Lower Extremity Edema – Causes, Treatment and Prevention
What is Edema
Lower extremity edema is a problem affecting approximately 20% of adults over age 50 (in industrialized nations). Edema, or swelling, is the result of increased pressure in the venous and/or lymphatic system that results in inadequate drainage from the legs. When this occurs, fluid builds up and leaks out into the interstitial space, resulting in the clinical finding of edema. Venous hypertension, also known as venous insufficiency, is a common cause of lower extremity edema. Long-Standing lower extremity swelling is often painful and can limit a patient’s mobility as well as increase the risk of secondary complications such as wounds.
Signs and Symptoms Of Lower Extremity Edema
Patients with lower extremity edema often complain of:
- Puffiness in the feet, ankles, or legs
- A feeling of leg heaviness or throbbing pain
- Snug clothing and/or jewelry
- Joint stiffness and feeling of skin tightness
- Swelling is often better right after getting up in the morning and worse over the course of the day (especially with standing).
On physical exams, these patients have enlarged girth of the affected extremity. Other findings include:
- Pitting edema, in which the tissue can be depressed with digital pressure, results in a depression that slowly dissipates.
- Skin discoloration is common
- Varicose veins may be present
- Patients may have shiny skin with hair loss
- In advanced stages, the skin may have an overall hyperkeratotic appearance (so-called “alligator skin”). Papules, plaques, and nodules may be present, resulting in a cobblestone-like appearance.
The edema is often worse when the legs are dependent, improving with elevation and compression.
Causes of Lower Extremity Edema
Acute onset unilateral edemaAcute onset unilateral edema results from a recent event such as a deep venous thrombosis (DVT), traumatic injury, infection, or mass/tumor.
Chronic unilateral edemaChronic unilateral edema may be caused by lymphatic abnormality/lymphedema, post-thrombotic syndrome, radiation changes, surgical scarring (following lymph node dissection), vascular malformation, and infection.
Acute onset bilateral edema
Acute onset bilateral edema causes include bilateral DVTs, acute heart failure, acute hepatic or renal
failure, and thrombosis of the inferior vena cava (IVC). Less common causes include IVC tumors, trauma, and
bilateral infections. Some medications may cause lower extremity edema, including some antihypertensives,
hormones, and chemotherapy.
Chronic bilateral edema
Chronic bilateral edema is the type most commonly seen in outpatient practice and tends to be the result of systemic causes. Common etiologies include venous insufficiency or reflux, pulmonary hypertension, chronic heart failure, chronic hepatic or renal failure, chronic IVC occlusion or compression, lymphedema, lipedema, pregnancy, obesity, hypoalbuminemia or malabsorption syndrome.
The most common cause of lower extremity edema in patients aged>50 is venous insufficiency. Also called venous hypertension, it results from the incompetence of the valves and venous reflux.
Workup and Evaluation of Lower Extremity Edema
Lower extremity duplex ultrasound is the initial test of choice when there is no clear cause of the edema. It can demonstrate venous anatomy, valve function, reflux, and potential thrombus with a sensitivity and specificity of >90%.
Ultrasound may also be used to evaluate the abdomen/pelvis for masses, lymph nodes, IVC thrombosis, and compression. CT or MRI should be used if there are significant concerns for intra abdominal or pelvic abnormalities.
Venography with intravascular ultrasound (IVUS) is an invasive procedure that allows for the assessment and treatment of venous pathology resulting from stenoses or lesions. Venography is typically only performed when other studies have been performed with inconclusive results.
If the evaluation of the lymphatic system is required, lymphoscintigraphy is the imaging of choice. Lymphangiography has been replaced by lymphoscintigraphy due to the technical difficulty and risk of complications associated with the invasive angiographic procedure.
Treatment of Lower Extremity Edema
Treatment selection depends on the underlying etiology of the edema. Assuming that underlying causes have been treated (DVT, cardiac/renal/hepatic failure, tumor, infection, trauma, etc), management of the edema itself is similar regardless of cause.
The mainstays of treatment are compression and elevation.
- Compression may be provided in a variety of ways. It is always important to note that arterial and/or cardiac disease may limit the amount of compression that is safe to apply. Assuming no contraindications exist, the amount of compression required depends on the degree of edema present. Compression of 15-20 mmHg is a good general guideline, although patients with minimal edema may do well with just 10-15 mmHg compression.
- Patients with severe edema require 20-40 mmHg compression. Compression bandages such as four-layer wraps, sequential compressive devices, and Unna boots may be indicated in these cases
- Patient compliance is important; it is far better to have less-than-ideal compression that the patient wears than ideal compression that the patient never uses. Most patients do not like wearing full-length compression stockings; knee-high compression socks tend to result in much better compliance. Arthritis and decreased grip strength can make it difficult for patients to put on their compression devices. Zipper or velcro-type wrap closure devices are often useful in these cases.
- The other hallmark of treatment is lower extremity elevation. In ideal circumstances, the patient should have their legs elevated to the level of their heart, as is the case when lying in bed. In the patient’s daily life, however, it is rare for patients to elevate their legs to that degree.
- Advising patients to keep their feet off the floor whenever possible is helpful. Regular use of a leg rest, reclining chair, or ottoman is beneficial. It is better to have some elevation than none at all.
- There are other treatments that may be of benefit, depending on the etiology of the edema.
- Diuretics may be beneficial to decrease intravascular volume and pressure.
- Endovenous laser ablation or radiofrequency ablation (RFA) is a minimally invasive procedure to close damaged veins. This may be beneficial in some cases.
- Sclerotherapy may be used to close damaged veins in more severe cases.
- Surgical ligation, or vein stripping, is typically only considered in severe cases. This involves tying off or removing the affected veins.
Prevention of Lower Extremity Edema
While most people do not have the underlying conditions that cause edema, it can be beneficial to ensure a good venous return to avoid potential problems. This can be important for people who stand for long periods of time, such as nurses or restaurant staff. Many of these people find that knee-high light compression socks can help prevent a feeling of heaviness and tiredness from prolonged standing. There is no data on the effectiveness of this for prevention, but it may be helpful.
Regular exercise is also important in minimizing edema. Even brief periods of walking can be beneficial to patients with edema.
Lower extremity edema is a common problem affecting millions of Americans. There is a multitude of possible causes for this, but the most common cause is venous insufficiency. In patients whose edema is caused by a correctible condition such as acute thrombus, mass, or infection, treatment of the underlying cause can correct the edema. Most patients with edema, however, must manage the condition long-term. Long-term management of edema involves the use of compression garments and elevation of the involved extremity
What is the best exercise for edema in the legs?
Walking is the best exercise to help reduce leg edema. Swimming, pool exercise, and biking are also very good to help with edema. There are also leg exercises specifically aimed at edema reduction, which may be of significant benefit when weight bearing is difficult.
How long does it take to get rid of edema in the legs?
This depends on how severe the edema is and what has caused it. Mild edema due to venous stasis can resolve in a few days with effective compression and leg elevation. Severe lymphedema may improve but never completely resolve. Most patients find that their edema improves a bit each day when they are able to use their compression, elevate their legs, and get a bit of exercise.
Will drinking more water help with edema?
To a degree, yes. When a person becomes dehydrated, the body takes this as a signal to hold onto fluid, which can worsen edema. Proper hydration helps the body maintain its normal water balance and allows interstitial fluid to drain out of the tissue. It is important not to over-hydrate if the edema is caused by organ disease (such as heart failure); patients should discuss this with their physician.
What happens if leg edema is left untreated?
Left untreated, most leg edema will continue to progress. Increased edema sets the stage for venous valve dysfunction, development or worsening of stasis, and development of lower extremity wounds. Patients can also see permanent skin thickening and other skin changes from untreated edema. Joint pain, leg heaviness, and general pain when walking tend to increase as edema worsens.
When should I be concerned about lower leg swelling?
Sudden leg swelling, especially painful swelling in just one leg, should prompt immediate medical evaluation. New onset leg swelling in general should be evaluated by the patient’s primary physician, to make sure the underlying cause is diagnosed and treated. Swelling associated with erythema, fever, pain (different from any baseline pain), systemic symptoms like shortness of breath, and new wounds should all require prompt medical evaluation.
Can dehydration cause edema in the legs?
Strange as it sounds, yes, dehydration can cause or exacerbate leg edema. Dehydration signals the body to retain fluid. It is important to hydrate appropriately and avoid things that may exacerbate fluid retention, such as caffeine and alcohol.
Do swollen legs mean heart problems?
Heart failure is one cause of swollen legs, but it is not the only cause. There are many causes of leg edema and many can be effectively treated. Medical evaluation is essential in treating and managing this problem.
Where does fluid go when the legs are elevated?
Excess fluid builds up in the interstitial space (spaces between the cells in the soft tissue). With elevation, the fluid migrates back into the lymphatic and venous system and re-enters the circulatory system.
Can coffee make your feet swell?
The caffeine in coffee may function as a diuretic and lead to dehydration-related swelling. Aside from dehydration, coffee itself does not cause edema.
What organ controls water retention?
Fluid balance in the body is impacted by several organ systems, but the kidneys control how much water is retained or expressed in the urine. The lymphatic system contributes to water balance in the body by collecting excess fluid and returning it to the venous system. The skin is a source of water loss through evaporation, even without sweating. Water is lost in exhaled air from the lungs. The hypothalamus in the brain secretes hormones that regulate blood osmolality and blood volume, ie, the amount of water present in the bloodstream.
What medications may increase lower extremity edema?
Many antihypertensives, hormones, and chemotherapy can cause leg edema. Common medications include calcium channel blockers, gabapentin, NSAIDs, oral contraceptives, corticosteroids, and some medications to treat Parkinson’s disease and diabetes.
What lack of vitamins causes edema?
Lack of Thiamine (vitamin B1) can cause peripheral edema. Deficiencies of magnesium, vitamin D, and vitamin B12 are all associated with edema.
How many hours a day should you wear compression socks?
The best plan is to put your compression socks on when you get out of bed and take them off when you get ready for bed at night. Unless advised otherwise by your physician, you should not wear compression socks overnight.
How do you drain edema fluid naturally?
The best way to drain edema is to wear compression socks and elevate the legs. Light exercise such as walking is very helpful in draining excess fluid from the legs.
Resources and References
- Peripheral edema: A common and persistent health problem for older Americans. Soroush Besharat, Hanna Grol-Prokopczyk, Shan Gao, Changyong Feng, Frank Akwaa, Jennifer S. Gewandter. Published: December 16, 2021 https://doi.org/10.1371/journal.pone.0260742
- Malgor RD, Labropoulos N. Diagnosis of venous disease with duplex ultrasound. Phlebology 2013; 1:158–161