Edema is the medical term for swelling. It means there is extra fluid in the tissue. There are many ways in which the body can retain excess fluid.
One such way is when we have an injury there will be an inflammatory reaction that contributes to edema. Also, an allergy can certainly activate the inflammatory response and cause edema.
The most common source of edema, however, is known as “venous insufficiency.”
The veins have a unique system of valves. These valves allow the blood returning to the heart to flow against gravity. The main driving force of blood in our veins is the compression of our calf muscles on the veins. This is called the “muscle pump.”
When we inhale and create negative pressure in our chest, it helps drive the blood in our veins back to the heart.
People who have venous insufficiency have poor functioning valves. Heredity is the primary reason for poor functioning valves. Other causes include trauma and issues related to hormonal changes during pregnancy.
Veins with dysfunctional valves carry blood downward toward the feet with gravity rather than against it. Over time there is a tremendous increase in pressure of those veins; this pressure forces fluid through the vein wall into the surrounding tissue, causing edema.
An additional fluid system in our legs is called the lymphatics. This is an important part of our immune system and helps filter out germs through the lymph nodes and other lymphatic organs.
When you have an injury, it is the lymphatic blockage that slows flow and contributes to swelling. Over time the lymphatics become less blocked or create new channels with improved flow resulting in less edema.
In some circumstances, lymphatics are permanently scarred. This is called lymphedema and involves the feet, whereas venous insufficiency, typically, does not.
Lastly, another common cause of swelling is the heart not working as an efficient pump. With age, the heart loses some of its ability to stretch and squeeze as well as it should. The walls of the chambers of the heart stiffen up. This can be further aggravated with a heart attack.
The lack of pumping ability of the heart leads to fluid backing up and being forced out into the tissue. This is known as congestive heart failure.
So, edema can be a complex mixture of several contributing factors: inflammation, venous insufficiency, lymphedema, and congestive heart failure.
How can you help alleviate swelling in your feet and legs? The most common two methods are to elevate your legs above the level of your heart and the use of compression stockings.
An evaluation by a specialist in vascular medicine can help differentiate which contributing problem is the most responsible and prescribed treatments can help control or even eliminate the edema that may be present.
Seek counsel from your health care provider to help define which cause is unique to you and which treatment can best serve you. ☸
(Dr. Mark Peterson of Willamette Vascular Specialists is board certified with specialty training in vascular surgery. He has been serving Salem area communities for more than 30 years.)