Wound Healing Phases

Definition of wound is partially lost or damaged body tissue.

Causes of Wound: trauma of sharp or blunt objects, temperature changes, chemicals, explosion, electric shock, or animal bites.

Wound Forms: cuts, puncture wounds, lacerations, abrasions, burns and others.

Wound Healing phases are as follows:

1. Inflammation Phase

It occurs since the injury until about the fifth day. Severed blood vessels in the wound will cause bleeding, and the body tries to stop it with vasoconstriction, shrinkage in broke up vessel edges (retraction), and hemostasis reaction. Hemostasis occurs because platelets out of the blood vessels attach to each other, and together form fibrin net, freeze the blood from the blood vessels. Adjacent platelets will granulate, release chemoattractant pulling inflammatory cells, and activate local fibroblasts and endothelial cells as well as a vasoconstrictor. Meanwhile, the inflammatory reaction happens.

After hemostasis, coagulation process will activate complement cascade, and then it will be released bradykinin and anaphylatoxin. Clinical signs and symptoms of inflammatory reaction become clear, in the form of redness due to dilated capillaries (rubor), warm sense (heat), pain (dolor) and swelling (tumor).

2. Proliferation Phase

It is called fibroplasia phase because the prominent part is proliferation of fibroblast.

It takes place from the end of inflammation phase until about the end of the third week.

Collagen fibers are formed and destroyed again to adjust the tension on the wound which tends to shrink. This trait together with miofibroblast contractile trait cause the pull on the wound edges.

The wound is filled by inflammatory cells, fibroblasts, and collagen, and the formation of new blood vessels (angiogenesis), forming reddish tissue with smooth protruding surface called granulation tissue.

With the covering of the wound surface, fibroplasia process with the formation of granulation tissue will also stop and start the process of maturation in remodeling phase.

3. Remodeling Phase

Maturation process happens which consists of re-absorption of the excess tissue, proper shrinkage according to the gravity, and finally re-formation of new tissue. Body tries to re-normalize all abnormal things because of healing process. Edema and inflammatory cells are absorbed, young cells become mature, new capillaries close and reabsorbed, excess collagen is absorbed and the rest shrinks according to the amount of strain. During this process, it is resulted pale scar tissue, thin, and flexible, and easily moved from the base.

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