What is Edema?

Edema is an abnormal and excessive accumulation of interstitial fluid within tissues as a result of movement of the fluid from the vasculature into the interstitial spaces. Depending on fluid composition, edema fluid can be transudate (low protein), or exudate (high protein).

Extravascular fluid may accumulate in body cavities such as the pleural, the pericardial, or the peritoneal cavity. Depending on its severity and location, the effect of edema may range from minimal effect to profound and fatal.

Causes of edema

1. Congestive heart failure
2. liver diseases like Ascites (liver cirrhosis)
3. Venous obstruction
4. Thrombosis or blood clots
5. Lower extremity inactivity
6. kidney diseases
7. Lymphatic Obstruction
8. Excessive salt intake with renal insufficiency
9. Inflammation
10. Increased renin-angiotensin-aldosterone secretion

Types of edema

The edema is of 2 main types:

1. Localized is limited to an organ or limb e.g. lymphatic edema, inflammatory edema and allergic edema.
2. Generalized (anasarca or dropsy) is systemic in distribution, it’s found in subcutaneous tissues e.g. renal edema, cardiac edema and nutritional edema.

There are also a few different types of edema include:

• pulmonary edema is accumulation of excess fluid in the lung, it may cause death due to interfering with normal ventilatory function and impeding oxygen diffusion, alveolar edema fluid also creates a suitable environment for infection.
• cerebral edema or swelling of brain (brain edema) is the most threatening type of edema. With increased intracranial pressure, the vascular supply to brain stem may be compressed, and it’s of three types:
  • vasogenic edema
  • cytotoxic edema
  • interstitial edema

Edema Treatment

severe edema can be treated with drugs that help the body to get rid of excess fluid in the form of urine (diuretics).

Long-term management of edema usually involve treating the cause of the swelling for example a lymphatic obstruction that causes edema is removed with surgery.

If edema occurs as a result of a medication, then the doctor should check for an alternative drug that doesn't cause edema.