SKIN

The Skin: Assessment, Staging, Treatments

Overview of the Skin as an Organ

• The skin is the largest external organ of the body.

• Among its primary roles are:

  • Defending the body as a sensory organ for pain, touch, and temperature.

  • Playing a significant role in thermoregulation, metabolism, immunity, and fluid balance regulation.

  • Proper wound care is essential to promote healing, resulting in intact skin layers.

  • Nurses are responsible for performing ongoing assessments of patients and their wounds.

Structure of the Skin

• The skin consists of three primary layers:

  • Epidermis

  • Dermis

    • Contains collagen, blood vessels, and nerves.

  • Hypodermis (subcutaneous layer)

• Important junction between epidermis and dermis is the dermoepidermal junction, also known as the basement membrane zone.

Wound Assessment

• Wound assessments should be conducted on a scheduled basis to check for:

  • Progress towards healing in accordance with institutional standards.

  • Types and phases of wound healing:

  • Homeostasis

  • Inflammatory

  • Proliferative

  • Maturation

Phases of Wound Healing

1. Homeostasis: Initial response to injury, stopping the bleeding.

2. Inflammatory Phase: Body's response to the initial injury; includes redness and warmth as blood vessels dilate.

3. Proliferative Phase: Characterized by fibroblast activity and new tissue formation.

4. Maturation Phase: Remodeling of collagen and restoration of original skin strength.

Types of Wound Healing Intention

• Primary Intention:

  • Tissues approximated by surgical sutures or tapes with minimal tissue loss.

  • Resulting in a clean, thin scar.

• Secondary Intention:

  • Extensive loss of cells or larger surface wounds create more complex reparative processes.

  • Granulation tissue grows in from the margins.

  • Wounds heal with a larger, often more noticeable scar.

• Tertiary Intention:

  • Delayed primary wound healing occurring after 4-6 days.

  • Involves interrupting the secondary intention process and mechanically closing the wound.

  • Example includes the use of a negative pressure wound therapy device.

Factors Affecting Wound Healing

• Primary Factors:

  • Hypoxia: Lack of oxygen to tissues.

  • Bacterial Colonization: Presence of bacteria inhibiting healing.

  • Ischemia: Reduced blood flow to tissues.

  • Reperfusion Injury: Damage caused when blood supply returns to tissue after a period of ischemia.

  • Altered Cellular Response: Changes in cellular activities due to various factors.

  • Collagen Synthesis Defects: Problems in collagen production affecting skin integrity.

• Systemic Factors:

  • Conditions like diabetes, chronic illness, smoking, and malnutrition that can impair healing.

• Local Factors:

  • Issues such as pressure, tissue edema, infection, maceration, and dehydration.

Types of Wounds and Healing Areas

• Types of wounds based on depth:

  • Partial-thickness wounds

  • Full-thickness wounds

• Negative-pressure therapy:

  • Macro deformation and micro deformation respond to pressure differences in the wound.

Assessment Tools

The Braden Scale for Predicting Pressure Ulcer Risk

• Comprises six subscales scored based on patient risk:

  1. Sensory Perception: 1-4 scale

     • 1: Completely limited

     • 2: Very limited

     • 3: Slightly limited

     • 4: No impairment

  2. Activity: 1-4 scale

     • 1: Bedfast

     • 2: Chairfast

     • 3: Walks occasionally

     • 4: Walks frequently

  3. Mobility: 1-4 scale

     • 1: Completely immobile

     • 2: Very limited

     • 3: Slightly limited

     • 4: No limitation

  4. Moisture: 1-4 scale

     • 1: Constantly moist

     • 2: Very moist

     • 3: Moist occasionally

     • 4: No impairment

  5. Nutrition: 1-4 scale

     • 1: Very poor

     • 2: Probably inadequate

     • 3: Adequate

     • 4: Excellent

  6. Friction and Shear: 1-3 scale

     • 1: Problem

     • 2: Potential problem

     • 3: No apparent problem

• Braden Scale Classifications:

  • Low risk: Scores 19-23

  • Moderate risk: Scores 13-18

  • High risk: Scores 10-12

  • Severe risk: Scores <9

Contributing Factors to Pressure Injury

• Pressure: Compression of tissue between two surfaces.

• Friction: Force generated when two surfaces move against each other.

• Shear: Tissue stretching in opposing directions.

• Excessive Moisture: Weakens skin, increasing likelihood of breakdown.

• Decreased Activity/Mobility: Limits blood circulation to tissues.

• Tissue Tolerance: Affected by factors like age, nutrition, and glycemic control.

• Medical Conditions: Vascular, neurological, pulmonary, or immunocompromised states may hinder healing.

Pressure Injury Definitions

• Pressure Injury: Localized damage to the skin and/or underlying tissue usually over bony prominences due to pressure, shear, and/or friction.

Pressure Ulcer Categories

• Stage I:

  • Intact skin with non-blanchable redness over a bony prominence.

  • Darkly pigmented skin may show color differences without blanching.

  • Area may feel painful, firm, or cooler compared to surrounding tissue.

• Stage II:

  • Partial thickness loss of dermis presenting as a shallow open ulcer with a red-pink wound bed.

  • May appear as a serum-filled blister.

  • Should not be confused with skin tears or burns.

• Stage III:

  • Full thickness tissue loss with visible subcutaneous fat.

  • Bone, tendon, or muscle are not exposed but may have slough or undermining.

• Stage IV:

  • Full thickness skin and tissue loss exposing fascia, muscle, tendon, or cartilage.

  • Characterized by epibole, undermining, and tunneling.

• Unstageable:

  • Full thickness loss where the base of the ulcer is covered by slough or eschar, preventing depth determination.

  • Stable eschar on heels should not be removed.

Important Considerations for Wound Care

• Cleansing wounds and removing nonviable tissue are critical steps.

• Prevent and manage infections and maintain appropriate moisture levels.

• Document aspects like staging, color, drainage, amount, and any signs of pain adequately.

• Assess not only the wound, but surrounding tissue, including lips and nose for integrity and potential injury.

Key Principles of Wound Care

1. Cleanse wound thoroughly.

2. Remove any nonviable or devitalized tissue.

3. Prevent infections and manage existing ones effectively.

4. Maintain suitable moisture levels for healing.

5. Eliminate dead space in the wound bed.

6. Protect the wound and peri-wound skin.

7. Control odors emanating from the wound.

8. Alleviate pain associated with wound healing.

9. Address any contributing factors, such as poor nutrition or oxygen levels.

Removal of Sutures and Staples

• Sutures and staples are typically removed within:

  • 7 to 14 days for standard wounds.

  • 14 to 21 days for retention sutures used in larger abdominal wounds.