The inflammation phase starts as soon as the wound has occurred and is the body’s natural response to the injury. Blood vessels contract in the wound bed and a clot is formed. This process is known as haemostasis. Following this, the blood vessels will eventually dilate to allow white blood cells, growth factors, enzymes to break down any bacteria and dead tissue in the wound.
There may be large amounts of exudate produced in the wound and the patient will feel pain. The inflammation phase lasts typically 4-5 days in acute wounds, whereas this phase will last longer in chronic wounds.
This phase starts when the wound surface is clean and the inflammation stage is almost complete. Reconstruction and closure of the wound then occurs. Granulation tissue is now red and fresh with an abundant blood supply. Epithelialisation creates a new surface on the wound by a process in which epidermal cells divide and migrate from the wound margin across the wound bed.
Pale or dark granulation can indicate poor perfusion, ischaemia or infection.
Maturation occurs when the wound closes. Epithelial cells will have grown in from the wound edges and cover the wound. During maturation the collagenous fibres in the wound are converted into a coarser fibre, with a better structure. The tissue becomes flattened and less red and elevated. The eventual scar tissue will only have about 70-80% strength of the original tissue.