Deep Venous Thrombosis




Abstract


Deep venous thrombosis (DVT) is a manifestation of venothromboembolism and is a global cause of morbidity and mortality. DVT is a thrombus formation of deep veins most commonly seen in the lower extremities. Diagnosis is made by a history and physical examination in combination with diagnostic testing and imaging modalities. Treatment is tailored to the disease severity, with the mainstay of treatment being anticoagulation therapy with unfractionated heparin, low-molecular-weight heparin, fondaparinux, or direct oral anticoagulants. Inferior vena caval filters and surgical removal can also be considered as treatment if contraindications exist to pharmacologic management.




Keywords

Anticoagulation therapy, deep vein thrombosis, direct oral anticoagulants, IVC filter, low-molecular-weight heparin

 



















































































































































Synonyms



  • Venous thromboembolism



  • Blood clot



  • Thrombophlebitis



  • Phlebothrombosis

ICD-10 Codes
I80.201 Phlebitis and thrombophlebitis of unspecified deep vessels of right lower extremity
I80.202 Phlebitis and thrombophlebitis of unspecified deep vessels of left lower extremity
I80.203 Phlebitis and thrombophlebitis of unspecified deep vessels of lower extremities, bilateral
I80.209 Phlebitis and thrombophlebitis of unspecified deep vessels of unspecified lower extremity
I82.409 Acute embolism and thrombosis of unspecified deep veins of unspecified lower extremity
I82.4 Acute embolism and thrombosis of deep veins of lower extremity
I82.40 Acute embolism and thrombosis of unspecified deep veins of lower extremity
I82.401 Acute embolism and thrombosis of unspecified deep veins of right lower extremity
I82.402 Acute embolism and thrombosis of unspecified deep veins of left lower extremity
I82.403 Acute embolism and thrombosis of unspecified deep veins of lower extremity, bilateral
I82.41 Acute embolism and thrombosis of femoral vein
I82.411 Acute embolism and thrombosis of right femoral vein
I82.412 Acute embolism and thrombosis of left femoral vein
I82.413 Acute embolism and thrombosis of femoral vein, bilateral
I82.419 Acute embolism and thrombosis of unspecified femoral vein
I82.42 Acute embolism and thrombosis of iliac vein
I82.421 Acute embolism and thrombosis of right iliac vein
I82.422 Acute embolism and thrombosis of left iliac vein
I82.423 Acute embolism and thrombosis of iliac vein, bilateral
I82.429 Acute embolism and thrombosis of unspecified iliac vein
I82.43 Acute embolism and thrombosis of popliteal vein
I82.431 Acute embolism and thrombosis of right popliteal vein
I82.432 Acute embolism and thrombosis of left popliteal vein
I82.433 Acute embolism and thrombosis of popliteal vein, bilateral
I82.439 Acute embolism and thrombosis of unspecified popliteal vein
I82.44 Acute embolism and thrombosis of tibial vein
I82.441 Acute embolism and thrombosis of right tibial vein
I82.442 Acute embolism and thrombosis of left tibial vein
I82.443 Acute embolism and thrombosis of tibial vein, bilateral
I82.449 Acute embolism and thrombosis of unspecified tibial vein
I82.49 Acute embolism and thrombosis of other specified deep vein of lower extremity
I82.491 Acute embolism and thrombosis of other specified deep vein of right lower extremity
I82.492 Acute embolism and thrombosis of other specified deep vein of left lower extremity
I82.493 Acute embolism and thrombosis of other specified deep vein of lower extremity, bilateral
I82.499 Acute embolism and thrombosis of other specified deep vein of unspecified lower extremity
I82.4Y Acute embolism and thrombosis of unspecified deep veins of proximal lower extremity
I82.4Y1 Acute embolism and thrombosis of unspecified deep veins of right proximal lower extremity
I82.4Y2 Acute embolism and thrombosis of unspecified deep veins of left proximal lower extremity
I82.4Y3 Acute embolism and thrombosis of unspecified deep veins of proximal lower extremity, bilateral
I82.4Y9 Acute embolism and thrombosis of unspecified deep veins of unspecified proximal lower extremity
I82.4Z Acute embolism and thrombosis of unspecified deep veins of distal lower extremity
I82.4Z1 Acute embolism and thrombosis of unspecified deep veins of right distal lower extremity
I82.4Z2 Acute embolism and thrombosis of unspecified deep veins of left distal lower extremity
I82.4Z3 Acute embolism and thrombosis of unspecified deep veins of distal lower extremity, bilateral
I82.4Z9 Acute embolism and thrombosis of unspecified deep veins of unspecified distal lower extremity




Definition


Venous thromboembolism (VTE) is a major cause of mortality and morbidity and is manifested by deep venous thrombosis (DVT) and pulmonary embolism. This chapter is limited to the discussion of DVT. DVT occurs when a fibrin clot abnormally occludes a vein in the deep venous system, predominantly in the lower extremities. The prevailing theory explaining the development of DVT is known as Virchow triad, which includes alterations in blood flow (stasis), vascular endothelial injury, and hypercoagulation disorder. The risk for development of DVT varies according to specific characteristics of the patient, the medical condition, or the surgical procedure ( Table 128.1 ). Conditions that may increase the risk for development of DVT are advanced age, morbid obesity, varicose veins, prolonged immobility, pregnancy, malignant disease, stroke, inflammatory bowel disease, congestive heart failure, and previous DVT. Certain hereditary conditions may also predispose to development of DVT, such as deficiencies in protein C and protein S and familial thrombophilia. Acquired deficiencies of the natural anticoagulant system include antibodies directed against antiphospholipid and heterozygous factor V Leiden mutations.



Table 128.1

Risk Factors for Deep Venous Thrombosis












Patient Factors Diseases Procedures
Age > 40 years
Obesity
Varicose veins
Prolonged immobilization
Pregnancy
High-dose estrogen therapy
Tamoxifen
Bevacizumab
Previous deep venous thrombosis
Thrombophilia
Antithrombin III, protein C, protein S deficiency
Antiphospholipid antibody, lupus anticoagulant
Malignant disease
Major medical illness
Trauma
Spinal cord injury
Paralysis
Pelvic surgery
Lower limb orthopedic surgery
Neurosurgery

Modified from Sokolof J, Knight R. Deep venous thrombosis. In: Frontera WR, Silver JK, Rizzo TD Jr, eds. Essentials of Physical Medicine and Rehabilitation , 2nd ed. Philadelphia: WB Saunders; 2008.


Patients can be categorized according to their risk for development of DVT on the basis of the type of surgical procedure, with orthopedic patients carrying the highest risk ( Table 128.2 ). It is believed that orthopedic procedures carry such a high risk for DVT because the mechanical destruction of bone marrow during most orthopedic procedures causes intravasation of marrow cells and cell fragments and elevations of plasma tissue factor. Plasma tissue factor is a potent trigger of blood clotting. It is found in high concentrations in bone marrow and the adventitia surrounding the major blood vessels and the brain. Surgical trauma to these structures places neurosurgical patients at great risk for development of DVT. Following neurosurgery, the incidence of DVT has been reported to be as high as 50%. Risk factors that increase the rates of DVT in neurosurgery patients include intracranial surgery, malignant tumors, duration of the surgery, and presence of paresis or paralysis of the lower limbs. Patients can remain in a hypercoagulable state up to 5 weeks postoperatively. In addition to surgical patients, victims of orthopedic and neurologic trauma are at great risk for development of DVT, especially if long bone fracture or paralysis is sustained. Patients who suffer injury to the spinal cord are at high risk for DVT because of stasis and hypercoagulability.



Table 128.2

Risk Categories of Venous Thromboembolism in Surgical Patients Without Prophylaxis





































































Risk Category Calf DVT Proximal DVT Fatal PE
High 40%–80% 10%–30% 1%–5%
Major orthopedic surgery of the lower limb
Major general surgery in patients > 40 years with cancer or recent DVT or PE
Multiple trauma
Thrombophilia
Moderate 10%–40% 2%–10% 0.1%–0.8%
General surgery in patients > 40 years that lasts 30 minutes or more without additional risk factors
General surgery in patients < 40 years receiving estrogen or with a history of DVT or PE
Emergency cesarean section in women > 35 years
Low <10% <1% <0.01%
Minor surgery (i.e., < 30 minutes in patients > 40 years without additional risk factors)
Uncomplicated surgery in patients < 40 years without additional risk factors

DVT, Deep venous thrombosis; PE, pulmonary embolism.




  • From Sokolof J, Knight R. Deep venous thrombosis. In: Frontera WR, Silver JK, Rizzo TD Jr, eds. Essentials of Physical Medicine and Rehabilitation, 2nd ed. Philadelphia: WB Saunders; 2008.



  • Modified from Bounameaux H. Integrating pharmacologic and mechanical prophylaxis of venous thromboembolism. Thromb Haemost. 1999;82:931–939.





Symptoms


Venous thrombosis often occurs asymptomatically. Symptoms of DVT may include ipsilateral lower extremity edema, fever, extremity warmth, and pain. Symptoms do not rule in or rule out DVT, but they can serve as a trigger for further diagnostic inquiry.




Physical Examination


The classic signs of DVT are tenderness, ipsilateral swelling, and warmth. A palpable cord can sometimes be felt, indicative of a thrombosed vein. In the past, emphasis was placed on the presence of Homan’s sign and calf tenderness in making a clinical diagnosis of DVT. However, these physical examination findings have been found to be nonspecific with poor positive predictive values. Significant asymmetric calf edema is an important sign and can be determined by taking the circumferential measurement of the calf 10 cm below the tibial tuberosity. A 3-cm difference in calf girth is considered a significant clinical difference. When it is massive, the swelling can obstruct not only venous outflow but also arterial inflow, leading to phlegmasia cerulea dolens as a result of ischemia. Here, the leg is usually blue and painful.


As with symptoms, physical examination findings are neither sensitive nor specific. In more than 50% of the instances of DVT, physical examination findings are normal.




Functional Limitations


DVT rarely causes functional compromise, except calf pain during walking. Absolute bed rest is generally not indicated, and early walking is safe in patients with acute DVT and may help reduce acute symptoms. However, patients should suspend their lower extremity exercise program until they are fully anticoagulated.




Diagnostic Studies


The Wells clinical prediction rule ( Table 128.3 ) is a score based on a group of clinical characteristics that are useful in estimating the pretest probability of DVT. High-quality evidence exists to support the validity of this rule, and its use is recommended as a practice guideline by the American Academy of Family Physicians and the American College of Physicians. It is easily implemented before more definitive testing is performed on patients.



Table 128.3

Wells Prediction Rules: Clinical Evaluation Table for Predicting Pretest Probability of Deep Venous Thrombosis


































Clinical Characteristic Score
Active cancer (treatment ongoing, within previous 6 months, or palliative) 1
Paralysis, paresis, or recent plaster immobilization of the lower extremities 1
Recently bedridden > 3 days or major surgery within 12 weeks requiring general or regional anesthesia 1
Localized tenderness along the distribution of the deep venous system 1
Entire leg swollen 1
Calf swelling 3 cm larger than asymptomatic side (measured 10 cm below tibial tuberosity) 1
Pitting edema confined to the symptomatic leg 1
Collateral superficial veins (nonvaricose) 1
Alternative diagnosis at least as likely as deep venous thrombosis −2

Clinical probability: low, ≤ 0; intermediate, 1–2; high, ≥ 3. In patients with symptoms in both legs, the more symptomatic side is used.

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Jul 6, 2019 | Posted by in PHYSICAL MEDICINE & REHABILITATION | Comments Off on Deep Venous Thrombosis

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