Pathophysiology Of Oedema Flashcards
What is oedema?
Accumulation of abnormal amounts of fluid in the extravascular compartment
What is peripheral oedema?
What is effusions?
Peripheral oedema is increased interstitial fluid in tissues
Effusions is fluid collections in body cavities
What is efffusions in the abdominal cavity called?
Ascites
What is transudate odema caused by?
Alterations in the haemodynamic forces which act across the capillary wall
What is exudate oedema caused by?
Part of the inflammatory provess due to an increase in vascular permeability
What type of oedema had a high protein/albumin content?
Exudate
Decrive how left ventricular failure causes pulmonary oedem.
The left arial pressure increases so there is a passive retrograde flow to the pulmonary veins capillaries and arteries
This increases pulmonary vascular pressure
There is an increase in pulmonary blood volume
Increase in pulmonary circulation cauzes an increase in filtration and pulmonary oedema
(There is much greater hydrostatic pressure driving fluid out of the vessels than the oncotic pressure driving fluid into the vessels = oedema)
Decribe the pathophysiology of peripheral oedema from right heart failure.
RHF cannot empty the RV in systole so causes blood to be retained in systemic veins resulting in increased pressure in capillaries —> increased filtration = peripheral oedema
Where does oedema occur due to congestive heart failure?
Because both centricles fail in CHF then blood backs up in both systemic and pulmonary circulations resulting in peripheral and pulmonary oedema at the same time
Describe how breast cancer may cause lymphoedema.
Breast cancer treatment may require radiotherapy to the chest
This can cause fibrosis in the lymphatic system of the axilla area resulting in decreased lymph fluid outflow and resulting oedema of the upper limb
What causes hydrostatic upset in the lymphatic circulation which can cauze lymphoedema?
Lymohatic obstruction
Why does abnormal renal function cauze oedema?
Abnormal renal function causes salt and water retension
What type of oedema is low protein oedema?
Transudate
How does low protein cause oedema?
Hypoalbuminaemia causes a decrease in oncotic pressure therefore reduces the driving force of fluid into the vessels,
resulting in more fluid in the extravasular space
What can be the causes of hypoalbuminaemia which can cause oedema?
Malnutrition Hepatic cirrhosis (liver unable to synthesise protein) Nephrotic syndrome (leaky renal glomerular basement membrane results in proteins being lost in the urine)
