skin or tissues
- Purpuras: small hemorrhages in the skin or mucous membranes
- Petechiae: small hemorrhages in the skin or mucous membranes
Q10. Define the term "Shock" Shock is a life-threatening condition characterized by inadequate blood flow to vital organs, leading to organ dysfunction and failure.
Q11. Classify shock based on aetiology Types of shock:
- Hypovolemic shock: due to blood or fluid loss
- Cardiogenic shock: due to heart failure
- Distributive shock: due to vasodilation or increased vascular permeability
- Obstructive shock: due to blockage of blood flow
Q12. Describe the pathogenesis of various types of shock Types of shock:
- Hypovolemic shock: decreased blood volume leads to decreased cardiac output
- Cardiogenic shock: heart failure leads to decreased cardiac output
- Distributive shock: vasodilation or increased vascular permeability leads to decreased blood pressure
- Obstructive shock: blockage of blood flow leads to decreased cardiac output
Q13. Describe the stages of shock Stages of shock:
- Stage 1: hypotension and decreased cardiac output
- Stage 2: organ dysfunction and failure
- Stage 3: multi-organ failure and death
Q14. Define the term "Thrombosis" ,“Thrombus" Thrombosis is the formation of blood clots inside blood vessels, while a thrombus is a blood clot that forms inside a blood vessel.
Q15. Enumerate the primary events in Thrombogenesis-Virchow’s triad Virchow's triad:
- Hypercoagulability: increased tendency to form blood clots
- Hypofibrinolysis: decreased ability to dissolve blood clots
- Endothelial damage: damage to the inner lining of blood vessels
Q16. Describe the etio-pathogenesis of thrombosis Thrombosis occurs due to an imbalance between pro-coagulant and anti-coagulant factors, leading to the formation of a blood clot.
Q17. Describe the morphologic features of thrombi Thrombi can be classified into:
- Venous thrombi: composed of red blood cells and fibrin
- Arterial thrombi: composed of platelets and fibrin
- Mixed thrombi: composed of both red blood cells and platelets
Q18. Describe the fate of thrombus Thrombus can:
- Dissolve and be removed by the body
- Organize and become a part of the blood vessel wall
- Embolize and cause blockage of blood flow to distant organs
Q19. Describe the clinical effects of various types of thrombi Types of thrombi:
- Pulmonary embolism: blockage of blood flow to the lungs
- Myocardial infarction: blockage of blood flow to the heart
- Stroke: blockage of blood flow to the brain
Q20. Define the term “Embolism”, “Embolus” Embolism is the blockage of blood flow to a specific area of the body, while an embolus is the object that causes the blockage.
Q21. Describe the various types of Emboli Types of emboli:
- Air embolism: blockage of blood flow by air
- Fat embolism: blockage of blood flow by fat droplets
- Amniotic fluid embolism: blockage of blood flow by amniotic fluid
- Thromboembolism: blockage of blood flow by a blood clot
Q22. Describe the etiopathogenesis of Pulmonary thromboembolism Pulmonary thromboembolism occurs due to the blockage of blood flow to the lungs by a blood clot.
Q23. Describe the consequences of pulmonary thromboembolism Consequences of pulmonary thromboembolism:
- Acute respiratory distress
- Cardiac arrest
- Death
Q24. Describe the pathogenesis of fat embolism Fat embolism occurs due to the blockage of blood flow to the lungs by fat droplets, usually after a traumatic injury.
Q25. Describe the pathogenesis of air embolism Air embolism occurs due to the blockage of blood flow to the lungs by air, usually after a medical procedure.
Q26. Describe the pathogenesis of amniotic fluid embolism Amniotic fluid embolism occurs due to the blockage of blood flow to the lungs by amniotic fluid, usually during childbirth.
Q27. Define the term “Ischaemia” Ischaemia is a condition characterized by inadequate blood flow to a specific area of the body.
Q28. Describe the etiopathogenesis of Ischaemia Ischaemia occurs due to:
- Decreased blood flow
- Increased blood pressure
- Increased metabolic demand
Q29. Describe the factors determining severity of Ischaemic injury Factors determining severity of ischaemic injury:
- Duration of ischaemia
- Extent of tissue damage
- Presence of pre-existing medical conditions
Q30. Define the term “Infarction” Infarction is the death of tissue due to inadequate blood flow.
Q31. Describe the etiopathogenesis of Infarction Infarction occurs due to:
- Prolonged ischaemia
- Increased metabolic demand
- Decreased blood flow
Q32. State the types of Infract Types of infarcts:
- Coagulative infarct: necrosis of muscle and liver cells
- Caseous infarct: necrosis of lung and spleen cells
- Fat infarct: necrosis of adipose tissue
- Hemorrhagic infarct: necrosis of tissue with bleeding. Haemodynamic Disorders ==========================
Oedema
- Definition: Oedema is the accumulation of excess fluid within the tissues of the body, leading to swelling.
- Pathogenesis: Oedema occurs due to an imbalance between the forces that drive fluid into the interstitial space (hydrostatic pressure) and those that drive fluid out (colloid osmotic pressure).
Differences between Transudate and Exudate
- Transudate: A clear fluid that accumulates in the interstitial space due to increased hydrostatic pressure or decreased colloid osmotic pressure.
- Exudate: A cloudy fluid that accumulates in the interstitial space due to inflammation, infection, or trauma.
Etiopathogenesis of Oedema
- Congestive Heart Failure: Increased hydrostatic pressure due to impaired cardiac function.
- Liver Disease: Decreased colloid osmotic pressure due to hypoalbuminemia.
- Nephrotic Syndrome: Decreased colloid osmotic pressure due to proteinuria.
- Lymphedema: Impaired lymphatic drainage.
Active Hyperemia
- Definition: An increase in blood flow to a specific area of the body due to increased metabolic demands.
- Mechanism: Increased oxygen and nutrient delivery to the affected area.
Venous Congestion
- Definition: An increase in blood volume in the veins due to impaired venous return.
- Mechanism: Backpressure in the veins leads to congestion in the affected organs.
Chronic Venous Congestion
- Liver: Hepatomegaly and ascites.
- Lungs: Pulmonary edema.
- Heart: Cardiomegaly and heart failure.
- Brain: Cerebral edema.
Morphology of Chronic Venous Congestion in Lungs
- Pulmonary edema: Fluid accumulation in the alveoli and interstitial space.
- Hyaline membranes: Thickening of the alveolar walls due to fluid and cellular infiltration.
Shock
- Definition: A condition characterized by inadequate blood flow and oxygen delivery to the tissues.
- Classification:
- Hypovolemic Shock: Decreased blood volume.
- Cardiogenic Shock: Impaired cardiac function.
- Distributive Shock: Impaired vascular tone.
- Obstructive Shock: Obstruction of blood flow.
Thrombosis
- Definition: The formation of a blood clot within a blood vessel.
- Mechanisms: Virchow's triad (blood flow, blood vessel wall, and blood composition).
Embolism
- Definition: The obstruction of blood flow due to a blood clot or foreign material.
- Types:
- Pulmonary Embolism: Clot in the pulmonary arteries.
- Fat Embolism: Fat globules in the bloodstream.
- Air Embolism: Air bubbles in the bloodstream.
- Amniotic Fluid Embolism: Amniotic fluid in the bloodstream.
Ischaemia
- Definition: A condition characterized by reduced blood flow and oxygen delivery to the tissues.
- Factors determining severity: Duration and extent of ischaemia.
Infarction
- Definition: The death of tissue due to prolonged ischaemia.
- Types:
- Myocardial Infarction: Heart tissue death.
- Cerebral Infarction: Brain tissue death.
- Renal Infarction: Kidney tissue death.
Infarct Types
- Coagulative Necrosis: Preservation of tissue architecture.
- Liquefactive Necrosis: Disintegration of tissue.
- Caseous Necrosis: Fungal-like tissue destruction.
- Fat Necrosis: Enzymatic breakdown of fat tissue.