Doc: Leaking lymph causes lower-extremity swelling
Dear Dr. Roach: Forty-five years ago, I had ovarian cancer. I had surgery, followed by 30 radiation treatments. Twenty years later, I was diagnosed at first with venous insufficiency, then with lymphedema in my lower extremities.
I was on spironolactone for 15 years before I was told that a diuretic does nothing for either condition, so I stopped taking it. I wear compression stockings and get manual lymphatic drainage treatments as needed.
What is the difference between venous insufficiency and lymphedema? What is the role of sodium intake in both? Is there a cure for venous insufficiency?
Dear O.M.L.: The systemic arteries take oxygen-rich blood from the heart’s left ventricle to the body, and the veins carry the oxygen-depleted blood back to the heart.
However, veins leak a little bit. They don’t leak blood cells, but they do leak fluid. This fluid (called lymph) tends to collect in places where it is pulled by gravity.
Most adults have had the experience of having some swelling in the feet or fingers, especially after a hot and humid day, with a lot of standing or after taking in high amounts of salt and water.
The body uses the lymphatic system to return this fluid to the heart. Thin-walled lymphatic vessels — which, roughly speaking, parallel the veins — return excess fluid leaked out by blood vessels back to the heart.
In venous insufficiency, the veins leak more than they ought to. This is often because the valves in the veins, which should prevent blood from going the wrong way, become damaged and “insufficient.”
By contrast, in lymphedema, the lymphatic vessels are damaged. Radiation and cancer are common causes, but it sometimes happens for no known reason.
Diuretics, like spironolactone, furosemide (Lasix) and HCTZ are not an effective long-term treatment for either condition. Support stockings, keeping the affected area elevated above the heart (a half-hour three times daily is usual), and avoiding excess sodium are appropriate for both conditions.
Manual lymphatic drainage is the most effective treatment for lymphedema, but it is labor-intensive, often not covered by insurance and can be hard to find.
Email questions to ToYourGoodHealth@med.cornell.edu.