THE FOUR STAGES OF WOUND HEALING

    OVERVIEW
A wound is a form of injury which is caused by external trauma. This trauma causes the skin membrane to break and causes tissue damage. There are mainly two types of wounds: acute and chronic. The healing process of both follows the same trajectory. However, chronic wounds take more time due to complications. 

The four dynamic stages of wound healing are as follows.

 STEP 1: HEMOSTASIS 
 

Hemostasis can simply be described as the process of clotting. As soon as the brain receives the signal of being wounded, it rushes the supply of platelets to the affected body parts blood vessels. Bleeding is expected to have started by now. Platelets now flow in the blood flowing out of the body and make use of its adhesive property, stick around and act as a platelet plug. 

It is a four-step process that brings bleeding to a halt:

·         Narrowing down the blood vessel.

·         Primary platelet plug.

·         The initiation of clot formation is known as the coagulation cascade.

·         Complete clot formation is only possible if no internal or external factors have disturbed the initiation of clotting.

However, if the trauma was harmful enough but did not cause a physical wound, the brain would still recruit the platelets which will do their job. This creates internal clots which in itself is a problem.

 
STEP 2: INFLAMMATORY 
Inflammation is caused by triggers sent to ones immune system regarding cell or tissue damage. Hemostasis is responsible for stopping blood from moving out of the blood vessel, inflammation on the contrary is responsible for stopping the external elements from moving inside the vessel. These external elements may include bacteria, debris, or chemicals.

The wound area receives an influx of phagocytic cells, which are a type of white blood cells. These act like a mob of guards around the wound. Their job is not only to prevent the external bacteria from invading but also to move out the pathogens that were inside or around the injured area. This is to allow the damaged tissue to heal without any agitation.

Inflation may take as many as seven or more days depending on the severity of the wound. Inflammation may cause the following conditions:

·         Heating sensation.

·         swelling.

·         Pus formation.

·         Painful to touch.

STEP 3: PROLIFERATIVE 
Now that the wound has been guarded, it is time for the wounded body part to be repaired. This stage involves four major courses of action:

·         Formation of new tissue in presence of collagen. A collagen is a form of protein. Its job is to provide structural support to the tissues. 

·         Myofibroblasts start the process of tissue granulation. Tissue granulation in simple words is the process of joining the edges of the tissue that has been torn apart.

·         The disrupted network of blood vessels is to be mended. This ensures that the tissue under repair receives sufficient nutrients.

·         The final stage is the unification of all three elements mentioned above. This ensures that the resurfacing is coherent.

STEP 4: MATURATION
 

Maturation, also known as Remodeling, is the most prolonged phase of the whole process. It has two main jobs:

1.    Remodeling: the process in which the healed area starts to develop elasticity.

2.    Apoptosis: Disposing of the dead cells. These dead cells belong to the damaged or worn-out tissue that was beyond repair.

However, it is important to note that the newly repaired surfaces tensile strength is weakened by 20% which requires the granulation tissue to come into action. The granulation tissue may cause scarring that may fade or may not fade with time. Collagen plays a vital role in this stage.

 INFLUENCES ON THE RATE OF HEALING
These are expected standard stages of wound healing. However, the progression may be disturbed or come to restart any of the phases due to intrinsic or extrinsic factors. These factors require medications to be eliminated.

Intrinsic Factors:
The rate of healing depends on the persons overall health condition. A strong immune system can speed up the process of recovery. On the other hand, chronic conditions can develop complications. Some of the conditions are as follows:

·         Obesity Ischemia is the nature of obesity that causes the inconsistent flow of oxygen. Lack of proper oxygen may disrupt the healing process at any stage.

·         Cancer tendency The maturation stage requires getting rid of dead cells. If the body fails at this function it may turn into cancer tumors. 

·         Chemotherapy and Radiation survivors Both treatments tend to weaken the immune system. 

·         Diabetes  This ailment mainly affects the proliferative stage.

·         Lack of Collagen It is the physical substance required to bring healing to practice. Old-age, weak metabolism, and malnutrition can lead to inadequate collagen production.

Extrinsic Factors:
 

Improper medication and negligence in protecting the wound can also lead to complications: 

·         Physical exertion

·         Lack of hygiene.

·         Chemical exposure.

·         Lack of topical moisture.