Edema, Lower Extremity

Essentials of Diagnosis

• Inquire about

  • History of venous thromboembolism

  • Symmetry of swelling

  • Pain

  • Change with dependence

  • Skin findings: hyperpigmentation, stasis dermatitis, lipodermatosclerosis, atrophie blanche, ulceration

General Considerations

• Lower extremities can swell in response to

  • Increased venous or lymphatic pressures

  • Decreased intravascular oncotic pressure

  • Increased capillary leak

  • Local injury or infection

• Chronic venous insufficiency is the most common cause of chronic lower extremity edema, affecting up to 2% of the population

Symptoms and Signs

Unilateral edema

• Deep venous thrombosis

  • Life-threatening

  • History of cancer, recent limb immobilization, or confinement to bed for at least 3 days following major surgery within the past month are suggestive clues

  • Adults with varicose veins have a significantly increased risk of DVT

  • Postphlebitic syndrome with valvular incompetence seen in patients with lower extremity swelling and inflammation in a limb recently affected by DVT

• Other causes of a painful, swollen calf

  • Cellulitis

  • Musculoskeletal disorders (Baker cyst rupture ["pseudothrombophlebitis"])

  • Gastrocnemius tear or rupture

  • Calf strain or trauma

  • Left common iliac vein compression (May-Thurner syndrome)

  • Other sites of nonthrombotic venous outflow obstruction, such as the inguinal ligament, iliac bifurcation, and popliteal fossa

• Swelling of the ankle can be a manifestation of Charcot neuropathic osteoarthropathy

Bilateral edema

• Bilateral involvement and significant improvement upon awakening

  • Favor systemic causes (eg, venous insufficiency)

  • Can be presenting symptoms of volume overload (HF, cirrhosis, kidney disease [eg, nephrotic syndrome])

• Sensation of "heavy legs" is the most frequent symptom, followed by itching

• Brawny, fibrotic skin changes; predisposition toward skin ulceration, particularly in the medial malleolar area

• Lymphedema and lipedema

• Pain is uncommon

• Medications that may cause lower extremity swelling

  • Calcium channel blockers (particularly felodipine and amlodipine)

  • Pioglitazone

  • Gabapentin

  • Minoxidil

• Pelvic congestion syndrome worsens symptoms of chronic venous symptoms of the lower extremities

Differential Diagnosis

• Cardiovascular

  • HF (right-sided)

  • Pericardial effusion

  • Pericarditis

  • Tricuspid regurgitation

  • Tricuspid stenosis

  • Pulmonic stenosis

  • Cor pulmonale

  • Venous insufficiency (most common)

  • Venous obstruction

• Noncardiovascular

  • Cirrhosis

  • Low albumin (nephrotic syndrome, malnutrition, protein-losing enteropathy)

  • Cellulitis

  • Premenstrual fluid retention

  • Drugs (vasodilators, eg, calcium channel blockers; salt-retaining medications, eg, nonsteroidal anti-inflammatory drugs, thiazolidinediones)

  • Musculoskeletal (Baker cyst, gastrocnemius tear, compartment syndrome)

  • Lymphatic obstruction

  • Lymphedema (the Kaposi-Stemmer sign [the inability to pinch or pick up a fold of skin at the base of the second toe because of its thickness] can distinguish between lymphedema and chronic venous insufficiency)

  • Eclampsia

  • Hypothyroidism with myxedema

  • Filariasis

Laboratory Tests

• Serum creatinine, blood urea nitrogen

• D-dimers

• Urinalysis

• Liver chemistries: serum alkaline phosphatase, aspartate aminotransferase, gamma glutamyl-transpeptidase, total bilirubin, albumin

• Thyroid-stimulating hormone

Imaging Studies

• Duplex ultrasonography is diagnostic study of choice to detect chronic venous insufficiency due venous valve incompetence

• Ankle-brachial pressure index (ABPI)

• Lymphoscintigraphy can be used to confirm a clinical suspicion of lymphedema

Diagnostic Procedures

• Consider echocardiogram

• The "Wells prediction rule" allows a clinician to exclude a lower extremity DVT in patients without an ultrasound if the patient has low pretest probability for DVT and has a negative sensitive D-dimer test

• Treatment should be guided by underlying etiology

• Avoid diuretic therapy in patients with chronic venous insufficiency unless comorbid HF or other fluid-retaining condition

• Edema resulting from calcium channel blocker therapy responds to concomitant therapy with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers

• Mechanical measures effective in chronic venous insufficiency

  • Leg elevation, above the level of the heart, for 30 min three to four times daily and during sleep

  • Compression therapy with stockings and devices

    • To control simple edema, 20–30 mm Hg is usually sufficient

    • To control moderate to severe edema associated with ulcer formation, 30–40 mm Hg is usually required

  • Ambulatory exercise to increase venous return through calf muscle contractions

• Refrain from using compression therapy if there are risk factors for or signs of peripheral arterial occlusive disease

• Horse chestnut seed extract is equivalent to compression therapy for mild to moderate chronic venous insufficiency

• For lymphedema,

  • New bandaging systems applied twice weekly can be effective

  • Liposuction, suction-assisted lipectomy, and subcutaneous drainage may be beneficial if conservative measures fail

• Short-term manual lymphatic drainage treatment may improve chronic venous insufficiency severity, symptoms, and quality of life

• For patients with reduced mobility and leg edema, intermittent pneumatic compression treatment can reduce edema and improve ankle range of motion

• Balneotherapy

  • May result in a moderate improvement in pain, quality of life, and skin pigmentation changes

  • However, no clear effect on disease severity signs and symptoms score, adverse effects, leg ulcers, and edema

When to Refer

• Refer patients with chronic lower extremity ulcerations requiring specialist wound care

• Refer patients with nephrotic syndrome to a nephrologist

• Refer patients with coexisting severe arterial insufficiency (claudication) that would complicate treatment with compression stockings to a vascular surgeon

When to Admit

• Pending definitive diagnosis in patient at high risk for DVT despite normal lower extremity ultrasound

• Severe, acute swelling raising concern for an impending compartment syndrome

• Severe edema that impairs ability to ambulate or perform activities of daily living