Wounds — breaking the skin surface — can be caused by many things, from accidents to surgeries, but the body’s process of healing is common to all.
Stages required for healing include stopping of blood loss from the wound (hemostasis), temperature increase accompanying the action of antibodies (inflammation), rebuilding of cells inside the wound (proliferation) and finally rebuilding surface cells to restore skin strength (remodeling).
Any of these stages can be slowed or interrupted by external or internal causes. If a wound is too dry, cells can dehydrate and die, causing a scab or crust, slowing healing. If an infection occurs or excessive bacteria are present, pus will form, requiring drainage, keeping the wound from closing.
If the skin is too moist, the tissue will soften and break down, slowing healing. This happens commonly in the presence of fecal or urinary incontinence.
After any wound, skin and underlying tissue cells may die, usually due to loss of blood supply. This tissue must be removed.
Restoring blood supply to wounded tissue is critical for healing. Pressure, constriction or swelling reduces blood flow, slowing the process.
Internal factors, such as age, hormones, stress, diabetes, alcoholism, smoking, poor nutrition, obesity, and certain medications can also impede wound healing.
Wounds that heal too slowly or incompletely often produce abnormal scarring, and what are called “keloids.” Keloids are lumpy scars that can extend past the area of the original wound. Similarly, contracture scars can form, which pull the skin surface tighter than it was before the wound.