Deep Venous Thrombosis (DVT)

Acute deep venous thrombosis (DVT) ranks with acute arterial occlusion as one of the most serious and dramatic vascular emergencies.

Factors contributing to thrombosis include:

1. Vessel wall,
2. Blood flow,
3. Coagulation characteristics.

A DVT most commonly appears in the lower extremity and is typically classified as being either:

1. Proximal (affecting the popliteal and thigh veins)
2. Or distal (affecting the calf veins).

Proximal deep venous thrombosis is the more dangerous form of lower extremity DVT because it is more likely to cause life-threatening PE.

Thrombosis in the deep veins of the leg is less symptomatic yet involves a far greater risk of embolism than thrombosis in the superficial veins.

Deep Vein Thrombosis Symptoms

Deep venous thrombosis Symptoms include:

1. Swelling in the extremity (primarily in the left leg at the vascular spur in the pelvic veins),
2. often associated with spontaneous pain in the groin,
3. pain radiating into the leg upon coughing or straining,
4. local blue discoloration of the skin,
5. in some cases elevated temperature and pulse are important signs.

A pulmonary infarction will often be the first clinical symptom, but typical early signs of deep venous thrombosis may also occur, these include: spots that are painful to palpation, extending from the sole of the foot (Payr) to, in certain cases, the groin (Rielander), and pain upon compression of the calf (Lowenberg) when a blood pressure cuff is applied and pumped up to 100 mm Hg (13.3 kPa). However, these thrombosis signs are nonspecific and should by no means be regarded as conclusive.

The unilateral edema that usually occurs develops gradually and begins in the malleolar region.

Additional characteristic findings include distended congested peripheral veins in the affected extremity (Pratt “warning” veins), evidence of superficial collateral veins, and an expanding edema, which is dependent on the size and localization of the thrombosis.

In patients with chronic venous disease, a number of test methods are helpful in evaluating the function of the deep veins and perforating veins.

See Also: Homans Sign Overview

What are the deep venous thrombosis warning signs?

Early signs of deep venous thrombosis include:

1. Tenderness to palpation on the medial aspect of the thigh (sartorius, gracilis).
2. Tenderness to palpation in the knee (muscular insertions and medial joint cavity).
3. Pain on compression of the calf (Lowenberg).
4. Pain in the calf on dorsi exion of the foot (Homans sign).
5. Tenderness to palpation.
6. Groin pain.
7. Tenderness to palpation along the adductor canal.
8. Pratt warning sign.
9. Meyer pressure points along the greater saphenous vein.
10. Pain in the sole of the foot, Payr sign: pressing or tapping the sole of the foot with the edge of the hand.

Certain patients are at increased risk for deep venous thrombosis:

Strong risk factors for DVT include:

1. fracture (pelvis, femur, and tibia),
2. hip or knee replacement:
3. major general surgery,
4. major trauma,
5. spinal cord injury.

See Also: Pelvic Fractures

Moderate deep venous thrombosis risk factors include:

1. arthroscopic knee surgery,
2. central venous lines,
3. chemotherapy,
4. congestive heart or respiratory failure,
5. hormone replacement therapy,
6. malignancy,
7. oral contraceptive therapy,
8. cerebrovascular accident,
9. pregnancy/ postpartum,
10. previous venous thromboembolism,
11. thrombophilia.

Weak deep venous thrombosis risk factors include:

1. bed rest greater than 3 days immobility due to sitting (e.g., prolonged air travel),
2. increasing age,
3. laparoscopic surgery,
4. obesity,
5. pregnancy/ antepartum,
6. varicose veins.

A recent study indicated that up to 60% of patients undergoing total hip replacement surgery may develop a deep venous thrombosis without preventative treatment.

Musculoskeletal conditions that may mimic symptoms associated with deep venous thrombosis include:

1. hematoma,
2. myositis,
3. tendinitis,
4. Baker’s cyst,
5. synovitis,
6. osteomyelitis,
7. tumors.

Prevention & Treatment of Deep Venous Thrombosis

Methods of prevention may be classified as pharmacological and nonpharmacological.

Pharmacological prevention includes:

1. anticoagulant drugs such as low-dose Coumadin (warfarin),
2. low molecular weight heparin LMWH,
3. adjusted dose heparin,
4. heparinantithrombin III combination.

These drugs work by altering the body’s normal blood-clotting process.

Second tier drugs include dextran, aspirin, and low-dose subcutaneous heparin.

Nonpharmacological prevention attempts to counteract the effects of immobility, including:

1. calf and foot/ ankle exercises,
2. compression stockings.

A recent study has shown that substantial hyperemia (a mean 22% increase in venous outflow) occurs after the performance of active ankle pumps for 1 minute, and venous outflow remains greater than the baseline level for 30 minutes reaching a maximum 12 minutes after these exercises.

Although this does not provide sufficient evidence that exercise alone prevents deep venous thrombosis, it suggests that the active ankle pump does influence venous hemodynamics.

Finally, inferior vena cava (IVC) filters and Greenfield filters may be employed with a patient who has a contraindication to anticoagulation, previous complications with anticoagulants, or if anticoagulants have proved ineffective in the past.

References & More

1. Haeger K. Problems of acute deep venous thrombosis. I. The interpretation of signs and symptoms. Angiology. 1969 Apr;20(4):219-23. doi: 10.1177/000331976902000406. PMID: 5778113. Pubmed
2. Weinmann EE, Salzman EW. Deep-vein thrombosis. N Engl J Med. 1994 Dec 15;331(24):1630-41. doi: 10.1056/NEJM199412153312407. PMID: 7772110. Pubmed