Patrick Shanahan, age 11, of Gary, Indiana, for his question:
How does fluid get into a blister?
Patrick went roller skating and got himself a blister as big as a half dollar. No doubt it was the ordinary type blister that forms when a piece of skin is inured by pressure or chafing. As we all know, this sort of surface wound is very sore. It also requires a lot of patient pampering until the fluid inside the bubble subsides.
The epidermis is an outer layer of dead cells designed to protect the sensitive living cells in deeper layers of the skin. The cells of living tissues are filled and surrounded with liquids. These are the fluids that seep in to fill a blister. An ordinary blister forms when surface tissues are bruised or irritated. Its fluid oozes from surrounding cells and forms a liquid filled bubble between the outer epidermis and the living layers of skin below.
No doubt the body is striving to protect the injured tissue while its damaged cells are healing. It is so sore that the victim has to remove the pressure and stop irritating the tender spot. However, the fluid does more than protect the wounded cells and warn against further damage. Its liquid contains lymph material. And lymph is a soothing solution that helps to sustain all the living cells. It transports various dissolved nutrients plus an array of vital biochemicals needed for cellular activities. It also carries magical substances that fight infection and assist in the healing process.
The cell walls of living tissues are thin and permeable. They also can select the useful solutions and allow them to seep through the tissue to places where they can help. When the skin area is damaged by pressure and chafing, cellular solutions seep around the injured spot, soothing it and perhaps causing it to swell. Then more liquid seeps in to fill a blistery bubble above the wound and under the protective epidermis.
It seems a shame to ignore the body's skillful effort to protect and heal. What's more, when we do, we risk penalties. The sensible thing is to work with nature and do what we can to add more protection to the fragile blister. When possible, it is wise to add a stiffish bandage of some kind. This adds an extra shield from further damage.
But sometimes a blister gets broken by accident. This calls for immediate treatment. Swab the wound with antiseptic and apply a soothing salve. These substances, will help to do the lost blister's work of soothing and germ fighting. Add a strong bandage to do the protective work.
It is not wise to prick a blister to release its fluid. It will not reduce the soreness and the needle you use may cause more trouble. If the blister is on a foot and prevents the victim from getting about, it should be treated by a doctor or his assistant. The healing process calls for patience because injured cells are being rebuilt. New cells are built over the wound and when the blister's work is done, the top of the bubble dries up and peels away leaving a patch of slightly sensitive new tissue.