What Causes Swelling?
When we experience swelling it isn’t very fun. With it come pain, discomfort, and the inability to move properly.
Let’s take a quick look at the processes that cause swelling so that we can better understand how to relieve it.
Normal Tissue
Pictured below is a small piece of normal tissue made up of cells. On either side are the arteries and veins that support the tissue.
The purple sections between the arteries and veins are called capillaries.
Capillaries are special structures that allow nutrients from the blood to come out to feed tissues.
(The whole reason that we have a blood stream is for nutrient delivery to the cells. It’s kind of like “Door Dash” for the cells.)
The green structure is the Lymphatic Capillary. Lymphatic capillaries are responsible for draining the waste from the cell.
Cells Being Fed
Notice the special vessels colored purple in the diagram. These are called capillaries, and they join the arteries and veins.
Capillaries have little “windows” that allow substances to pass through from the blood stream to the cells. For our cells to get food, it is carried out of the bloodstream by fluid.
Our cells eat and poop just like we do, which leaves waste behind. This waste and the fluid that carried the food to the cells are picked up by the lymphatic system.
The Two Circulatory Systems
The Lymphatic System is a second circulatory system in the body.
Most of us learned about the primary circulatory system which includes the heart, arteries, and veins.
Note how the two systems look very similar next to one another. This is not accidental.
Food is constantly being delivered to the tissues throughout the body, and the cells are constantly producing waste.
The fluid and waste have to go somewhere. They can’t hang out in the tissues, so the lymphatic system picks them up and returns them to the heart, putting them back into the bloodstream.
Swelling
If, for some reason, the fluid can’t be removed from the tissue by the lymphatic system (pictured in green), swelling results.
Swelling can happen as a result of injury to the body – like slamming your hand in a car door or from surgery. In this instance swelling acts like a natural splint to keep the body immobile so you can’t hurt yourself further.
Swelling can also be caused by a blocked lymphatic system (the drain).
Swollen Tissue
Chronic Venous Insufficiency (CVI)
Another cause of swelling is faulty valves in veins. When valves fail, gravity pulls the blood back down the leg.
This causes extra seepage of fluid out of the capillaries. When this happens, the lymphatic system can’t keep up with all of the extra fluid load and swelling results.
This condition is called Chronic Venous Insufficiency (a.k.a CVI or Ambulatory Venous Hypertension). It is common and is often found in people who stand a great deal.
Lymphedema
Lymphedema is a common type of swelling for people who have had cancer surgery. It is caused when lymph nodes are removed either to test to see if cancer has spread (usually 1-3 nodes) or because cancer is found in the lymph nodes and they are all removed in an area.
This is like having a bridge collapse on a major interstate highway. There is lots of traffic, but the cars can’t go past the damaged area.
You may be familiar with Lymphedema and just not know what it is called. If you know someone who has had breast cancer and after their surgery they have to wear a special sleeve, this is to help prevent the swelling from Lymphedema.
In rarer instances people can be born with a poorly formed lymphatic system which causes them to have Lymphedema.
