Understand the venous drainage of the foot.
Understand the venous drainage of the lower limb
Is any venous reflux normal?
No. Lower extremity veins normally have unidirectional flow cephalad. One-way valves are more numerous distally.
What does venous capacitance allow for? How does this differ from arteries?
Venous capacitance allows for a significant amount of blood pooling in the venous system, which differs from arteries that have muscular walls.
Describe the physiologic function of the calf-muscle pump mechanism.
The calf-muscle pump is the principal force to return blood to the heart by displacing venous blood in vertical and horizontal directions and generating an ambulatory pressure gradient between the thigh and lower leg veins and bidirectional streaming within calf perforators.
Identify causes of unilateral lower extremity swelling, which are acute in nature (< 72 hours).
This should include deep vein thrombosis (DVT), popliteal cyst, rupture of calf muscle involving the head of the gastrocnemius, bacterial cellulitis, and erythema nodosum.
Identify causes of unilateral swelling that is chronic (≥ 72 hours).
lymphedema, chronic venous insufficiency, reflex sympathetic dystrophy, congenital venous malformations, and malignancy
Identify causes of peripheral edema including systemic causes of increased fluid pressure
Congestive heart failure, restrictive cardiac disease, and constrictive pericarditis.
Other examples include excessive fluid administration, iliac compression syndrome, venous thrombosis, venous valvular incompetence, external compression, injury, compartment syndrome, or reflex sympathetic dystrophy.
Identify etiologies of peripheral edema caused by decreased oncotic pressure.
Decreased albumin synthesis as seen in protein-calorie malnutrition, or increased albumin loss due to malabsorption, cirrhosis, renal disease, hypoproteinemia syndromes, Cushing's disease or syndrome, and preeclampsia.
Identify causes of peripheral edema related to altered permeability
Histamine release (hives); loss of arteriolar muscle tone (angioedema); vasculitis (erythema nodosum); serum sickness; lymphatic obstruction, hypothyroidism, malignancy, especially prostatic cancer and lymphoma, congenital, and familial causes (Milroy disease).
Identify causes of upper extremity edema
Superior vena cava syndrome as seen with lung cancer, thyroid cancer, thymus cancer, neurofibromatosis, idiopathic mediastinal fibrosis, histoplasmosis, sarcoidosis, multinodular goiter, and pleural calcifications.
What physical exam changes does venous disease create?
Changes in venous disease include reticular veins, varicose veins, edema, atrophie blanche, venous eczema, hemosiderin deposition and/or ulceration.
What physical changes can lymphedema create in the extremity?
Lymphedema can be unilateral or bilateral, and progressive stages can include papillomatosis and hyperkeratosis of the skin. Advanced stages include elephantiasis.
What are the causes of unilateral swelling in the extremity?
Causes of unilateral swelling include venous disease, deep vein thrombosis, trauma, and lymphedema.
What are the causes of bilateral swelling?
Causes of bilateral swelling are usually systemic and include congestive cardiac failure and inferior vena cava stenosis/obstruction.
What is the mainstay of lower extremity vascular imaging?
Ultrasound imaging is the mainstay of lower extremity vascular testing.
A 27-year-old woman presents to the emergency room with a tender swollen left leg. What is your approach to this patient?
- Search for risk factors: oral contraceptive use, smoking status, family history, and trauma. Do thorough H&P.
- Get venous ultrasound.
- If DVT is identified, the mainstay of treatment is anticoagulation, leg elevation, and compression therapy.
A 55-year-old man presents to his primary care physician complaining of swelling in both legs. He denies any trauma but has some dyspnea on exertion. He has been unable to wear compression stockings. What is your management plan?
Recognize that the patient has bilateral lower extremity swelling, and that this is likely from a systemic cause.
Understand that the patient should have a workup for cardiovascular and renal disease.
A 48-year-old woman with a history of DVT 20 years previous presents with worsening unilateral swelling of her left leg. A repeat ultrasound is negative for acute DVT; however, she has significant venous reflux of. How would you manage this patient?