How does the body heal a skin wound without bleeding? I had a wound in which thick layer of skin was gone and which was too painful to touch. I could see the wound secreting clear liquid rather than forming a scab like in a blood wound. What is this yellowish thick liquid being secreted and does it form new skin?
Skin is composed of layers, the uppermost being the epidermis. Upper layers of the epidermis (dry, flat cells tightly packed together, and of varying thickness on different parts of the body) can be abraded off, leaving deeper layers of the epidermis (nearer to underlying blood vessels) exposed. Since peripheral nerve endings do exist in this area, the wound is painful. A wound that does not extend into the dermis does not bleed (for example, a second degree burn can lift the upper layers of the epidermis from the deeper layers; no blood will collect in the blister, but the wound is painful. Peel off the top of the blister, and you have an analogous situation.
Because the surface of the skin is no longer present, fluid (as with a blister, not containing red blood cells) leaks from the blood vessels. Initially a transudate, it can also be an exudate. And, no, it does not contain the cells needed to regenerate the upper layers of the skin. It contains many of the proteins found in serum and may contain white blood cells which help to fight off infection.
New cells are generated from the deeper cell layers (the basal cells) which are still intact. They grow from the bottom of the wound up, so to speak. The scab formed by the dried fluid keeps the layer under it moist, providing a good environment for cell growth.