Drainage & the Lymphatic System Flashcards
What are the three types of capillary ?
Continuous
Fenestrated
Discontinuous
What type of capillary is found in the blood brain barrier?
Continuous
What two mechanisms does clotting involve ?
1: Formation of the platelet plug
2: Formation of fibrin clot
What turns fibrinogen into fibrin ?
Thrombin
What does thrombin do to fibrinogen
Turns it into fibrin
What does the endothelium produce that inhibits platelet aggregation ?
Prostacylcins and NO
What do prostacyclins and NO do and where are they produced in ?
They inhibit platelet aggregation within the endothelium
What inhibits thrombin production and is produced by the endothelium ?
Tissue Factor Pathway Inhibitor (TFPI)
What does TFPI do ?
Inhibits thrombin production
What can bind to thrombin and deactivate it ?
Thrombomodulin
What does thrombomodulin do ?
Binds to thrombin and deactivates it
What does heparin do to thrombin ?
Deactivates it
What else can the endothelium secrete that will help to digests the clot ?
Tissue Plasminogen activator (t-PA)
This creates plasmin which digests the clot
Define bulk flow
Flow through the capillaries and the forces that act on them bringing water in and taking water out
What is bulk flow driven by ?
Hydrostatic pressure and osmotic pressure
What is filtration ?
When water moves from an area of high concentration in the capillaries to low concentration in the tissues
What is re-absorption ?
When water moves from an area of high concentration in the tissues to a low concentration in the capillaries
What is starlings law ?
The filtration and absorption of fluid between the capillary beds an the tissues depends top the balance between hydrostatic pressure and osmotic pressure
What is oedema ?
The accumulation of excess fluid in the interstitium
What are four causes of oedema ?
Lymphatic obstruction
Raised CVP
Hyperproteinaemia
Increased capillary permeability
