Edema
Basics
Swelling caused by the build-up of excess fluids in the body is called edema. The swelling may be limited to specific areas like the ankles or legs, or it may be spread over large areas of the body.
Edema is classified primarily by the location of the swelling. For example, peripheral edema is swelling of the ankles, feet, and legs. Pulmonary edema is accumulation of fluid in the lungs. Periorbital edema is swelling around the eyes. Massive edema (also known as anasarca) is swelling covering a large part of the body. Other body locations that may become swollen include the gums, lymph glands, face, abdomen, breasts, scrotum (in men), or the joints.
Edema is a symptom associated with several different underlying diseases. Slight swelling is usually not a serious medical problem, but edema can be a long-term, progressive manifestation of disease with serious consequences such as leg ulcers.
Causes
A wide variety of medical conditions can cause edema, including kidney, liver, and heart disease.
Several of the body's organs and glands affect fluid balance. Diseases that affect these organs and prevent them from functioning normally can cause the kidneys to retain salt and water (two major components of edema fluid). This excess fluid then “leaks” out of the body's circulatory system and into surrounding tissues, causing them to swell.
Pulmonary edema can be a complication of heart failure.
Serious, inadequately treated heart failure can result in pulmonary edema. As the heart pumps less efficiently, fluid leaks out of the veins in the lungs and fills the air sacs, making it difficult to breathe. Pulmonary edema is life-threatening, and if left untreated, can rapidly become fatal. People with less severe heart failure that does not lead to pulmonary edema may also experience swelling in their ankles.
Edema may also be caused by chronic lung disease.
Severe chronic lung disease—such as chronic obstructive pulmonary disease (COPD), emphysema, or chronic bronchitis—may restrict blood flow through the vessels in the lungs. This restricted blood flow creates pressure in the vessels that can back up throughout the rest of the circulatory system. The pressure causes fluid to leak into surrounding tissues, causing swelling, such as in the legs and feet.
Varicose veins may cause peripheral edema.
Tiny valves in leg veins help the circulatory system move blood from the lower legs and feet back toward the heart. As people age, these valves often become weakened, resulting in blood pooling in the lower legs, forming varicose veins. The pressure from the pooling blood can cause fluid to leak into the surrounding tissue, causing swelling of the lower legs, ankles, or feet.
Sitting or standing too long may cause edema.
This type of edema is called orthostatic edema. It may be aggravated by hot weather, and can occur after long automobile or airplane trips, or any time a person stands or sits in one position for a long period of time.
Several different types of medications can cause edema.
These medications include oral contraceptives containing estrogen or progesterone, blood pressure medications, certain antidepressants, oral corticosteroids, and testosterone.
Swelling in the ankles and legs commonly occurs during the later stages of pregnancy.
As the uterus enlarges, it puts pressure on the vena cava, a large vessel that returns blood to the heart from the rest of the body. This pressure then backs up through the circulatory system, causing increased blood pressure in the legs, ankles, and feet. Ultimately, this pressure causes fluid to leak into the surrounding tissue.
Other causes of edema include allergic reactions, sunburns, malnutrition, injury or trauma, blockages in the lymphatic system (caused by infection, inflammation, or cancer), exposure to high altitude (rare), and hormonal changes associated with menstruation (in some women). Nephrotic syndrome, in which damaged kidneys loose excess protein in the urine, can lead to severe swelling in the ankles. Severe liver disease can lead to cirrhosis and excess ankle swelling.
Symptoms
The symptoms of edema vary depending on the location and the extent of swelling.
For most types of edema, fluid builds up under the skin, causing swelling and making the overlying area stretched and shiny. Edema may be pitting or non-pitting. With pitting edema, pressing a finger against a swollen area and then removing it leaves an indentation that slowly disappears. When edema becomes more severe, the tissue swells so much that it can’t be displaced, and no indentation is left in the skin after applying pressure. This type of edema is called non-pitting. Edema that occurs over pressure points over bony areas of the body can develop into serious sores or ulcers, especially in bedridden patients.
Peripheral edema causes swelling of the ankles, feet, or legs.
This type of edema is very common, especially among older adults. It is often painless, and may affect both legs. Because of gravity, the swelling is usually most severe in the lower legs, but the upper calves and thighs can be affected as well.
Pulmonary edema is a medical emergency characterized by severe difficulty breathing.
Symptoms of pulmonary edema include:
If you experience any of these symptoms, seek immediate medical attention.
Risk Factors
Usually, edema is a symptom of another underlying condition. In such cases, the risk factors for edema are the same as those for the underlying condition.
In other words, when edema is associated with serious conditions such as kidney, liver, heart, and lung disease, the risk factors for edema are the same as those for the underlying diseases. For example, smoking is a major risk factor for chronic lung disease, high blood pressure is a major risk factor for heart disease, and obesity is a major risk factor for both heart disease and diabetes. All of these risk factors, then, also increase a person’s risk of developing edema.
Edema becomes more common with age.
Because many of the underlying causes of edema occur more frequently with age, edema itself also becomes more common as people get older.
Diagnosis
Swelling caused by the build-up of excess fluids in the body is called edema. The swelling may be limited to specific areas like the ankles or legs, or it may be spread over large areas of the body.
Edema is classified primarily by the location of the swelling. For example, peripheral edema is swelling of the ankles, feet, and legs. Pulmonary edema is accumulation of fluid in the lungs. Periorbital edema is swelling around the eyes. Massive edema (also known as anasarca) is swelling covering a large part of the body. Other body locations that may become swollen include the gums, lymph glands, face, abdomen, breasts, scrotum (in men), or the joints.
Edema is a symptom associated with several different underlying diseases. Slight swelling is usually not a serious medical problem, but edema can be a long-term, progressive manifestation of disease with serious consequences such as leg ulcers.
A wide variety of medical conditions can cause edema, including kidney, liver, and heart disease.
Several of the body's organs and glands affect fluid balance. Diseases that affect these organs and prevent them from functioning normally can cause the kidneys to retain salt and water (two major components of edema fluid). This excess fluid then “leaks” out of the body's circulatory system and into surrounding tissues, causing them to swell.
Pulmonary edema can be a complication of heart failure.
Serious, inadequately treated heart failure can result in pulmonary edema. As the heart pumps less efficiently, fluid leaks out of the veins in the lungs and fills the air sacs, making it difficult to breathe. Pulmonary edema is life-threatening, and if left untreated, can rapidly become fatal. People with less severe heart failure that does not lead to pulmonary edema may also experience swelling in their ankles.
Edema may also be caused by chronic lung disease.
Severe chronic lung disease—such as chronic obstructive pulmonary disease (COPD), emphysema, or chronic bronchitis—may restrict blood flow through the vessels in the lungs. This restricted blood flow creates pressure in the vessels that can back up throughout the rest of the circulatory system. The pressure causes fluid to leak into surrounding tissues, causing swelling, such as in the legs and feet.
Varicose veins may cause peripheral edema.
Tiny valves in leg veins help the circulatory system move blood from the lower legs and feet back toward the heart. As people age, these valves often become weakened, resulting in blood pooling in the lower legs, forming varicose veins. The pressure from the pooling blood can cause fluid to leak into the surrounding tissue, causing swelling of the lower legs, ankles, or feet.
Sitting or standing too long may cause edema.
This type of edema is called orthostatic edema. It may be aggravated by hot weather, and can occur after long automobile or airplane trips, or any time a person stands or sits in one position for a long period of time.
Several different types of medications can cause edema.
These medications include oral contraceptives containing estrogen or progesterone, blood pressure medications, certain antidepressants, oral corticosteroids, and testosterone.
Swelling in the ankles and legs commonly occurs during the later stages of pregnancy.
As the uterus enlarges, it puts pressure on the vena cava, a large vessel that returns blood to the heart from the rest of the body. This pressure then backs up through the circulatory system, causing increased blood pressure in the legs, ankles, and feet. Ultimately, this pressure causes fluid to leak into the surrounding tissue.
Other causes of edema include allergic reactions, sunburns, malnutrition, injury or trauma, blockages in the lymphatic system (caused by infection, inflammation, or cancer), exposure to high altitude (rare), and hormonal changes associated with menstruation (in some women). Nephrotic syndrome, in which damaged kidneys loose excess protein in the urine, can lead to severe swelling in the ankles. Severe liver disease can lead to cirrhosis and excess ankle swelling.
The symptoms of edema vary depending on the location and the extent of swelling.
For most types of edema, fluid builds up under the skin, causing swelling and making the overlying area stretched and shiny. Edema may be pitting or non-pitting. With pitting edema, pressing a finger against a swollen area and then removing it leaves an indentation that slowly disappears. When edema becomes more severe, the tissue swells so much that it can’t be displaced, and no indentation is left in the skin after applying pressure. This type of edema is called non-pitting. Edema that occurs over pressure points over bony areas of the body can develop into serious sores or ulcers, especially in bedridden patients.
Peripheral edema causes swelling of the ankles, feet, or legs.
This type of edema is very common, especially among older adults. It is often painless, and may affect both legs. Because of gravity, the swelling is usually most severe in the lower legs, but the upper calves and thighs can be affected as well.
Pulmonary edema is a medical emergency characterized by severe difficulty breathing.
Symptoms of pulmonary edema include:
If you experience any of these symptoms, seek immediate medical attention.
Usually, edema is a symptom of another underlying condition. In such cases, the risk factors for edema are the same as those for the underlying condition.
In other words, when edema is associated with serious conditions such as kidney, liver, heart, and lung disease, the risk factors for edema are the same as those for the underlying diseases. For example, smoking is a major risk factor for chronic lung disease, high blood pressure is a major risk factor for heart disease, and obesity is a major risk factor for both heart disease and diabetes. All of these risk factors, then, also increase a person’s risk of developing edema.
Edema becomes more common with age.
Because many of the underlying causes of edema occur more frequently with age, edema itself also becomes more common as people get older.
Diagnosing the underlying cause is essential for treating edema effectively. When you seek treatment for unexplained edema, your physician will start by taking a medical history.
The questions will focus on the timing, location, severity, and duration of your symptoms. Your physician will also ask questions to determine whether you have had any other signs or symptoms of kidney, liver, thyroid, lung, or heart disease that may help in diagnosing the underlying cause of your swelling.
Your doctor will then perform a physical examination.
The examination is likely to be extensive, and will include listening to your heart and lungs, examining your skin and nails, testing your skin tone and its response to pressure, and looking at the whites of your eyes. The purpose of the exam is to determine whether you display any signs or symptoms of heart, lung, liver, or kidney disease that may be causing your edema.
Blood and urine tests will help your physician determine whether or not you have liver or kidney disease.
When the kidneys are damaged, they excrete excessive amounts of protein into the urine. A urine test can detect any excess protein. Similarly, reduced blood levels of the protein albumin may indicate serious kidney disease. Blood tests can also be used to test for liver disease, heart disease, and thyroid disease that may be contributing to your edema.
Your physician may order an x-ray of your lungs to test for lung disease or pulmonary edema.
Tissue damage caused by chronic lung diseases such as COPD, emphysema, or chronic bronchitis is usually visible on a chest x-ray. In addition, the x-ray can also determine whether fluid is building up in the air sacs of your lungs, resulting in pulmonary edema.
In cases where heart disease is a suspected cause of the edema, your physician may order cardiac tests.
Prevention and Screening
Treatment
Pulmonary edema is a life-threatening medical emergency requiring hospitalization and immediate treatment.
Seek immediate medical treatment if you experience any of the following symptoms:
Treatment for pulmonary edema may include oxygen, being put on a ventilator, and medications that remove fluid from the body (diuretics) or improve heart function (vasodilators). Other medications may be used as well to treat the underlying heart disease. Tranquilizers or other anti-anxiety drugs may help with the fear and panic that may accompany a person's inability to breathe.
People who have swelling and pain in only one calf or ankle, especially if it is sudden in onset, may have a blood clot in that leg. A blood clot in the leg can go to the lungs, and this is a medical emergency. Anyone concerned about a blood clot in the leg should seek immediate care from a doctor.
Mild peripheral edema can often be minimized or prevented by elevating the affected limbs and using support garments.
Mild swelling caused by varicose veins or pregnancy can be reduced using simple techniques. Elastic bandages or support stockings can reduce fluid accumulation in the ankles or lower legs. Support gloves can help prevent fluid from pooling in the hands or wrists in the infrequent cases where edema occurs in the upper extremities. Elevating the legs or arms while lying down can also help prevent fluid from pooling in the extremities.
Your physician may recommend dietary changes to prevent edema.
Your physician may recommend a lower sodium diet, as salt intake can contribute to edema. In some cases, reducing your fluid intake may be helpful as well. As always, a healthy diet including fruits and vegetables provides the nutrients necessary to keep the skin and other body tissues in good condition.
Regular exercise can help reduce or prevent swelling in the legs and ankles.
Walking, in particular, helps veins in the legs move blood back to the heart.
Swollen tissues over bony areas become fragile over time. For chronic edema, take care to prevent the skin from breaking down.
Take steps to prevent any possible underlying disease.
Because edema is usually a symptom of another underlying condition, taking steps to prevent the condition will also help prevent the edema. For example, stopping smoking will reduce your risk of developing chronic lung disease, a major cause of edema. Similarly, losing weight may reduce your risk of developing diabetes or serious heart disease, and treating alcohol or drug abuse may reduce your risk of chronic liver disease.
Your doctor is the best source of information on the drug treatment choices available to you.
In some cases, surgery may be necessary to treat varicose veins. Once the veins are removed, less blood should pool in the lower legs, reducing any swelling.
The prognosis for edema depends on the underlying cause.
The prognosis for most cases of edema is good. Simple measures such as dietary changes and elevating the affected limb can reduce or prevent swelling. Even pulmonary edema can be cured with immediate treatment and control of the underlying cause.
The prognosis for edema associated with serious underlying conditions, however, depends on the condition. For example, pulmonary edema can be fatal when it is caused by heart disease.
Follow-up depends on the underlying cause of the edema.
For mild edema without a serious underlying cause, follow-up may not be required unless unexplained edema recurs. For more serious cases, follow-up physician visits may be required to monitor fluid and electrolyte balances in the body. Serious heart, lung, liver, or kidney disease may require frequent follow-up and ongoing treatment.