Skin Anatomy and Wound Classification

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Questions and Answers

What is the definition of a wound?

A break in the integrity of the skin or tissues (correct)

A surface scratch without tissue damage

A type of therapy for skin regeneration

An infection that occurs on the skin

Which type of wound is considered an intentional wound?

Hematoma

Surgical incision for hernioplasty (correct)

Lacerated wound

Contusion

Which wound classification is described as having an infective rate of less than 2%?

Contaminated wound

Clean wound (correct)

Clean contaminated wound

Dirty wound

What type of closed wound is characterized by swelling due to blood collection?

Contusion Signup and view all the answers

Which type of wound would be considered contaminated?

A wound with purulent drainage Signup and view all the answers

What is the characteristic of a clean contaminated wound?

Controlled entry into colonized body cavities Signup and view all the answers

What distinguishes an avulsion from other types of wounds?

It involves a tearing away of skin or tissue Signup and view all the answers

Which of the following wounds involves a break in the skin with loss of integrity?

Open wound Signup and view all the answers

What type of wound involves loss of the entire epidermis and part of the dermis?

Partial thickness wound Signup and view all the answers

Which type of wound is characterized by staying open for an expected healing period?

Chronic wound Signup and view all the answers

During which phase of wound healing does the formation of a fibrin plug occur?

Hemostasis phase Signup and view all the answers

Which component is primarily responsible for the infiltration during the inflammatory phase?

Neutrophils Signup and view all the answers

What is the average duration of the inflammatory phase of wound healing?

72 hours Signup and view all the answers

What process begins around the third day post-injury and can last for 3 to 6 weeks?

Proliferative phase Signup and view all the answers

Which phase of wound healing focuses on tissue remodeling and maturation?

Maturation phase Signup and view all the answers

Which of the following is NOT a characteristic of acute wounds?

Healing duration exceeds 4 weeks Signup and view all the answers

What effect does hypoxia have on fibroblast activity?

Inhibits fibroblast proliferation Signup and view all the answers

Which vitamin deficiency impairs collagen synthesis?

Vitamin C Signup and view all the answers

What is the primary role of zinc in wound healing?

Serving as a cofactor for DNA polymerase Signup and view all the answers

How does obesity affect wound healing?

Reduces microcirculation Signup and view all the answers

What is one effect of corticosteroids on the wound healing process?

Inhibit angiogenesis Signup and view all the answers

Which drainage type is noted for its clear, straw-colored fluid?

Serous Signup and view all the answers

What role does vitamin K play in the body relevant to wound healing?

Synthesizes coagulation factors Signup and view all the answers

Which factor contributes to wound assessment?

Presence of foreign body Signup and view all the answers

What type of collagen is remodeled to increase wound tensile strength?

Collagen type III Signup and view all the answers

What is a characteristic of scar tissue in the maturation phase?

It regains 80% of strength. Signup and view all the answers

Which of the following is not a type of wound healing?

Quaternary healing Signup and view all the answers

Which systemic factor can negatively affect wound healing?

Obesity Signup and view all the answers

What complication occurs when a wound opens up after it has started to heal?

Wound dehiscence Signup and view all the answers

How does smoking impact wound healing?

Interferes with oxygen supply Signup and view all the answers

Which nutritional deficiency can impede wound healing?

Vitamin C Signup and view all the answers

What is the primary consequence of infection during the wound healing process?

Prolonged inflammatory phase Signup and view all the answers

Study Notes

Skin Anatomy

Skin is the body's largest organ and acts as a barrier against the environment.
It's composed of three layers: epidermis, dermis, and subcutaneous fat.

Definition of Wound

A wound is a break in the skin or tissue integrity that disrupts structure and function.

Wound Classifications

Based on Cause of Wound

Intentional wounds: Result from planned medical procedures (e.g., surgery).
Unintentional wounds: Result from unexpected events (e.g., accidents, injuries).

Based on Skin Integrity Status

Open wounds: Visible breaks in the skin's surface.
Closed wounds: Damage beneath the skin without breaking the surface (e.g., contusions, hematomas).

Types of Closed Wounds

Contusion/ Bruise: Caused by blunt force trauma, resulting in localized bleeding under the skin.
Abrasion: Superficial scrapes or scratches.
Hematoma: Collection of blood under the skin, often from a deep bruise or puncture.

Types of Open Wounds

Incised Wound: Clean-cut wound from a sharp object (e.g., knife).
Lacerated Wound: Jagged tear caused by blunt force trauma.
Avulsion: Tearing away of a flap of skin or tissue.
Penetrating Wound: A wound that perforates through the skin and underlying tissues (e.g., gunshot, stab wound).

Based on Wound Cleanliness (Berard Wound Classification)

Clean Wound: Elective, primarily closed surgical wounds with no entrance of normally colonized body cavities.
Clean-Contaminated Wound: Controlled opening of normally colonized body cavities; minimal risk of infection.
Contaminated Wound: Acute inflammation, open trauma, or breach of sterile technique within 4 hours of injury.
Dirty/ Infected Wound: Purulent abscess, traumatic wounds with retained dead tissue, or wounds with ongoing infection.

Based on Skin Thickness Loss

Superficial Epidermal Wounds: Impact the outer layer of skin but not deeper tissues.
Partial-Thickness Wounds: Extend through the epidermis into the dermis.
Full-Thickness Wounds: Involve all skin layers, potentially down to subcutaneous fat, muscle, or bone.

Based on Time Elapsed/ Wound Duration

Acute Wounds: Show signs of healing within four weeks.
Chronic Wounds: Fail to heal within an expected timeframe based on their type and location.

Physiology of Wound Healing

A complex process that restores anatomical and functional integrity to damaged tissue.
Involves various cells (e.g., neutrophils, macrophages, fibroblasts) and components (e.g., collagen) working together.
Occurs in four overlapping phases: hemostasis, inflammation, proliferation, and remodeling.

Hemostasis Phase (Seconds to Minutes)

Constriction of blood vessels.
Formation of a temporary "platelet plug" to stop bleeding.
Activation of the coagulation cascade.
Formation of the final blood clot (fibrin plug).

Inflammatory Phase (Lasts for 72 Hours)

Mast cells release substances like histamine that trigger inflammation.
Neutrophils (white blood cells) arrive and fight infection.
Monocytes migrate and differentiate into macrophages to clean debris.
Cytokines and growth factors released by these cells stimulate fibroblasts and epithelial cells.

Proliferative Phase (Days 3 to 3-6 Weeks)

Granulation Tissue Formation: New blood vessels and connective tissue form.
Extracellular Matrix & Collagen Synthesis: Fibroblasts produce collagen to provide strength and support.
Angiogenesis: New blood vessels grow to supply the healing tissue.
Re-epithelialization: Skin cells migrate to re-cover the wound surface.

Remodeling/ Maturation Phase (6 Weeks to 1-2 Years)

Collagen fibers remodel and reorganize for increased strength.
Collagen type III transitions to collagen type I, making the scar stronger.
Blood vessels mature and decrease in number.
Scar tissue regains approximately 80% of its original tissue strength.

Types of Wound Healing

Primary Healing (First Intention): Wounds that are closed immediately, typically with sutures, allowing for minimal scar formation.
Secondary Healing (Second Intention): Wounds left open to heal from the bottom up, resulting in more scar tissue.
Tertiary Healing (Delayed Primary Closure): Wounds initially left open and then closed later after debridement and infection control are achieved.

Complications of Wound Healing

Infection: Bacteria enter the wound and multiply, hindering healing.
Hemorrhage: Bleeding from the wound site, potentially leading to blood loss and shock.
Fistula: An abnormal connection between two body surfaces (e.g., between a wound and the intestine).
Wound Dehiscence: Partial or complete opening of the wound edges along the suture line before healing is complete.
Wound Evisceration: Protrusion of internal organs through a dehisced wound.

Factors Affecting Wound Healing

Local Factors

Infection: Presence of bacteria delays healing.
Necrotic Tissue & Foreign Bodies: Dead tissue and foreign objects impede healing processes.
Tissue Hypoxia: Reduced oxygen supply hampers macrophage and fibroblast activity.
Venous or Lymph Stasis: Slowed blood or lymph drainage leads to poor nutrient delivery and waste removal.
Recurrent Trauma: Repeated injury to the healing wound delays healing.

Systemic Factors

Age: Elderly individuals tend to heal more slowly.
Smoking: Reduces oxygen delivery, impairs WBCs, and decreases fibroblast function.
Stress: Suppresses immune responses and wound healing.
Obesity: Increases wound tension, reduces blood supply, and increases risk of complications.
Malnutrition: Inadequate intake of proteins, vitamins, and minerals slows wound repair.
Vitamins and Minerals: Deficiencies in vitamin A, vitamin C, vitamin K, zinc, copper, magnesium, and iron have negative impacts on wound healing.
Metabolic Diseases (E.g., Diabetes): Impair blood sugar control and immune function, affecting healing.
Anemia & Hypoxia: Reduced oxygen supply to tissues hinders wound repair.
Drugs (Steroids, NSAIDs, Chemotherapy): Interfere with various aspects of wound healing.
Immunocompromised Conditions: Weaken the immune system, making infection more likely.

Wound Assessment

Site of Wound: Location and surrounding tissues.
Type of Wound: Incised, lacerated, etc.
Mode of Injury: How the wound occurred.
Foreign Body: Presence of any foreign object.
Severity of Pain & Bleeding: Indicators of the wound's depth and extent of injury.
Wound Length, Width & Depth: Dimensions of the wound.
Tissue Viability: Assessment of the health of tissue surrounding the wound (e.g., color, texture, temperature).
Drainage: Type and amount of fluid draining from the wound (serous, serosanguineous, purulent, sanguineous).
Wound Drains: Presence of drainage tubes to remove fluids.

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Description

Explore the fascinating details of skin anatomy, including its three primary layers and vital functions. Delve into wound classifications based on their causes and skin integrity. Perfect for understanding the fundamentals of skin and wound care.