Deep vein thrombosis
Definition
A thrombus in a deep vein. Woo.
Epidemiology
It's common. You can get it. It's bad when you do get it because it can lead to a PE.
Pathophysiology
Essentially, keeping blood viscous is an active process. When veins are damaged, when blood stops moving it forms clots. (There's some clever physiology as to why that's true but I've forgotten it.)
These clots fly up the IVC and usually end up getting lodged in the lungs, causing a [[PE}} - that's why DVTs are so dangerous.
Risk Factors
There are lot so things that increase your risk of forming a DVT. They are basically split into the three categories: venous stasis, hypercoagubility and/or injury to vein intima. Each factor is either high, medium or low risk:
High risk
- Previous venous thrombo-embolism
- Recent surgery (particularly abdominal or lower limb)
- Cancer (particularly abdominal or lower limb)
- Immobilisiation
- Others: antiphospholipid syndrome, increased haematocrit, thrombphilia
Medium risk
Low risk
Pregnancy, COCP, tamoxifen, leg casts or other localised immobility, hyperlipidaemia, IBD (increased activity of a bunch of stuff involved in clotting)
Clinical Features
Classically, you get a unilateral, lower limb, painful, hot swelling. Skin discoloration, low-grade fever, superficial vein distention (due to the blood trying to find another way aroud) are also all clinical features.
The important differential is cellulitis.