Edema - Causes, Symptoms and Treatment

Edema is an observable swelling from fluid accumulation in certain body tissues. Edema, which used to be called dropsy when it involved the whole body, means abnormal fluid retention in body tissues, producing swelling. It is not a disease in itself but sometimes may be a symptom of disease or injury. Also, it can come from causes unrelated to injury or illness.

Edema of the ankles and feet is quite common, especially among people on their feet a lot, and disappears with rest. Edema of the ankles can also stem from tightness around the legs (as from garters or rolled stockings) or constriction of the thighs (by tight underclothing). When edema is constriction caused, it is only necessary to remove the constricting garment and avoid further use.

Pulmonary edema (American English) or oedema (British English) is swelling and/or fluid accumulation in the lungs . It leads to impaired gas exchange and may cause respiratory failure . It is due to either failure of the heart to remove fluid from the lung circulation ("cardiogenic pulmonary edema"), or due to a direct insult to the lung parenchyma ("noncardiogenic pulmonary edema").

Edema most commonly occurs in the feet and legs, where it also is referred to as peripheral edema. The swelling is the result of the accumulation of excess fluid under the skin in the spaces within the tissues that are outside of the blood vessels. Most of the body's fluids that are found outside of the cells are normally stored in two spaces; the blood vessels (where the fluids are called the blood volume) and the interstitial spaces (where the fluids are called the interstitial fluid). In various diseases, excess fluid can accumulate in either one or both of these compartments.
Edema, however, can also be an indication of beginning heart, kidney, or liver disease. And repeated episodes of ankle or other swelling, or an episode that lasts more than a day or two, should be investigated by a physician.

Treatment of Edema

Treatment of edema focuses on correcting the cause of the fluid accumulation. When circulatory causes have led to pulmonary edema, treatment with intravenous nitrates ( glyceryl trinitrate ), and loop diuretics , such as furosemide or bumetanide , is the mainstay of therapy. These improve both preload and afterload, and aid in improving cardiac function. Depending on your condition and the reason for your pulmonary edema, you may also receive one or more of the following medications:

• Furosemide (Lasix). This diuretic works quickly to expel excess fluid from your body in cases of cardiac pulmonary edema.
• Morphine (Astramorph, Roxanol). This narcotic, for years a mainstay in treating cardiac pulmonary edema, may be used to relieve shortness of breath and associated anxiety. But some doctors now believe that the risks of morphine may outweigh the benefits and are more apt to use other, more effective, drugs.
• Afterloaders. These are drugs that dilate the peripheral vessels and take a pressure load off the left ventricle.
• Aspirin. Your doctor may recommend starting aspirin therapy if you're not already taking it. Aspirin helps thin the blood so that it moves through your small blood vessels more easily.
• Blood pressure medications. If you have high blood pressure when you develop pulmonary edema, you'll be given medications to control it. On the other hand, if your blood pressure is too low, you're likely to be given drugs to raise it.
• If you have mild leg edema caused by venous insufficiency, elevate your legs periodically and wear support (compression) stockings. Sometimes surgery is needed to improve the flow of blood through the leg veins.