Chapter 14: Hair Skin Nails
Function of the skin:
Physical barrier that protects the underlying tissues and organs from microorganisms,
physical trauma, ultraviolent radiation, and dehydration
Vital role in temperature maintenance, fluid and electrolyte balance, absorption,
excretion, sensation, immunity, vitamin D synthesis, protection from environment, prevents
penetration, perception, identification, communication, wound repair
Epidermis:
o Outer layer 4 layers
o Stratum corneum, stratum lucidum, stratum granulosum, stratum germinativum
(undergoes cell division and contains melanin)
o Basal cell layer forms new skin cells
o Outer horny cell layer of dead keratinized cells (derivation of skin color)
Dermis
o Inner layer
o Dermal papillae connect dermis to the epidermis
o Fingerprints
o Well-vascularized, connective tissue layer containing collagen, elastic fibers,
nerve endings, and lymph vessels
o Sebaceous gland: attached to hair follicles and present all over body except for
soles and palms
- Secrete oily substance called sebum that waterproofs the hair and skin
o Sweat glands:
- Important for fluid balance and thermoregulation
- Eccrine: located all over skin and function to secrete sweat and
thermoregulation
, - Apocrine: associate with hair follicles. Small and nonfunctional until puberty.
Secrete milky sweat and combined with bacteria create body odor
Subcutaneous tissue
o Loose connective tissue containing fat cells, blood vessels, nerves, and the
remaining portions of the sweat glands and hair follicle
o Stores fat as energy reserve
o Provides insulation
o Serves as a cushion to protect bones and internal organs
o Contains vascular pathways for the supply of nutrients and removal of waste
products to and from the skin
Functions of hair
Vellus: peach fuzz, short, pale, fine, and present over most of the body
o Provides thermal regulation by wicking sweat from the body
Terminal: particularly scalp and eyebrows, longer, darker, and coarser
o Protect scalp
o Provide insulation
Function of nails
Nail protects the distal ends of the fingers and toes
Enhance precise movement of digits
Allow for an extended precision grip
, ASSESSMNET:
SKIN INSPECTION
Inspect general coloration
o Individuals with fair skin are at an increased risk for skin cancer
o Small amounts of melanin are common in pair people while larger amounts are
common in olive and darker skins. Carotene accounts for yellow cast.
o Older adults skin become pale due to decreased melanin production and decreased
dermal activity
Normal Abnormal
Evenly colored skin Pallor (loss of color) is seen in arterial insufficiency, decreased
blood supply, and anemia. Vary from pale to ashen
Cyanosis may cause skin to appear blue-tinged, especially in
perioral, nail bed, and conjunctival areas
Dark skin may appear blue, dull, and lifeless
Central cyanosis results from a cardiopulmonary problem
Peripheral cyanosis may be local resulting from
vasoconstriction
TO DIFFERENTIATE, LOOK FOR CENTRAL
CYANOSIS IN THE ORAL MUCOSA
Jaundice is yellow skin tones, ranging from pale to pumpkin
Seen in sclera, oral mucosa, palms, and soles
Acanthosis nigricans: velvety darkening of skin in body folds
and creases, especially the neck, groin, and axilla
While expecting skin color, note any odors
Normal Abnormal
Slight or no odor of Strong odor of perspiration or foul odor may indicate
perspiration disorder of sweat glands
Poor hygiene may indicate need for client teaching or
assistance of daily living
Asians and Native Americans have mild to no odor
Caucasians and AA tend to have strong body odor
Inspect for color variation
o Pale or light skinned clients have darker pigmented nipples, lips, and genitalia
o SLE prevalence is higher in Asians, Afro-Americans, Afro-Caribbean's, and
Hispanics in the US but infrequent in blacks in Africa.