Deep Vein Thrombosis (DVT)

DVT “Deep Vein Thrombosis”

• Most common symptom: new onset leg pain or leg swelling in one leg.
• Leg may turn more red or purple than the other leg.
• A blood clot in a deep vein.
• Deep veins are inside the muscle layer and run alongside the arteries.
• You can’t see a DVT and cannot  feel it with your hands.
• Doctors have high index of suspicion…If there is any doubt as to the cause of leg pain or swelling, an ultrasound is likely to be ordered.

3 Things Cause Blood To Clot
(VIRCHOW’S TRIAD)

Stasis – This is medical speak for slow blood flow.

• Sudden inactivity-long car ride, long plane trip, prolonged bedrest
• Restriction of blood flow in a vein from internal or external obstruction.

Injury

• Directly to the inner vein inning, getting hit or kicked
• to the body in general,   ‘the body’s clotting mechanism gets geared up”.

Hypercoagulability – Conditions that chemically make the blood clot easier than normal.

• Inherited problems: Factor V Leiden, Protein C deficiency, Protein S deficiency, Antithrombin III deficiency, Prothrombin Gene mutation.   
• Acquired factors: dehydration (less fluid in the blood), long periods of inactivity (hospitalization, surgery, long trips), polycythemia (body making too many red blood cells), thrombocythemia (too many platelets), and cancer. Antiphospholipid antibody.

Deep Vein Thrombosis (DVT) Diagnosis

• Leg ultrasound is the standard of care
• CT scans are also effective especially for looking at pelvic veins and for clots in the lungs
• Venogram  non filling area when dye is put into vein used infrequently for legs, more often used for pelvic veins.

Anticoagulation

• Slows or stops bloods ability to make clot.
• Keeps clot from growing.
• Does not dissolve clot.
  • IV Heparin – used in patients in hospital who may need its effect stopped quickly.
  • Lovenox – subcutaneous injection once or twice daily.
  • Coumadin – oral medication.
    • Blocks effects of vitamin K.
    • Affected by amt of Vit K in diet.
    • Hard to regulate proper dosage.
    • Blood work required to adjust dosage.
    • Once therapeutic, takes three days to wear off.
    • Reverse by Vitamin K or replacement of affected blood components.
    • Blood more prone to clotting than normal until proper therapeutic dose achieved.
    • Heparin or Lovenox also required while starting and stopping it (Bridging).
  • NOACs—New Oral Anticoagulants.
    • Don’t require blood monitoring.
    • Don’t require bridging.
    • Not affected by diet.
    • Short acting don’t need reversal agent.
    • Xarelto, Eliquis.

Thrombolysis

• Dissolves acute clot, < 2-3 weeks old.
• Tissue Plasminogen Activator (TPA) Alteplase™.
  • Systemic– drug goes into arm vein and throughout whole body. Higher risk of bleeding.
  • Catheter Directed—drug goes into multi side hole catheter placed directly into clot.
  • PharmacoMechanical—drug  and mechanical energy used simultaneously  to disrupt and evacuate clot.
  • Mechanical—open surgical removal of clot.

Inferior Vena Cava Filter

• An implanted device that traps blood clots before they can get to the heart.
• Used when anticoagulation can’t be used.
• Or patient unable to withstand any further heart or lung dysfunction.
• Ideally should be removed after no longer needed.
• Dissolvable filters are being tested.