Venous

DVT/thrombophlebitis ➔ Venous insufficiency/PE

Superficial veins (surface, can usually see) drain into deep veins (deep in-between muscles)
- Skeletal muscle forces blood upward and valves prevent blood from backward flow
Clots develop in deep veins ➔ thrombus ➔ ↓ blood flow or can embolize to pulmonary circulation
- Plasmin breaks down Fibrin (in clot) ➔ D-dimer

Virchow Triad
1. Hyper-coagulability - cancer, pregnancy, factor V Leiden, AT deficiency
2. Vascular injury - sub-endothelial exposure of collagen
3. Venous stasis - immobilized (bed-bound, long trips sitting), locally applied heat (vasodilation ➔ slowed flow)

Unilateral & localized pain with swelling/feeling tight, warmth, erythema
- MC in left calf
- DVT ➔ distended superficial veins
± discoloration, ± fever from inflammatory cytokines
Pulmonary embolism: dyspnea, CP, dizziness, low sat despite supplemental O2

Right iliac vein compresses left iliac vein ➔ ↑ risk of DVT in LLE
Homan sign may involve upward pressure on calf but how could you tell the difference between Homan or Meyer?
- Homan sign isn't really helpful (and people love telling you this)

D-Dimer if Wells' score < 3 (r/o DVT in low-moderate PTP)
US if Wells' score > 3
- Compression US (CUS) with Doppler is diagnostic test of choice
  - Thrombosed veins are "non-compressible" on US
- Venous duplex US has less accuracy than CUS but can be done
  - Contrast venography was gold standard

Pre-Test Probability (Wells' score) > 3 points = high PTP

1 Point each:

Minus 2 points: Alternative dx as likely

D-dimer is elevated in a lot of conditions (not specific) and is used to ↓ unnecessary imaging
- From a test question perspective... I'd probably pick US
CUS: pressure applied with probe to a non-thrombosed vein lumen will be occluded on application (Non-thrombosed vein is compressible)
Migrating thrombophlebitis ➔ think cancer workup
Any VTE issue ➔ think hypercoag workup (preg, lupus)

Initial anticoagulation (10d) then long term anticoagulation (10d - 3mo)
- Low molecular weight heparin (LMWH) alone (SQ injection): cancer, pregnancy, liver dz
- LMWH + warfarin
- LMWH 5-10d then DOACs (dabigatran or edoxaban)
- DOACs (dabigatran or edoxaban) alone
Recurrent VTE or absolute CI to anticoagulation (recent surgery, hemorrhagic stroke, active bleeding) gets IVC filter

LMWH potentiates the natural anticoagulant in body (antithrombin)
- No monitoring needed
- Antidote: Protamine sulfate
Warfarin should not be given alone for initial anticoag because it takes too long to start working and ↑ risk of clotting when starting
- Monitor PT, INR to therapeutic level: 2-3
- Antidote: Vitamin K, fresh frozen plasma (FFP) for severe bleeding
Dabigatran reversal with idarucizumab, no antidote for edoxaban
IVC filter will not ↓ PE if thrombus origin is cardiac or renal/upper extremity veins

Consider VTE ppx in hospitalized medical pts with ↑ risk of VTE

+ 3 points

+ 2 points

+ 1 points

Malfunctioning valves ➔ ↑ venous pressure ➔ fluid accumulation ➔ skin changes and ulcer formation
↑ pressure ➔ reflux into superficial veins ➔ dilation ➔ varicose veins
RF: HX of thrombosis, ↑ BMI/ ↓ PA, pregnancy, smoking

Pain (worse with standing) relieved with elevation/walking
Stasis dermatitis: itchy, scaly, crusty, brown/purple, weeping
- RBC breakdown ➔ hemosiderin deposits in skin ➔ hyper-pigmented skin
- Atrophy ➔ fibrotic tissue without capillaries ➔ hypopigmented plaques (atrophie blanche)
Dependent pitting edema
Medial malleolus ulcers

Compression stocking, exercise, leg elevation, wound care
- Cosmetic ablation for varicose veins
Wound care

Superficial vein thrombus ➔ palpable cord, tenderness along vein course, warmth, erythema
- IV catheter, factor 5 Laiden MCC, pregnancy, varicose veins
DX
- R/o DVT with US
TX sx with NSAIDs, warm compress, elevation, encourage ambulation
- Evaluate underlying cause and consider anticoagulation to prevent DVT

Next: Vasculitis