Home » Infections » Wound Healing Stages – Types, Phases I, II, III, IV

Wound Healing Stages – Types, Phases I, II, III, IV

Written by Dr.Mary

What are the Stages of a Wound healing?

A wound of any type is a skin break – the outer skin layer is referred to as epidermis. Wounds are in most cases cause by scrapes or cuts. Wounds of different types can be treated in different ways from one another, dependent on how the wound occurred and how severe the wound is.

Healing of a wound is the body’s response to an injury and this sets into motions events that involve four (4) phases. These stages of the healing process are complex and the aim of this process is to restore the cellular structures and layers of tissue. This process can continue for months to years.

Wound Healing Phases

There are four (4) basic phases of the process of healing and these include:

Phase I – Inflammatory

The phase starts with the initial injury. Here there will be bleeding, narrowing immediately of any blood vessels involved, formations of clot and the release of a variety of chemical elements into the wound starting the process of healing. Specialized cells of inflammation will clean the wound of any debris and last for several days.

Phase II – Proliferative

This is when a latticework or matrix of cells form. On this latticework or matrix, new blood vessels and new cells of skin form. It’s these new vessels that are small – capillaries – and give a wound that is healing and has the pink or red-purple look. These new vessels supply the cells for rebuilding with nutrients and oxygen in order to withstand the growing of the new cells as well as supporting the production proteins which are primarily collagen. This collagen acts as the framework on which any new tissues build and is the substance in final scars that is most dominant.

Phase III – Remodeling phase

This phase normally starts after two (2) to three (3) weeks. The collagen framework is in the process of becoming more organized giving the tissue its strength. The density of the blood vessels becomes reduced and the wound starts to lose its pink color. Over a six (6) month period, this area continues to increase in strength ultimately attaining approximately 70% of the strength of skin that has not been injured.

Phase IV – Epithelialization

This is the procedure of laying down epithelial cells or new skin. This skin acts as a barrier that is protective between the body and the outer environment. Its main function is to protect against bacteria as well as excessive loss of water. The rebuilding of this layer starts within several hours of the wound and is completed within 24 to 48 hours with a clean, stitched or sutured wound. Wounds that are open may take seven (7) to ten (10) days because the process of inflammation is extended which adds to scarring. Scarring happens when any injury spreads past the deep skin layer or the dermis.


Types of Wounds

Types of wounds include:

Scrapes as well as Abrasions

Scrapes as well as abrasions are surface or superficial wounds. The skin layers that are deeper are unbroken and bleeding is mostly a slow ooze. Normally these type wounds are caused by rubbing or friction alongside a rough surface.

Cuts or Lacerations

Cuts or lacerations go thru all the skin layers as well as fat or the deeper tissues. Bleeding can be more severe or brisk. Severe hits by an object that is blunt, falls on a solid surface or contact with objects that are sharp are the more common causes of cuts.

Puncture Wounds

Puncture wounds are normally the result of a pointed object that is sharp entering the skin. Most examples are being stuck by a needle, stepping on a nail, or obtaining a stab with a knife. Bleeding is normally minimal and these wounds might be hardly noticed.

Animal Bites or Human Bites

Animal bites or human bites can be lacerations puncture wounds, or a grouping of both. These are the type of wounds that are at all times tainted by saliva and need extra care.

Most wounds heal very well when given proper care. The overall rate of infection is approximately 6.5%. Redness around the wound, a red line extending from the wound towards the body or any drainage that is yellowish from the wound are all signs of infection and need re-evaluation immediately by a doctor.

Leave a Reply

Diseases and Conditions