Untitled Document
The definition of edema is observable swelling from fluid accumulation in body tissues. When parts of the body are affected with edema, they are considered edematous. Edema most commonly occurs in the feet, ankles, legs, and/or hands where it is referred to as peripheral edema. Edema of the foot is sometimes called pedal edema. The swelling is the result of the accumulation of excess fluid under the skin in the spaces within the tissues.
All tissues of the body are made up of cells, blood vessels, and connective tissues that hold the cells together called the interstitium. Most of the body's fluids that are found outside of the cells are normally stored in two spaces; the blood vessels (as the "liquid" or serum portion of your blood) and the interstitial spaces (not within the cells). In various diseases, excess fluid can accumulate in either one or both of these compartments.
The body's organs have interstitial spaces where fluid can accumulate, and there are a number of different types of edema. An accumulation of fluid in the interstitial tissue around the air spaces (alveoli) in the lungs occurs in a disorder called pulmonary edema. In addition, excess fluid sometimes collects in what is called the third space, which includes cavities in the abdomen (abdominal or peritoneal cavity - called "ascites") or in the chest (lung or pleural cavity - called "pleural effusion"). Anasarca, also known as extreme generalized edema is severe, widespread accumulation of fluid in the all of the tissues and cavities of the body at the same time.
What are the types of edema?
The information provided here is about edema on the legs and feet (pitting or peripheral edema); however, other forms of edema are typically named depending on what part of the body is affected.
Cerebral edema is an accumulation of excess fluid in the brain.
Angioedema is swelling underneath the skin. Unlike hives, which affect the surface of the skin, angioedema affects the deeper layers of the skin and often occurs on the face.
Hereditary angioedema is a rare genetic condition that causes the capillaries to release fluids into surrounding tissue, which results in edema.
Papilledema is swelling of the optic nerve of the eye that is a result of pressure inside the skull and around the brain (intracranial pressure).
Macular edema is a swelling of the portion of the eye that perceives central, detailed vision (the macula).
Dependent edema usually is edema of the legs and lower body, which is affected by gravity and is dependent on a person's position. This edema usually occurs in the legs when a person is standing, and in the buttocks and hands if a person is lying down.
Scrotal lymphedema is an enlargement of the scrotum due to fluid accumulation around the testes.
Lipedema is a disorder of the fatty (adipose) tissue that causes swelling of the legs and hips, and can lead to lymphedema.
Leg Swelling: Symptom of Pitting Edema
Leg swelling generally occurs because of an abnormal accumulation of fluid in the tissues of the lower extremity. Persisting indentation of a swollen leg after pressure from a finger is known as pitting edema. Common causes of leg swelling include
- • salt retention,
- • cellulitis,
- • congestive heart failure, and
- • medication side effects.
What is pitting edema?
Pitting edema can be demonstrated by applying pressure to the swollen area by depressing the skin with a finger. If the pressing causes an indentation that persists for some time after the release of the pressure, the edema is referred to as pitting edema. Any form of pressure, such as from the elastic in socks, can induce pitting with this type of edema. This type of edema may be normal depending on the severity. Almost everyone who wears socks all day will have mild pitting edema by the end of the day.
What are the symptoms of pitting edema?
Symptoms of pitting edema include swelling, which causes the skin surrounding it to tighten, the position that you are in will affect edema, and the skin over the swollen area appears shiny and light, and, often when a finger is placed on the swollen area and indentation is left on the skin.
What causes pitting edema?
Edema is caused by either systemic diseases, that is, diseases that affect the various organ systems of the body, or by local conditions involving just the affected extremities. The most common systemic diseases associated with edema involve the heart, liver, and kidneys. In these diseases, edema occurs primarily because of the body's retention of too much salt (sodium chloride). The excess salt causes the body to retain water, which then leaks into the interstitial tissue spaces, where it appears as edema. Medications also can cause pitting edema.
The most common local conditions that cause edema are varicose veins and thrombophlebitis (inflammation of the veins) of the deep veins of the legs. These conditions can cause inadequate pumping of the blood by the veins (venous insufficiency). The resulting increased back-pressure in the veins forces fluid stay in the extremities (especially the ankles and feet). The excess fluid then leaks into the interstitial tissue spaces, causing edema.