Pathophysiology of Congestion and Oedema Flashcards
(36 cards)
What is congestive heart failure?
Failure of both sides of the heart
What causes vascular congestion?
Local/genarilised acute /chronic congestion
eg DVT (acute local) Hepatic cirrhosis (chronic local) Congestive Heart Failure (Generalised Acute)
What is exudate?
Exudate - think Emergency EXIT!
In infection/inflammation, basically when the endothelial becomes more “porous”/gappy and so fluid (inc. bigger moleules eg proteins) can flood out to go and fight
What is Transudate?
Transudate = Transferred fluid outside of vessel due to big pressure difference
Low protein/albumin/cells, high electrolytes and water.
What do starling’s forces say about fluid movement across capillaries?
Movement is proportional to the pressures into(oncotic - think proteins, not water) and out of (hydrostatic) capillary as well as the permeability of the vessel wall to fluid
How can disturbances in forces cause Oedema?
Increase in hydrostatic in comparison to oncotic pressure
What is Darcy’s law?
Blood flow = change in pressure/resistance
What is “congestion”?
THE BACKING UP OF BLOOD AND FLUID DUE TO A BLOCKAGE (usually)
Is congestion passive or active?
Passive
Is congestion primary or secondary?
sECONDARY
Congestion = acute or chronic?
Can be both
How does a dvt lead to ischemia?
DVT, blockage, decrease in pressure difference so drecrease in movement adnd flow of blood, tissue doesn’t recieve oxygen and so dies.
What can cause Hepatic Cirrhosis and what is it?
Viruses, eg HBV, HEP C and HEP B and alcohol
Causes fibrosis and scarring of the liver
How can Hepatic cirrhosis lead to chronic congestion?
Nodules of hepatocytes and Fibrosis, altered blood flow, blocked portal flow, congestion, increase in pressure and collateral circulation, chronic congestion
Why is there a haemorrhage risk in liver cirrhosis?
The increase in collateral circulation from the blocked portal vein, high pressure through small capillaries, can easily burst
Where are the main shunts around the portal circulation and what can be their complications?
Oesophageal varices, issue because if you eat something sharp, can puncture the increased collateral circulation and cause a major potentially fatal bleed.
Caput Medusae - cluster of swollen veins in your abdomen
Can you have Ciongestive Cardiac failure due to iscemic heart disease and valve disease?
Yes
How does Cardiac failure lead to congestion?
Cardiac failure = decreased CO = decreased Glomerular filtration rate (GFR), activation of renin-angiotensin-aldosterone system, increased Na and H2O retention, increased fluid in body, fluid overload in veins
Treatment for congestive cardiac failure?
Diuretics
What are the effects of congestive cardiac failure of the lungs?
Pulmonary oedema
What are the effects of congestive cardiac failure on the liver?
Central venous cogestion, right heart failure, blood dams back to the systemic circulation, increased JVP, hepatomegaly, peripheral oedema
Pc, Pi, 𝞹c, 𝞹i mean what?
Pc, = Capillary Hyrostatic pressure
Pi, = Interstital hydrostatic pressure
𝞹c = capillary oncotic pressure
𝞹i = interstial oncotic pressure
WHat is the pressure inside and outside a capillary on the arterial side?
Inside = 35mmHg Ouside = 25mmHg
WHat is the pressure inside and outside a capillary on the venous side? so which direction of blood flow?
Inside = 25mmHg Outside = 15mmHg