- Outermost layer
- Loosely woven fibers in gelatinous matrix called ground substance
- Blisters occur here if friction
- Collagen and reticular fibers
- ---Important in healing wounds
- Innermost layer
- Connective tissue that provides increased structural support to the skin
- Collagen that anchors it to subcutaneous tissue, fascia, muscle, and bone
- Supports and nourishes epidermis
- infection control
- Houses epidermal appendages – Hair, Glands, Nails
- Layer of loose connective tissue
- High proportion of fat cells
- Insulates body
- Absorbs shock
Functions of Skin
- 1 Protection of internal structures
- 2 Sensory perception (nerve cells inside)
- 3 Thermoregulation
- 4 Excretion
- 5 Metabolism
- 6 Absorption
- 7 Social communication
- 50% reduction cell turnover rate
- 20% reduction in dermal thickness
- Reduction in dermal vasculature
- Redistribution of subcutaneous tissue
- Decreased number of Langerhan’s cells
- 50% decrease in fibroblast and mast cells
- Decreased sensation
- Decreased # sweat glands
- Decreased absorption through the skin
- Decreased ability to synthesize vitamin D
Ramifications for Elderly patients
- Pressure and thermal damage
- Shears and tears
- Hyper and hypothermia
- Types of wound healing
- Primary intention
- Secondary intention
- Tertiary intention
- Involves reepithelialization.
- Mostly superficial wounds involving the epidermis or wound with clean edges pulled tightly together like a surgical wound.
- Heal in 4 – 14 days and result in minimal scarring.
- Wound that involves tissue loss - EG, pressure ulcers, burns, surgical dehisced wounds, traumatic injury
- Edges can’t be easily approximated. Healing occurs by wound repair.
- Classified as: *****
- ---Partial thickness
- ---Full thickness.
- During healing, wound will fill with granulation tissue, scar forms, and reepithelialization occurs primarily from the wound edges.
- Longer to heal, more complications
- Wound deliberately left open to allow edema or infection to resolve or permit removal of exudate.
- After this period, wound is closed by surgeon
- More scarring than primary intention wounds, but less scarring than secondary intention wounds.
- Phases overlap
- 1. Inflammation
- 2. Proliferation
- 3. Maturation/remodeling
- ***Occurs immediately, 2-5 days in healthy individuals.
- vasoconstriction and platelet plug to stop flow of blood
- WBC kill bacteria nad damaged tissue
- Mast cells produce histamine for inflammation to bring more chemical mediators here
- 2 days to 3 weeks depending on size
- Granulation tissue formation
- Wound contraction
- Collagen synthesis continues at a rapid rate after wound closure.
- The wound is strengthened and reorganized to fit the surrounding tissue.
- Remodeling continues up to 2 years with the greatest amount of change in the first 6 months to one year.
- Wounds usually have only 80% of the skin’s original tensile strength.