Edema

Definition

Edema is a condition of abnormally large fluid volume in the circulatory system or in tissues between the body's cells (interstitial spaces).

Description

Normally the body maintains a balance of fluid in tissues by ensuring that the same of amount of water entering the body also leaves it. The circulatory system transports fluid within the body via its network of blood vessels. The fluid, which contains oxygen and nutrients needed by the cells, moves from the walls of the blood vessels into the body's tissues. After its nutrients are used up, fluid moves back into the blood vessels and returns to the heart. The lymphatic system (a network of channels in the body that carry lymph, a colorless fluid containing white blood cells to fight infection) also absorbs and transports this fluid. In edema, either too much fluid moves from the blood vessels into the tissues, or not enough fluid moves from the tissues back into the blood vessels. This fluid imbalance can cause mild to severe swelling in one or more parts of the body.

Causes and symptoms

Many ordinary factors can upset the balance of fluid in the body to cause edema, including:

• Immobility. The leg muscles normally contract and compress blood vessels to promote blood flow with walking or running. When these muscles are not used, blood can collect in the veins, making it difficult for fluid to move from tissues back into the vessels.
• Heat. Warm temperatures cause the blood vessels to expand, making it easier for fluid to cross into surrounding tissues. High humidity also aggravates this situation.
• Medications. Certain drugs, such as steroids, hormone replacements, nonsteroidal anti-inflammatory drugs (NSAIDs), and some blood pressure medications may affect how fast fluid leaves blood vessels.
• Intake of salty foods. The body needs a constant concentration of salt in its tissues. When excess salt is taken in, the body dilutes it by retaining fluid.
• Menstruation and pregnancy. The changing levels of hormones affect the rate at which fluid enters and leaves the tissues.

Some medical conditions may also cause edema, including:

• Heart failure. When the heart is unable to maintain adequate blood flow throughout the circulatory system, the excess fluid pressure within the blood vessels can cause shifts into the interstitial spaces. Left-sided heart failure can cause pulmonary edema, as fluid shifts into the lungs. The patient may develop rapid, shallow respirations, shortness of breath, and a cough. Right-sided heart failure can cause pitting edema, a swelling in the tissue under the skin of the lower legs and feet. Pressing this tissue with a finger tip leads to a noticeable momentary indentation.
• Kidney disease. The decrease in sodium and water excretion can result in fluid retention and overload.
• Thyroid or liver disease. These conditions can change the concentration of protein in the blood, affecting fluid movement in and out of the tissues. In advanced liver disease, the liver is enlarged and fluid may build-up in the abdomen.
• Malnutrition. Protein levels are decreased in the blood, and in an effort to maintain a balance of concentrations, fluid shifts out of the vessels and causes edema in tissue spaces.

Some conditions that may cause swelling in just one leg include:

• Blood clots. Clots can cause pooling of fluid and may be accompanied by discoloration and pain. In some instances, clots may cause no pain.
• Weakened veins. Varicose veins, or veins whose walls or valves are weak, can allow blood to pool in the legs. This is a common condition.
• Infection and inflammation. Infection in leg tissues can cause inflammation and increasing blood flow to the area. Inflammatory diseases, such as gout or arthritis, can also result in swelling.
• Lymphedema. Blocked lymph channels may be caused by infection, scar tissue, or hereditary conditions. Lymph that can't drain properly results in edema. Lymphedema may also occur after cancer treatments, when the lymph system is impaired by surgery, radiation, or chemotherapy.
• Tumor. Abnormal masses can compress leg vessels and lymph channels, affecting the rate of fluid movement.

Symptoms vary depending on the cause of edema. In general, weight gain, puffy eyelids, and swelling of the legs may occur as a result of excess fluid volume. Pulse rate and blood pressure may be elevated. Hand and neck veins may be observed as fuller.

Diagnosis

Edema is a sign of an underlying problem, rather than a disease unto itself. A diagnostic explanation should be sought. Patient history and presenting symptoms, along with laboratory blood studies, if indicated, assist the health professional in determining the cause of the edema.

Treatment

Treatment of edema is based on the cause. Simple steps to lessen fluid build-up may include:

• Reducing sodium intake. A high sodium level causes or aggravates fluid retention.
• Maintaining proper weight. Being overweight slows body fluid circulation and puts extra pressure on the veins.
• Exercise. Regular exercise stimulates circulation.
• Elevation of the legs. Placing the legs at least 12 in (30.5 cm) above the level of the heart for 10-15 minutes, three to four times a day, stimulates excess fluid re-entry into the circulatory system.
• Use of support stocking. Elastic stockings, available at most medical supply or drug stores, will compress the leg vessels, promoting circulation and decreasing pooling of fluid due to gravity.
• Massage. Massaging the body part can help to stimulate the release of excess fluids, but should be avoided if the patient has blood clots in the veins.
• Travel breaks. Sitting for long periods will increase swelling in the feet and ankles. Standing and/or walking at least every hour or two will help stimulate blood flow.

The three "Ds"—diuretics, digitalis, and diet-are frequently prescribed for medical conditions that result in excess fluid volume. Diuretics are medications that promote urination of sodium and water. Digoxin is a digitalis preparation that is sometimes needed to decrease heart rate and increase the strength of the heart's contractions. Dietary recommendations include less sodium in order to decrease fluid retention. Consideration of adequate protein intake is also made.

For patients with lymphedema, a combination of therapies may prove effective. Combined decongestive therapy includes the use of manual lymph drainage (MLD), compression bandaging, garments and pumps, and physical therapy. MLD involves the use of light massage of the subcutaneous tissue where the lymph vessels predominate. Massage begins in an area of the body trunk where there is normal lymph function and proceeds to areas of lymphatic insufficiency, in an effort to stimulate new drainage tract development. (MLD should not be used for patients with active cancer, deep vein clots, congestive heart failure, or cellulitis.) MLD sessions are followed by application of compression garments or pumps. Physical therapy is aimed at strengthening the affected limb and increasing joint mobility.

Alternative treatment

Dietary changes, in addition to cutting back the amount of sodium eaten, may also help reduce edema. Foods that worsen edema, such as alcohol, caffeine, sugar, dairy products, soy sauce, animal protein, chocolate, olives, and pickles, should be avoided. Diuretic herbs can also help relieve edema. One of the best herbs for this purpose is dandelion (Taraxacum mongolicum ), since, in addition to its diuretic action, it is a rich source of potassium. (Diuretics flush potassium from the body and it must be replaced to avoid potassium deficiency.) Hydrotherapy using daily contrast applications of hot and cold (either compresses or immersion) may also be helpful.

KEY TERMS

Digitalis— A naturally occuring compound used in the preparation of the medication, digoxin, prescribed to increase the heart rate and strengthen the force of the heart's contractions.

Diuretics— Medications used in the treatment of fluid overload, to promote excretion of sodium and water.

Interstitial spaces— Areas of the body occuring outside the vessels or organs, between the cells.

Pitting edema— A swelling in the tissue under the skin, resulting from fluid accumulation, that is measured by the depth of indentation made by finger pressure over a boney prominence.

Resources

ORGANIZATIONS

Lymphedema and Wound Care Clinic of Austin. 5750 Balcones Dr., Ste. 110, Austin, TX 78731. (512) 453-1930.

Edema

Definition

Edema is a condition of abnormally large fluid volume in the circulatory system or in tissues between the body's cells (interstitial spaces).

Description

Normally the body maintains a balance of fluid in tissues by ensuring that the same amount of water entering the body also leaves it. The circulatory system transports fluid within the body via its network of blood vessels. The fluid, which contains oxygen and nutrients needed by the cells, moves from the walls of the blood vessels into the body's tissues. After its nutrients are used up, fluid moves back into the blood vessels and returns to the heart. The lymphatic system (a network of channels in the body that carry lymph, a colorless fluid containing white blood cells to fight infection) also absorbs and transports this fluid. In edema, either too much fluid moves from the blood vessels into the tissues, or not enough fluid moves from the tissues back into the blood vessels. This fluid imbalance can cause mild to severe swelling in one or more parts of the body.

Causes & symptoms

Many ordinary factors can upset the balance of fluid in the body to cause edema, including:

• Immobility. The leg muscles normally contract and compress blood vessels to promote blood flow with walking or running. When these muscles are not used, blood can collect in the veins, making it difficult for fluid to move from tissues back into the vessels.
• Heat. Warm temperatures cause the blood vessels to expand, making it easier for fluid to cross into surrounding tissues. High humidity also aggravates this situation.
• Medications. Certain drugs, such as steroids, hormone replacements, nonsteroidal anti-inflammatory drugs (NSAIDs), and some blood pressure medications may affect how fast fluid leaves blood vessels.
• Intake of salty foods. The body needs a constant concentration of salt in its tissues. When excess salt is taken in, the body dilutes it by retaining fluid.
• Menstruation and pregnancy . The changing levels of hormones affect the rate at which fluid enters and leaves the tissues.

Some medical conditions may also cause edema, including:

• Heart failure. When the heart is unable to maintain adequate blood flow throughout the circulatory system, the excess fluid pressure within the blood vessels can cause shifts into the interstitial spaces. Left-sided heart failure can cause pulmonary edema, as fluid shifts into the lungs. The patient may develop rapid, shallow respirations, shortness of breath, and a cough . Right-sided heart failure can cause pitting edema, a swelling in the tissue under the skin of the lower legs and feet. Pressing this tissue with a finger tip leads to a noticeable momentary indentation.
• Kidney disease. The decrease in sodium and water excretion can result in fluid retention and overload.
• Thyroid or liver disease. These conditions can change the concentration of protein in the blood, affecting fluid movement in and out of the tissues. In advanced liver disease, the liver is enlarged and fluid may build up in the abdomen.
• Malnutrition. Protein levels are decreased in the blood, and in an effort to maintain a balance of concentrations, fluid shifts out of the vessels and causes edema in tissue spaces.

Some conditions that may cause swelling in just one leg include:

• Blood clots. Clots can cause pooling of fluid and may be accompanied by discoloration and pain . In some instances, clots may cause no pain.
• Weakened veins. Varicose veins , or veins whose walls or valves are weak, can allow blood to pool in the legs. This is a common condition.
• Infection and inflammation. Infection in leg tissues can cause inflammation and increasing blood flow to the area. Inflammatory diseases, such as gout or arthritis, can also result in swelling.
• Lymphedema. Blocked lymph channels may be caused by infection, scar tissue, or hereditary conditions. Lymph that can't drain properly results in edema. Lymphedema may also occur after cancer treatments, when the lymph system is impaired by surgery, radiation, or chemotherapy.
• Tumor. Abnormal masses can compress leg vessels and lymph channels, affecting the rate of fluid movement.

Symptoms vary depending on the cause of edema. In general, weight gain, puffy eyelids, and swelling of the legs may occur as a result of excess fluid volume. Pulse rate and blood pressure may be elevated. Hand and neck veins may be observed as fuller.

Diagnosis

Edema is a sign of an underlying problem, rather than a disease unto itself. A diagnostic explanation should be sought. Patient history and presenting symptoms, along with laboratory blood studies, if indicated, assist the health professional in determining the cause of the edema.

Treatment

Simple steps to lessen fluid build-up may include:

• reducing sodium intake
• maintaining proper weight
• exercise
• elevation of the legs
• use of support stockings
• massage
• travel breaks

Nutritional therapy

A naturopath or a nutritionist may recommend the following dietary changes:

• Reduction of salt intake, including salty foods such as olives, soy sauce, or pickles. Cutting back the amount of sodium eaten may help reduce edema.
• Limited use of alcohol, caffeine , sugar, and dairy products.
• Increased consumption of whole grain foods, cucumbers, apples, potatoes, grapes, onions, cabbage, and oranges.
• Daily vitamin and mineral supplements.

Herbal therapy

Diuretic herbs can also help relieve edema. One of the best herbs for this purpose is dandelion (Taraxacum mongolicum ), since, in addition to its diuretic action, it is a rich source of potassium . (Diuretics flush potassium from the body, and it must be replaced to avoid potassium deficiency.)

Hydrotherapy

Hydrotherapy using daily contrast applications of hot and cold (either compresses or immersion) may also be helpful.

Other alternative treatments

Other alternative therapies may also reduce edema. They include traditional Chinese medicine , Ayurveda, juice therapy, and bodywork. Traditional Chinese medicine and acupuncture have an elaborate diagnostic system to determine the pattern causing the edema. Thus treatment, if done correctly, results not only in the removal of fluid, but also with the correction of the problem.

Allopathic treatment

The three "Ds"—diuretics, digitalis, and diet—are frequently prescribed for medical conditions that result in excess fluid volume. Diuretics are medications that promote urination of sodium and water. Digoxin is a digitalis preparation that is sometimes needed to decrease heart rate and increase the strength of the heart's contractions. One dietary recommendation includes less sodium in order to decrease fluid retention. Consideration of adequate protein intake is also made.

For patients with lymphedema, a combination of therapies may prove effective. Combined decongestive therapy includes the use of manual lymph drainage (MLD), compression bandaging, garments and pumps, and physical therapy.

Resources

BOOKS

The Burton Goldberg Group. "Edema." in Alternative Medicine: The Definitive Guide. Tiburon, CA: Future Medicine Publishing, Inc., 1999.

Monahan, Frances D., and Marianne Neighbors. Medical-Surgical Nursing: Foundation for Clinical Practice, 2nd ed. Philadelphia: W. B. Saunders, 1998.

ORGANIZATIONS

Lymphedema and Wound Care Clinic of Austin. 5750 Balcones Dr., Ste. 110, Austin, TX 78731. (512) 453-1930. <www.lymphedema.com>.

Mai Tran

Edema

Definition

Edema is the medical term for swelling. It is an abnormal retention of fluid in body tissue.

Description

Edema that is visible and localized often accompanies a soft-tissue injury, a sprain, or a fracture. However, it is also a component of generalized retention of fluid such as occurs in congestive heart failure (CHF). By weight, 60% of the human body is composed of water. In a remarkable process that is, under normal circumstances, a nearly perfect balance, water is exchanged between the blood and the tissues. As it circulates blood through the body, the pressure from the heart presses water out of capillaries and into body tissues. Osmotic (water-drawing) properties of certain blood proteins cause this process to reverse and fluid to be reabsorbed from the tissues back into the capillaries. To maintain equilibrium, the kidneys draw off excess fluid and salt, which are then excreted as part of the urine. When fluid is not released from the tissues, the result is edema.

Causes and symptoms

The causes and severity of edema cover a wide spectrum, including:

• mild edema that accompanies female hormone imbalance during the menstrual cycle
• allergies in which the chemical histamine is released by the immune system , resulting in fluid leaking into the tissues, which creates swelling
• injuries that do damage to capillaries, causing fluids to seep out into the tissue and not be reabsorbed by the damaged capillaries
• hormonal imbalance caused by taking certain hormonal medications such as corticosteroids , high estrogen contraceptives, or androgens (male hormones)
• beriberi (vitamin B₁ deficiency) and dietary protein deficiency, often found with malnutrition
• the venous congestion that accompanies cirrhosis of the liver and eventually decreases osmotic pressure
• kidney failure, which eventually allows salts and water to be retained in the tissues rather than being excreted
• nephritic syndrome, a condition in which large amounts of blood protein are lost and the blood loses its ability to draw fluid back out of the tissues
• congestive heart failure, a common condition, especially in the elderly, in which the heart functions less efficiently due to coronary artery disease , high blood pressure , or congenital or disease-caused abnormality in the heart

Other than traumatic injuries or allergic reactions, swelling typically develops quite slowly and often goes unnoticed at its onset. It is estimated that fluid in the body can increase by 15% without being visible. Frequently it is manifested at that point only by an increase in weight. When edema does become apparent, it is usually found in the lower part of the body, in the feet, ankles, legs, and lower back. A finger pressed into edematous skin will leave an imprint that slowly disappears as the fluid again refills that tissue.

Severe edematous conditions can cause fluid to gather in body cavities. Ascites, common with cirrhosis of the liver, is characterized by large amounts of fluid amassing in the peritoneal cavity of the abdomen. When liquid fills the pleural cavity adjacent to the lungs , it is termed pleural effusion; the liquid presses upon the lungs, causing difficulty in breathing. Pulmonary edema, which occurs when air sacs in the lungs become waterlogged, also causes respiratory complications.

Diagnosis

Diagnosis of the cause of edema is based upon physical examination and laboratory testing, plus a complete medical history. For patients with a history of CHF or

kidney disease, weights are frequently taken to watch for fluid retention.

Treatment

The simple act of elevating the legs sometimes will reduce edema. However, the primary means of treating edema is in determining the cause of the fluid retention and attempting to remedy that. Giving antihypertensive drugs to people with high blood pressure will sometimes eliminate the edema. Often, though, the underlying cause of the edema is not easily remedied, such as in the case of CHF. Treatment of CHF may include:

• limiting the salt in the diet
• taking diuretics, medications that stimulate the kidneys to excrete the excess salt and water
• taking angiotensin-converting enzyme inhibitors (ACE inhibitors) and vasodilator drugs, which cause blood vessels to expand and allow blood to flow easier, decreasing the work required of the heart
• taking beta blockers, which improve the functioning of the left ventricle of the heart
• taking digitalis, a drug that expands the ability of the heart to pump blood through the body
• having surgery to replace abnormal heart valves; in extreme cases, heart transplant may be needed

Prognosis

The outcome for edema depends heavily upon its cause. The best outlook for the relief of edema is when the underlying condition is treatable.

Health care team roles

Edema is most often noticed by either the patient, by a primary care physician or nurse-practitioner during a routine examination, or by nursing staff caring for the patient in a health care facility or at home.

Both registered nurses (RNs) and licensed practical nurses (LPNs) must complete a prescribed course in nursing and pass a state examination. RNs typically have a degree in nursing. Good nursing care of the patient with edema will include observation, elevating the legs if the

KEY TERMS

Capillaries —The term for any of the vessels that carry blood between the smallest arteries, or arterioles, and the smallest veins, venules.

Congestive heart failure —A condition in which the heart cannot circulate enough blood to meet the needs of the body.

Corticosteroids —A group of medications that have similar properties to the corticosteroid hormones that the adrenal glands produce naturally.

Fracture —A partial break in a bone.

Histamine —A chemical present in cells that is released during an allergic reaction and that causes the symptoms of inflammation, including swelling.

Osmosis —The passage of a fluid such as water through a sieve-like tissue called a semipermeable membrane from a less concentrated, or weaker, solution to a more concentrated, or stronger one.

Soft-tissue injury —Damage to tissue that encloses bones or joints, such as muscles, tendons, or ligaments.

Sprain —The tearing or stretching of ligaments holding bone ends together in a joint, usually caused by sudden, violent pulling.

lower extremities are swollen, monitoring vital signs and weights, and providing education about the cause of the edema.

Clinical laboratory scientists have specialized train ing and must pass a state examination. They draw blood samples or do the necessary tests on fluids withdrawn from fluid-filled body cavities.

Radiologic technologists have specialized training and must pass a state examination. They take x rays and other tests to visualize and monitor the course of disease processes that contribute to the edema.

Prevention

Prevention of edema is dependent upon treatment of the basic reason for the edema. Losing weight, stopping smoking, and reducing stress can all aid in reducing blood pressure. Proper nutrition can help to maintain a healthy circulatory system.

Resources

BOOKS

Weir, E. K. and Reeves, S. L., editors. Pulmonary Edema (American Heart Association Monograph Series). Futura, 1998.

ORGANIZATIONS

American Heart Association. Congestive Heart Failure 2000. <http://americanheart.org/>.

Joan M. Schonbeck

Edema

Definition

Edema is the medical term for swelling. It is an abnormal retention of fluid in body tissue.

Description

Edema that is visible and localized often accompanies a soft-tissue injury, a sprain, or a fracture. However, it is also a component of generalized retention of fluid such as occurs in congestive heart failure (CHF). By weight, 60% of the human body is composed of water. In a remarkable process that is, under normal circumstances, a nearly perfect balance, water is exchanged between the blood and the tissues. As it circulates blood through the body, the pressure from the heart presses water out of capillaries and into body tissues. Osmotic (water-drawing) properties of certain blood proteins cause this process to reverse and fluid to be reabsorbed from the tissues back into the capillaries. To maintain equilibrium, the kidneys draw off excess fluid and salt, which are then excreted as part of the urine. When fluid is not released from the tissues, the result is edema.

Causes and symptoms

The causes and severity of edema cover a wide spectrum, including:

• mild edema that accompanies female hormone imbalance during the menstrual cycle
• allergies in which the chemical histamine is released by the immune system, resulting in fluid leaking into the tissues, which creates swelling
• injuries that do damage to capillaries, causing fluids to seep out into the tissue and not be reabsorbed by the damaged capillaries
• hormonal imbalance caused by taking certain hormonal medications such as corticosteroids, high estrogen contraceptives, or androgens (male hormones)
• beriberi (vitamin B₁ deficiency) and dietary protein deficiency, often found with malnutrition
• the venous congestion that accompanies cirrhosis of the liver and eventually decreases osmotic pressure
• kidney failure, which eventually allows salts and water to be retained in the tissues rather than being excreted
• nephritic syndrome, a condition in which large amounts of blood protein are lost and the blood loses its ability to draw fluid back out of the tissues
• congestive heart failure, a common condition, especially in the elderly, in which the heart functions less efficiently due to coronary artery disease, high blood pressure, or congenital or disease-caused abnormality in the heart

Other than traumatic injuries or allergic reactions, swelling typically develops quite slowly and often goes unnoticed at its onset. It is estimated that fluid in the body can increase by 15% without being visible. Frequently it is manifested at that point only by an increase in weight. When edema does become apparent, it is usually found in the lower part of the body, in the feet, ankles, legs, and lower back. A finger pressed into edematous skin will leave an imprint that slowly disappears as the fluid again refills that tissue.

Severe edematous conditions can cause fluid to gather in body cavities. Ascites, common with cirrhosis of the liver, is characterized by large amounts of fluid amassing in the peritoneal cavity of the abdomen. When liquid fills the pleural cavity adjacent to the lungs, it is termed pleural effusion; the liquid presses upon the lungs, causing difficulty in breathing. Pulmonary edema, which occurs when air sacs in the lungs become waterlogged, also causes respiratory complications.

Diagnosis

Diagnosis of the cause of edema is based upon physical examination and laboratory testing, plus a complete medical history. For patients with a history of CHF or kidney disease, weights are frequently taken to watch for fluid retention.

Treatment

The simple act of elevating the legs sometimes will reduce edema. However, the primary means of treating edema is in determining the cause of the fluid retention and attempting to remedy that. Giving antihypertensive drugs to people with high blood pressure will sometimes eliminate the edema. Often, though, the underlying cause of the edema is not easily remedied, such as in the case of CHF. Treatment of CHF may include:

• limiting the salt in the diet
• taking diuretics, medications that stimulate the kidneys to excrete the excess salt and water
• taking angiotensin-converting enzyme inhibitors (ACE inhibitors) and vasodilator drugs, which cause blood vessels to expand and allow blood to flow easier, decreasing the work required of the heart
• taking beta blockers, which improve the functioning of the left ventricle of the heart
• taking digitalis, a drug that expands the ability of the heart to pump blood through the body
• having surgery to replace abnormal heart valves; in extreme cases, heart transplant may be needed

Prognosis

The outcome for edema depends heavily upon its cause. The best outlook for the relief of edema is when the underlying condition is treatable.

Health care team roles

Edema is most often noticed by either the patient, by a primary care physician or nurse-practitioner during a routine examination, or by nursing staff caring for the patient in a health care facility or at home.

Both registered nurses (RNs) and licensed practical nurses (LPNs) must complete a prescribed course in nursing and pass a state examination. RNs typically have a degree in nursing. Good nursing care of the patient with edema will include observation, elevating the legs if the lower extremities are swollen, monitoring vital signs and weights, and providing education about the cause of the edema.

Clinical laboratory scientists have specialized training and must pass a state examination. They draw blood samples or do the necessary tests on fluids withdrawn from fluid-filled body cavities.

Radiologic technologists have specialized training and must pass a state examination. They take x rays and other tests to visualize and monitor the course of disease processes that contribute to the edema.

KEY TERMS

Capillaries— The term for any of the vessels that carry blood between the smallest arteries, or arterioles, and the smallest veins, venules.

Congestive heart failure— A condition in which the heart cannot circulate enough blood to meet the needs of the body.

Corticosteroids— A group of medications that have similar properties to the corticosteroid hormones that the adrenal glands produce naturally.

Fracture— A partial break in a bone.

Histamine— A chemical present in cells that is released during an allergic reaction and that causes the symptoms of inflammation, including swelling.

Osmosis— The passage of a fluid such as water through a sieve-like tissue called a semipermeable membrane from a less concentrated, or weaker, solution to a more concentrated, or stronger one.

Soft-tissue injury— Damage to tissue that encloses bones or joints, such as muscles, tendons, or ligaments.

Sprain— The tearing or stretching of ligaments holding bone ends together in a joint, usually caused by sudden, violent pulling.

Prevention

Prevention of edema is dependent upon treatment of the basic reason for the edema. Losing weight, stopping smoking, and reducing stress can all aid in reducing blood pressure. Proper nutrition can help to maintain a healthy circulatory system.

Resources

BOOKS

Weir, E. K. and Reeves, S. L., editors. Pulmonary Edema (American Heart Association Monograph Series). Futura, 1998.

ORGANIZATIONS

American Heart Association. Congestive Heart Failure 2000. 〈http://americanheart.org/〉.

Edema

Definition

Edema is a general term for excess fluid build-up in a specific area of the body, multiple areas of the body, or throughout the body (generalized edema or anasarca). Edema can be temporary or permanent depending on its cause.

Description

Edema occurs when there is an imbalance, specifically an excess, of body fluid moving between the blood vessels and body tissues. This excess fluid is retained in the tissues and results in swelling. Pulmonary edema is edema in the lungs, ascites is edema in the abdomen, and edema in the lower extremities is called peripheral edema or dependent edema. Temporary edema, e.g., swelling caused by pregnancy and inactivity, is not usually serious. More persistent and serious cases of edema are usually caused by heart failure, kidney failure, or liver disease. The underlying cause of edema is best determined by a physician.

Demographics

Anyone can have edema but it is more common in individuals who are severely ill.

Causes and symptoms

Certain conditions increase the risk of developing edema including abnormal blood flow in the lower extremities (venous insufficiency), immobility, heat, certain medications, salt intake, menstruation, pregnancy, heart failure, kidney disease, thyroid disease, liver disease, and malnutrition . Venous insufficiency affects the feet or ankles and may occur only on one side of the body. Being immobile causes blood to

collect in the veins so fluid has more difficulty moving from the tissues back into the circulatory system and edema results. Heat causes blood vessels to expand which makes it easier for fluid to move into surrounding tissues. Excess intake of salt causes retention of fluid. Certain drugs including steroids (drugs that reduce swelling or inflammation), hormones, nonsteroidal anti-inflammatory drugs (NSAIDs), and some high blood pressure medicines may contribute to the development of edema. Edema can be a side effect of some medications. Edema may occur as a result of premenstrual syndrome (PMS). Swelling of the hands, feet, and face are common in pregnancy due to increased retention of sodium and water and pressure from the uterus on the veins in the lower extremities. In congestive heart failure , because the heart muscle is weakened, its pumping action is decreased; therefore, fluid builds up in the lungs and other parts of the body. If there is right-sided heart failure, there is swelling in the legs and abdomen. In left-sided heart failure, there is pulmonary edema. Decreased excretion of sodium and fluid occurs in kidney disease causing fluid build-up. Thyroid disease, liver disease, and malnutrition affect movement of fluid in and out of tissues resulting in edema.

Symptoms of edema depend on its location and cause. Generally the area affected by edema will be stretched and have a shiny appearance. Edema may be pitting or non-pitting. In pitting edema, pushing on the swollen area with a finger for several seconds will leave an indention on the skin after the pressure is released. The level of indentation determines the degree of pitting edema. Non-pitting edema will not leave an indentation. Clothing and jewelry may feel tight and urine output may be decreased even with normal intake of fluids. In pulmonary edema, symptoms may include shortness of breath, difficulty breathing, and bluish color to the lips and fingernails. In ascites, the abdomen may be distended. Symptoms of peripheral edema include swelling in the lower legs, which worsens after sitting or standing for long periods of time.

Diagnosis

A physical examination including visual inspection of the skin and a medical history to determine duration, quality, and location of symptoms is vital. Blood tests, urine tests, x-ray and electrocardiogram (EKG) may be done to assist in determining the underlying cause(s) of edema.

Blood and urine tests may be ordered to evaluate kidney and liver function. An EKG may be done to detect abnormal heart functioning. A chest x-ray can assess for presence of fluid in the lungs and determine the size and shape of the heart.

Treatment

Treatment is aimed at correcting the underlying cause of edema. The physician may order fluid pills (diuretics ) to remove excess fluid. Pulmonary edema requires immediate medical attention since fluid in the lungs impairs oxygen transport from the lungs to the blood system. Edema associated with heart failure may require heart medication or heart surgery. For edema associated with lung disease, quit smoking . If edema is caused by liver disease, avoid alcohol intake. In some cases, edema may be treated by flushing fluids out of the body, i.e., paracentesis for ascites.

Nutrition/Dietetic concerns

Since salt causes or aggravates fluid retention, decrease salt intake. Certain foods including alcohol, caffeine , and chocolate may increase edema. Consult a physician about discontinuing medication that may be causing edema. Maintain an optimal weight since being overweight decreases blood circulation and exerts increased pressure on the veins.

Therapy

For mild cases of peripheral edema symptoms may be decreased by elevating the lower extremities

QUESTIONS TO ASK YOUR DOCTOR

• How do I know if the swelling I have is normal swelling or edema?
• What places me at risk for edema?
• What tests will be used to diagnose edema?
• What is causing my edema?
• What will be used to treat my edema?
• Will there be any side effects from treatment?
• What lifestyle changes to I need to make to help prevent edema?
• Will edema return after treatment?
• Will I always be at risk for developing edema?

Prognosis

The prognosis for edema depends on the underlying cause. For most people, the prognosis is good.

Prevention

Change positions frequently throughout the day. Perform regular physical exercise . Physical activity stimulates return of excess fluid in the tissues back into the circulatory system. Decrease salt intake.

Caregiver concerns

Protect areas of edema from pressure, injury, and extreme heat or cold. Report, immediately to a health care provider, any area of edema that is red, has any open sores, or is painful.

Resources

Ascites: A Common Problem in People with Cirrhosis. http://www.gi.org/patients/gihealth/ascites.asp

Diseases and Conditions Swelling. http://www.pdrhealth.com

Edema. www.clevelandclinic.org

Edema. http://www.healthatoz.com

Edema. http://www.intelihealth.com

Edema. http://www.medicinenet.com/edema/article.htm

Edema. http://yourtotalhealth.ivillage.com/edema.html

Medical Encyclopedia: Swelling. www.nlm.nih.gov

Patient Information: Edema. http://patients.uptodate.com/topic.asp?file=kidn_dis/4639&title=Edema

June G. Borazjani R.N., M.S.N., C.P.H.Q.