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Wound

life science Maturity 11-13 Next article →

A wound is any disruption of or damage to living tissue. This damage can affect the skin, mucous membranes, or internal organs. Wounds can happen suddenly due to direct trauma. This trauma might be mechanical, thermal, or chemical in nature. Other wounds develop slowly over time. These are often caused by underlying disease processes. Because wounds vary so much, healthcare professionals must evaluate them carefully. They look at the location, depth, and timing of the injury. They also check the sterility of the wound bed to plan treatment.

In a healthy body, all wounds follow a specific healing process. This process consists of four distinct stages. The first stage is hemostasis, which occurs minutes to hours after the injury. This step works to stop bleeding. The second stage is the inflammatory phase, which typically lasts 1 to 3 days. Next comes proliferation, the third stage. This stage lasts from a few days up to a month. The final stage is tissue remodeling, also called scar formation. This phase usually lasts 12 months but can continue for up to 2 years.

A Surgeon Applying a Suture
A Surgeon Applying a Suture

Acute wounds are those that result from direct trauma and follow the expected healing timeline. They are categorized as either open or closed. An open wound occurs when the skin is broken and underlying tissue is exposed.

A skateborder falls off his board and cuts his hand
A skateborder falls off his board and cuts his hand

Examples include abrasions, which are superficial scrapes of the epidermis. Incisions are clean cuts made by sharp objects like knives. Puncture wounds occur when an object like a nail enters the skin. Avulsions are more severe, where a body structure is forcibly detached. Closed wounds involve damaged tissue but leave the overlying skin intact. A hematoma is a closed wound where blood collects under the skin.

Treatment of wound with lance grit
Treatment of wound with lance grit

Chronic wounds are different because they are arrested or delayed during the healing process. A wound is often considered chronic if it has not progressed for over three months. These wounds frequently result from a disruption in the inflammatory phase. Many chronic wounds are caused by diabetes mellitus. In people with diabetes, up to 25% may experience non-healing wounds in their lifetime. Other causes include venous or arterial insufficiency. This happens when blood flow into or out of a limb is impaired. Immunologic diseases, such as lupus, can also cause wounds to be larger or take longer to heal.

Pressure ulcers, or bedsores, are a specific type of chronic wound. They result from chronic pressure applied to the skin over a long period. These can form in as little as two hours of immobility. This is a high risk for patients who are unconscious or sedated. In the United States, the National Pressure Injury Advisory Panel (NPIAP) grades these ulcers. Stage 1 involves intact skin with redness, known as erythema. Stage 4 is the most severe, involving damage through subcutaneous tissue down to muscle, tendon, or bone.

Healthcare providers also classify wounds by their level of sterility. The CDC uses a Surgical Wound Classification System for this. Class 1 wounds are clean, meaning they are not infected and show no inflammation. Class 2 wounds are clean-contaminated and involve low levels of contamination. Class 3 wounds are considered contaminated, such as accidental trauma wounds. Class 4 wounds are dirty or infected, often showing signs of devitalized tissue.

A Surgeon Applying a Suture
A Surgeon Applying a Suture

When examining a wound, doctors look at several specific factors. They measure the size of the wound and note its exact location. They also inspect the wound bed. A healthy wound bed should appear pink due to healthy granulation tissue. They must also look for necrotic tissue, which is dead tissue. This can appear as yellow slough or black, hardened eschar. Removing this tissue is vital for healing. Doctors may also use plain radiography, or X-rays, to check for hidden bone fractures.

Xraymachine
Xraymachine

Many different systems exist to classify complex injuries, especially fractures. The Tscherne classification describes the external appearance of wounds in fractures. The Gustilo-Anderson classification is used for open fractures based on tissue loss and contamination. For extremity salvage, doctors may use the Hannover Fracture scale. Finally, the AO classification provides grading for skin, muscles, and neurovascular structures. Understanding these specific details allows for better medical management of every injury.

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File:A skateborder falls off his board and cuts his hand.jpg
A skateborder falls off his board and...
File:Xraymachine.JPG
Xraymachine.JPG
File:wound sewed.jpg
wound sewed.jpg
File:A Surgeon Applying a Suture.jpg
A Surgeon Applying a Suture.jpg
File:Treatment of wound with lance grit.jpg
Treatment of wound with lance grit.jpg
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