Engage Fundamentals - Tissue Integrity

Definition: Tissue integrity refers to the ability of the human body to regenerate and maintain normal physiological functioning.
Defense Mechanisms: The body utilizes skin, cornea, subcutaneous tissue, and mucous membranes as barriers to protect against various external threats such as injury, infection, and environmental factors.

Largest Organ System:
- Comprises about 15% of total body weight.
Main Functions:
- Protection: Acts as a barrier against injury, infection, ultraviolet (UV) radiation, and heat.
- Sensory Perception: Vital for sensations such as touch, pain, pressure, and vibration.
- Temperature Regulation: Maintains and adjusts body temperature in response to changes in environmental conditions.
- Waste Elimination: Assists in the excretion of waste products.
- Vitamin Synthesis: Facilitates the production of Vitamin D.

Epidermis:
- The outermost layer composed primarily of keratinocytes and includes additional cell types like melanocytes, Merkel cells, and Langerhans cells.
Dermis:
- The largest portion of the skin, providing strength and flexibility.
- Composed of connective tissue with various structures such as:
  - Capillaries
  - Blood vessels
  - Lymph vessels
  - Nerves
  - Sweat and sebaceous glands
  - Hair roots
  - Elastic fibers
  - Collagen
Subcutaneous Tissue:
- Composed of subcutaneous fat (adipose tissue).
- Functions include:
  - Insulation
  - Shock absorption
  - Protective padding for internal organs and structures

Definition: Skin frailty refers to skin that is at risk or vulnerable.
Risk Factors:
- Aging
- Mobility Issues
- Body Weight
- Chronic Conditions:
- Spina bifida
- Cerebral palsy
- Liver and renal diseases
- Cancer
- Malnutrition

As adults age, skin undergoes several changes:
- Thinning of skin
- Loss of elasticity
- Reduction of subcutaneous fat
- Decreased blood supply
- Lower hydration levels
Consequence: Increased susceptibility to shear, friction, and pressure injuries.

Definition: Also known as bedsores or pressure ulcers, these are localized damage to the skin and/or underlying tissue caused by sustained pressure or pressure combined with shear forces.
Common Locations: Often occur over bony prominences such as:
- Heels
- Toes
- Sacrum
- Hips
- Elbows
- Shoulders
- Back of the head
Causes: Can also arise from medical devices like urinary catheters and oxygen tubing.

Assessment: Classified according to the extent of tissue loss observed in the wound, typically using a scale of 1-4.

Stage 1: Nonblanchable erythema of intact skin.
Stage 2: Partial-thickness skin loss with exposed dermis.
Stage 3: Full-thickness skin loss.
Stage 4: Full-thickness skin and tissue loss.
Unstageable: Obscured full-thickness skin and tissue loss.
Deep Tissue Pressure Injury (DTPI): Persistent nonblanchable deep red, maroon, or purple discoloration.

The TIME mnemonic serves as a guide for documenting pressure injuries:
- T tissue integrity: Describe the appearance of tissue, including color and presence of necrotic tissue.
- I inflammation or infection: Note signs of infection such as redness, warmth, swelling, and discharge.
- M moisture: Document the level of moisture or dryness, and if maceration is present.
- E edge of wound: Describe the characteristics of the wound edge.

Hemostatic or Inflammatory Phase:
- Damaged tissue releases cytokines, triggering hemostasis.
- Blood coagulation occurs, initiating wound healing, with plasma leakage causing swelling.
Proliferative Phase:
- Formation of new collagen fibers, creation of a new wound bed, and growth of new capillaries.
- Wound edges begin to close as granulation tissue develops.
Remodeling Phase:
- Replacement of soft gelatinous collagen with stronger collagen; however, this new tissue remains weaker than original tissue and is at increased risk for re-injury.

Primary Healing (First Intention):
- Typically occurs in clean cuts and surgical incisions, closed with skin adhesives or sutures.
Secondary Healing (Second Intention):
- Wound healing occurs naturally without closure, allowing the wound to heal from the bottom up.
Delayed Primary Closure:
- A hybrid method where the wound is left open for 5-10 days before being closed.

Blanchable vs. Non-blanchable Erythema:
- Non-blanchable erythema signifies redness that persists under pressure, indicating structural damage to skin has occurred.

Measurement Methods: Two common methods for measuring wound size include:
1. Tracing the wound circumference and using transparent tape to calculate surface area.
2. Measuring length and width directly.
Importance: Consistency in measurement methods is vital for accurately tracking wound healing progress.

Classification Based on Healing:
- Acute Wounds: Developed due to trauma, healing typically occurs normally over time.
- Chronic Wounds: Result from acute wounds that fail to progress in healing over time.

Definition: The process of removing accumulated debris (biofilm) and dead tissue from a wound using surgical instruments.
Purpose: Reduces bacterial load and stimulates wound bed remodeling.

Types of Dressings: Available dressings can be classified into wet or dry based on the needs of the wound base, healing rate, and level of exudate.

Major Complications: Include:
- Infections: Microbial invasion leading to systemic complications.
- Dehiscence: Partial or total separation of tissue layers.
- Eviscerations: Protrusion of internal organs through wound gaps.
- Hematomas/Seromas: Accumulation of blood or fluid post-surgery.
- Fistulas: Abnormal connections between two epithelial surfaces.