Edema

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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.