Wound Management and Healing

Wound Management

• Wound is defined as a break or disruption in the normal integrity of skin and tissues.

Learning Objectives

• Define wound
• Describe different types of wounds
• Describe the physiology of wound healing
• Identify factors affecting wound healing
• Outline wound complications
• Describe wound management
• Health educate patients on wound healing promotion

Types of Wounds

• Incision: Cutting or sharp instrument; wound edges are close to each other and aligned.
• Contusion: Blunt instrument; overlying skin remains intact; injury to underlying soft tissue; possible bruising, and/or hematoma.
• Abrasion: Friction; rubbing or scraping epidermal layers of skin; top layer of skin is abraded.
• Laceration: Tearing of skin and tissue with blunt or irregular instrument. Tissue is not aligned; often with loose flaps of skin and tissue.
• Puncture: Blunt or sharp instrument puncturing the skin; intentional (e.g., venipuncture), or accidental.
• Penetrating: Foreign object entering the skin or mucous membrane and lodging in underlying tissue. Fragments may scatter.
• Burns: (thermal, chemical, irradiation) destroy the layers of skin.
• Pressure ulcers: Compromised circulation secondary to pressure or pressure combined with friction.

Classifications of Wounds

• Clean: Non-traumatic site, uninfected, no inflammation, no break in aseptic technique.

• Clean-contaminated: Entry into respiratory, alimentary, genitourinary, or oropharyngeal tracts without unusual contamination. Minor break in aseptic technique; mechanical drainage.

• Contaminated: Open, newly experienced traumatic wounds. Gross spillage from gastrointestinal tract. Major break in aseptic technique; entry into genitourinary or biliary tract when urine or bile is infected.

• Dirty: Traumatic wound with delayed repair, devitalized tissue, foreign bodies, or fecal contamination. Acute inflammation and purulent drainage.

Physiology of Wound Healing

• Wound healing is a tissue response to injury.
• Mechanisms repair injured tissue by regenerating functioning cells and replacing connective tissue with scar tissue.
• Wound healing has phases.

Phases of Wound Healing

Phase 1: Hemostasis

• Occurs immediately after injury.
• Involved blood vessels constrict.
• Blood clotting begins through platelet activation and clustering.
• Blood vessels dilate after constriction.
• Increased capillary permeability allows plasma and blood components to leak out; forming exudate (liquid).
• Accumulation of exudates causes swelling, pain, increased perfusion results in heat and redness.
• Blood clot forms (hard scab) to protect the injury.
• Platelets release substances that stimulate other cells to participate in healing.

Phase 2: Inflammatory Phase

• Follows hemostasis.
• Lasts about 4-6 days.
• White blood cells move to the wound.
• Leukocytes arrive to ingest bacteria and cellular debris.
• Macrophages enter the wound area, about 24 hours after injury, and remain for an extended period.
• Macrophages ingest debris and release growth factors for epithelial cells and new blood vessels.
• Growth factors attract fibroblasts, which help fill in the wound.
• Acute inflammation characterized by pain, heat, redness, and swelling.
• Patient experience generalized body response; including mildly elevated temperature, leukocytosis (increased white blood cells), and generalized malaise.

Phase 3: Proliferative Phase

• Known as the fibroblastic or regenerative phase.
• Tissue formation to fill the wound gap.
• Primarily occurs through fibroblasts.
• Capillaries grow across the wound, providing oxygen and nutrients for continued healing.
• Fibroblasts form fibrin that stretches through the clot.
• Thin layer of epithelial cells forms across the wound.
• Blood flow resumes (reinstituted) across the wound.
• Granulation tissue formation (basis for scar tissue).
• Highly vascular, red, easily bleeds.
• Collagen synthesis and accumulation peak in 5-7 days.
• Collagen deposit continues for weeks or years depending on the wound size.
• Majority of white blood cells leave the wound area towards the end of the second week.
• Wound lighter in color (wound area).

Phase 4: Maturation Phase

• The final stage of healing.
• Begins about 3 weeks after injury.
• Continues for months or years.
• Collagen that was haphazardly deposited is remodeled for a stronger wound; like adjacent tissue.
• New collagen continuously deposited, which compresses blood vessels (in the healing wound).
• Scar (avascular collagen tissue) becomes flat and thin and does not sweat, grow hair, or tan.
• Scar tissue is strong but less elastic than uninjured tissue.

Factors Affecting Wound Healing

• Local Factors:

  • Pressure disrupts blood supply; interferes with blood flow to the tissue; delays healing.
  • Desiccation (drying up): cells dehydrate and die in a dry environment; causes crusting; delays healing.
  • Maceration (overhydration of cells): occurs due to moisture, pH of skin changes, overgrowth of bacteria and infection, and skin erosion from friction on moist skin.

• Systemic factors:

  • Age: Children and healthy adults heal faster; older adults have slowed fibroblastic activity and circulation, and more chronic illnesses; impede the healing process.
  • Circulation and Oxygenation: Adequate blood flow is needed to deliver nutrients and oxygen; and to remove toxins, bacteria, and debris. Certain conditions (obesity) can affect the outcome of healing due to fat tissue hindering healing and elevating infection risk.
  • Nutritional status: adequate proteins, carbohydrates, fats, vitamins (A & C), minerals, and calories essential for rebuilding cells. Zinc plays a role in proliferation. Poor nutrition and fluid balance can negatively affect wound healing.

• Other factors: - Trauma: Repeated trauma to a wound area results in delayed healing.

    - Edema: Edema at a wound site interferes with blood supply (to the area), resulting in an inadequate supply of oxygen and nutrients.
  
    - Infection:-Infection requires large amounts of energy from immune system to fight microorganisms; leaving little, or no reserve energy to focus on repair.  Toxins from bacteria interfere with wound healing and cell death.
  
    - Necrotic tissue: Presence of necrotic or dead tissue in wound inhibits healing (slough, moist yellow stringy tissue and/or eschar).
  

Wound Complications

• Infection: Bacteria invades wound at time of trauma, surgery, or anytime after.
• Hemorrhage: Bleeding from a slipped suture, a dislodged clot, stress on the suture line, infection, or a blood vessel erosion by a foreign body (e.g., a drain).
• Dehiscence: Partial or total disruption of wound layers.
• Evisceration: Protrusion of viscera (organs) through the incision.
• Fistula formation: Abnormal passage from internal organ to skin, or internal organ to another; often from delayed healing; manifested by drainage; increases risk of infection, fluid, and electrolyte imbalances.

Nursing Management of Wound

• Assessment: Assess wound edges, color, condition (dehiscence or evisceration), drains, tubes, sutures, presence of infection.
• Drainage: Assess amount, color, odor, consistency, using wound, dressing, drainage bottles, or under patient.
• Pain: Pain can increase. Pain accompanied by increased drainage suggest delayed healing or infection.

Educating the Patients on Wound Care

• Keep wound dry and clean (and change dressings when necessary).
• Report any signs of infection (redness, swelling, tenderness, warmth around the wound, pus/discharge, and foul odor).
• Elevate affected part to heart level to reduce swelling.
• Dry cool packs or analgesics/pain medicine for pain.
• Plenty of food rich in protein and vitamin C should be consumed.