1. Homeostatic Imbalances
The Skin
Homeostatic Imbalances

2. Tattoos Needle is used to deposit pigment within the dermis Risks:
One ugly tattoo
Dyes w/cancer causing agents
Hepatitis C
Removal:
Dermabrasion, cryosurgery, caustic chemicals, laser based technology

3. Excessive Sun exposure
Damages skin
Elastic fibers clump -> leathery skin
Chance for herpes (aka cold sore) increases
Alter DNA of skin cells -> skin cancer
inc melanin in black ppl dec chance for skin cancer

4. Decubitus Ulcer Restriction of normal blood supply to skin
Causes cell death
Occurs often in bedridden patients who are no turned regularly or who are dragged or pulled repeatedly across bed
Blood supply restricted -> blanching
Skin reddens when pressure released
Cracks appear in compressed
areas

5. Infections and Allergies
Athlete’s Foot
Itchy, red, peeling
between toes
Fungal infection: fungus grows on or in the top layer of the skin
Easily transferred
Can be caught walking near swimming pools and lockers

6. Infections and Allergies
Boils and carbuncles
Boils: inflammation of hair follicles and sebaceous glands
Carbuncles: boils caused by bacterial infection

7. Infections and Allergies
Cold Sores
Small, fluid-filled blisters
Itch and sting
Caused by herpes simplex infection
Virus localizes in cutaneous nerve
Dormant until activated by emotional upset, fever, or UV

8. Infections and Allergies
Contact dermatitis
Itching, redness, swelling of skin, blistering
Caused by exposure of skin to chemicals
i.e. poison ivy

9. Infections and Allergies
Impetigo
Pink, water-filled, raised lesions
Develops yellow crust and ruptures
Caused by staphylococcus infection
Common in elementary children

10. Infections and Allergies
Psoriasis
Reddened epidermal lesion
Dry, silvery scales
May be disfiguring

11. Burns
Tissue damage and cell death caused by intense heat, electricity, UV, or chemicals
Two life-threatening problems:
Body loses supply of fluids containing proteins and electrolytes
Dehydration and electrolyte loss = shutdown of kidneys and circulatory shock
Lost fluids must be replaced immediately!

12. Burns Rule of nines: Infection leading cause of death in burn victims
Divides body into 11 area, each accounting for 9% of total body surface (plus 1% for genital)
Infection leading cause of death in burn victims
Burned skin sterile for 24 hours
Patient’s immune system depressed

13. Burns First degree Only epidermis damaged Area red and swollen
Not serious
Heals in two to three days
i.e. sunburn

14. Burns
Second degree
Injury to epidermis and upper dermis
Red, painful, and blisters present
Enough epithelial present for regeneration
No permanent scars result if taken care of
First and second degree burns are called partial-thickness burns

15. Burns Third degree Destroys entire thickness of skin
aka full-thickness burn
Burned area is blanched or blackened
Nerve endings destroyed = no pain
Regeneration not painful
Skin grafting

16. Fourth Degree Burn
a burn that extends deeply into the subcutaneous tissue, completely destroying the skin, subcutaneous tendons, underlying tendons, involving muscle, fascia, or bone

17. Burns Considered critical if: 25% has second degree burns
10% has third degree burns
Third degree burns of face, hands, or feet
Dangerous because burned respiratory passageways
Swells and causes suffocation

19. Skin Cancer Single most common type of cancer in humans
Most important risk factor is UV radiation

20. Skin Cancer Basal cell carcinoma Least malignant
Most common type (usu. On face)
Cells in stratum basale cannot form keratin and no longer honors boundary between epidermis and dermis
Appears shiny, dome-shaped nodules that develop an ulcer
Slow-growing
curable

21. Skin Cancer Squamous Cell Carcinoma
Lesion appears scaly, reddened papules
Gradually forms ulcer
Usu on scalp, ears, dorsum of hands, lower lip
Grows rapidly and into lymph nodes if not removed
Curable surgically or w/radiation therapy

22. Skin Cancer Malignant melanoma Cancer of melanocytes
Accounts for 5% of skin cancers
Usu. Appears as spreading brown to black patch
Grows into lymph and blood vessels
Survival is 50%
Treatment is wide surgical excision with immunotherapy

23. Malignant melanoma
Use ABCD on new moles or pigmented spots to recognize
Asymmetry: two sides of spot do not match
Border irregularity: borders of lesion are not smooth and have indentations
Color: spot contains areas of different colors
Diameter: spot is larger than 6 mm in diameter

24. AGE Newborn: skin is thin and blood vessels are visible
Skin thickens with age
Adolescence: skin and hair become oily
Adulthood (twenties and thirties): skin reaches optimal appearance
Environmental affects: abrasion, chemicals, wind, sun, and other irritants clog pores with pollutants and bacteria
dermatitis (skin inflammation), pimples, scales occur

25. FRECKLES: Concentration of Melanin in a certain area
Old Age: subcutaneous tissue decreases, skin is drier, skin thins, decreased elasticity
FRECKLES: Concentration of Melanin in a certain area
HAIR:
By 50, # of follicles dec by 1/3
Bald men have hair in “bald areas”
degenerated follicles develop colorless and tiny hair
Graying: dec in amount of melanin deposited in the hair
emotional crisis, anxiety, protein deficiency, chemotherapy, radiation, excessive vitamin A, fungal diseases, genetics