Edema is a symptom that has many possible causes

August 2012

DEAR DOCTOR K: What can I do about my edema? The diuretics my doctor prescribed haven't helped.

DEAR READER: Edema is swelling caused by a buildup of extra fluid. Edema most often affects the feet and legs, but it can affect the hands and even the face. The skin becomes puffy and swollen.

The fluid in your body is in three places: inside each of the 13 trillion cells in your body; in the blood (which means inside all your blood vessels); and in the space between your cells and your blood vessels. Edema occurs when unusual amounts of fluid leak out of the blood vessels and into the space between your blood vessels and cells.

Diuretics, also known as water pills, are often used to treat edema. They help your kidneys eliminate excess fluid in your body.

Edema is a symptom that may be caused by many conditions. Your doctor will need to identify and treat the condition that is causing it. Possible causes include:

-- Prolonged standing or sitting. This can cause edema in your feet and lower legs. That's because gravity is pulling more blood into the blood vessels of your legs. When the blood vessels swell with fluid, some of the fluid leaks out of the vessels and into the tissues.

-- Venous insufficiency from varicose veins. Valves inside the veins of the legs weaken, making it more difficult for the veins to pump blood back to the heart. This leads to fluid buildup.

-- Severe chronic lung diseases. Emphysema and chronic bronchitis weaken the heart's ability to pump, particularly the right side of the heart.

-- Congestive heart failure. The left or right side of the heart can no longer pump efficiently.

-- Pregnancy. The enlarged uterus with the fetus inside can pinch off the veins carrying blood from the legs to the heart.

-- Pre-eclampsia. This serious condition can occur during pregnancy.

-- Low blood-protein levels. These can be caused by malnutrition, kidney and liver disease.

As for treatments, increasing the dose of your diuretic might solve the problem. A low-salt diet usually helps, since salt causes the body to retain fluid. You also should avoid drinking too much fluid.

If the edema is in your feet and legs, prop them up whenever you are sitting. This counters the effect of gravity and encourages more blood to move out of your legs. Compression stockings can help squeeze the edema fluid out of your tissues. Finally, if your edema is caused by varicose veins, traditional surgery or newer laser procedures can treat the condition.

It's important to protect feet and legs swollen by edema from pressure, injury and extreme temperatures. The skin over swollen legs becomes more fragile over time. Cuts, scrapes and burns in areas that have edema take much longer to heal and are more likely to get infected.

(Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, Mass. 02115.)

Souix City Journal

Pathophysiology and treatment of edema following femoropopliteal bypass surgery.

Sept  2012

Te Slaa A, Dolmans DE, Ho GH, Moll FL, van der Laan L.

Source

Department of Surgery, Amphia Hospital, Breda.

Abstract

Substantial lower-limb edema affects the majority of patients who undergo peripheral bypass surgery. Edema has impairing effects on the microvascular and the macrovascular circulation, causes discomfort and might delay the rehabilitation process of the patient. However, the pathophysiology of this edema is not well understood. The Cochrane Library and Medline were used to retrieve literature on edema following peripheral bypass surgery. Factors other than local wound healing alone are suggested in the literature to play a role, given the severity and duration of this edema. Hyperemia, microvascular permeability, reperfusion-associated inflammation and lymphatic disruptions are likely to facilitate the development of edema. 

Preventive methods could be lymphatic-sparing surgery, intraoperative antioxidative therapy and postoperative elevation. Successful treatment strategies to reduce postoperative edema are based on lymph massage and external compression. 

In conclusion, the pathophysiology of edema following peripheral surgery is not fully understood, although reperfusion-associated inflammation and lymphatic disruptions are likely to play a crucial role. When future less-invasive techniques prove to be successful, postoperative edema might be minimized. Until then, a careful lymphatic-sparing dissection should be executed when performing a peripheral bypass reconstruction. Postoperatively, the use of compression stockings and leg elevation are currently the golden standards.

Vascular