Subcutaneous
Subcutaneous fat (adipose tissue fat) is the innermost layer of the
skin, lying over muscle and bone. Blood vessels go through the fatty
layer and extend into the dermis, forming capillary networks that
supply nutrients and remove wastes.
Dermis
The dermis (corium) is the layer above the fat layer and contains no
skin cells but does contain some protective mast cells and
macrophages. It is composed of interwoven collagen and elastic fibers
that give the skin flexibility and strength.Collagen is the main
component of dermal tissue and is produced by fibroblast cells. Its
production increases in areas of tissue injury and helps form scar
tissue. Fibroblast also produce ground
substance, a lubricant that contributes to skin
suppleness and turgor. The major component of the elastic fiber in the
dermis is elastin. The dermis has capillaries and lymph vessels for
the exchange of oxygen and heat. It is rich in sensory nerves that
transmit the sensations of touch, pressure, temperature, pain, and itch.
Epidermis
The outermost skin layer. It is anchored to the dermis by
rete pegs that interlock with dermal
structures called dermal papillae.
Less than 1mm thick, the epidermal layer is the first line
of defense between the body and the environment. It does
not have its own blood supply.
Keratinocytes
Skin cells that undergo cell division and differentiation to
continuously renew skin tissue integrity and maintain optimal barrier function.
Stratum Corneum
Outermost horny skin layer. When keratinocytes continue to enlarge
and flatten as they move upward, they reach the stratum corneum in
28-45 days and are no longer living cells, they shed from the skin surface.
Keratin
A protein produced by keratinocytes, makes the horny layer waterproof.
Stratum lucidum
On the palms of the hands and soles of the feet, thick layer of
epidermis. This clear layer of nonliving cells pads and protects the
underlying dermal and epidermal structures in these vulnerable areas.
Melanocytes
Pigment producing cells found at the basement membrane, give color to
skin and account for the ethnic differences in skin tone. Darker skin
tones are not caused by increased numbers of melanocytes; rather, the
size of the pigment granules (melanin) contained in each cell
determines the color. Melanin protects the skin from damage by UV
light. Freckles, birthmarks, and age spots are lesions caused by
patches of increased melanin production.
Lunula
The white, crescent-shaped portion of the nail at the lower end of
the nail plate, and is where nail keratin is formed and nail growth
begins. Fingernail replacement requires 3-4 months. Toenail
replacement may take up to 12 months.
Sebaceous glangs
Distributed over the entire skin surface except for the palms of the
hands and soles of the feet. Most of these glands are connected
directly to the hair follicles. They produce sebum, a
mildly bacteriostatic fat containing substance. Sebum lubricates the
skin and reduces water loss from the skin surface.
Sweat Glands
Eccrine
Arise from the epithelial cells. They are found over the entire skin
surface and are not associated with hair follicles. The odorless,
colorless secretions of these sweat glands are important in body temp
regulation. This sweat and the resultant water evaporation can cause
the body to lose up to 10-12 L of fluid in a single day.
Sweat Glands
Apocrine
Sweat glands are in direct contact with the hair follicle and are
found mostly in the axillae, nipple, umbilical, and perineal body
areas. The interaction of skin bacteria with the secretions of these
glands causes body odor.
Nutritional Status
Document the patients weight, height, body build, and fat
distribution, and food preferences. Protein deficiencies, vitamin
deficiencies, and obesity can increase the risk for skin lesions and
delay wound healing. Fat free diets and chronic alcoholism can lead to
vitamin deficiencies and related skin changes. Skin manifestations of
severe fluid losses are seen as loose skin that tents when pinched
together. Fluid overload with edema can stretch the skin, masking
wrinkles and allowing the formation of skin "pits" when
pressure is applied to it.
Primary Lesions
Initial reaction to a problem that alters skin components.
macules nodules patches
cysts papules plaques vesicles
pustules wheals-insect bites erosions
Secondary Lesions
Changes in the appearance of the primary lesions. These changes occur
with progression of an underlying disease or in response to a topical
or systemic therapeutic intervention. For example, acute dermatitis
often occurs as primary vesicles with associated
pruritus (itching). Secondary lesions in the form of
crusts occur as the patient scratches, the vesicles are opened, and
exudate dries. With chronic dermatitis, the skin often becomes
lichenified (thickened) because of the patient's
continual rubbing of the area to relieve itching.
scales, ulcers, lichenifications, fissures, crusts and
oozing, atrophy
Assess each lesion for these ABCDE features
associated with skin cancer.
A: Asymmetry of shape
B: Border irregularity
C: Color variation within one lesion
D: Diameter greater than 6mm
E: Evolving or changing in any feature (shape,
size, color, elevation, itching, bleeding, or crusting)
annular
ringlike with raised borders around flat, clear centers of normal skin
circinate
circular
circumscribed
well defined with sharp borders
clustered
several lesions grouped together
coalesced
lesions that merge with one another and appear confluent
diffuse
widespread, involving most of the body with intervening areas of
normal skin; generalized
linear
occurring in a straight line
serpiginous
with wavy borders, resembling a snake
universal
all areas of the body involved, with no areas of normal appearing skin
ecchymoses
Bruises, larger areas of hemorrhage. In older adults bruising is
common. Certain drugs such as aspirin, warfarin, and corticosteroids
and low platelet counts lead to easy or excessive bruising.
Anticoagulants and decreased numbers of platelets disrupt clotting
action, resulting in ecchymosis.
Palpation
Wash hands thoroughly before and after palpating a patient's skin.
Use gloves to examine nonintact skin and use standard precautions when
skin areas are draining. Subtle changes, such as the differences
between a fine macular (flat) rash and a
papular (raised) rash, are best determined by
palpating with your eyes closed.
Vascular changes
May be normal or abnormal. Normal markings include birthmarks, cherry
angiomas, spider angiomas, and venous stars. Bleeding into the skin is
abnormal and results in purpura, petechiae, adn eccymosis.
Petechiae
Small, reddish purple lesions that do not fade or blanch when
pressure is applied. They often indicate increased capillary
fragility. Petechiae of the lower extremities often occur with stasis
dermatitis, a condition usually seen with chronic venous insufficiency.
Ecchymoses
Bruises; large areas of hemorrhage. Certain drugs (aspirin, warfarin,
corticosteroids) and low platelet counts lead to easy bruising.
Anticoagulants and decreased numbers of platelets disrupt clotting
action, resulting in ecchymoses.
Palpation
Wash hands thoroughly before and after palpating a patient's skin.
Use gloves to examine nonintact skin and use Standard Precautions when
skin areas are draining. Subtle changes, such as the difference
between a fine macular (flat) rash and a
papular (raised) rash, are best determined by
palpating with your eyes closed. Changes in skin temperature are
detected by placing the back of your hand on the skin surface. First,
make certain to have warm hands. Cold hands interfere with accurate
assessment and are uncomfortable for the patient. Always assess skin
turgor on the skin or the chest to avoid mistaking dehydration for dry skin.
Dandruff
The flaking that occurs with dandruff causes many people to
mistakenly think the scalp is too dry; however, it is a problem of
excessive oil production. If severe dandruff is not treated, hair loss
can occur.
Hair Assessment
Body hair loss, especially on the feet or lower legs, may occur with
decreased blood flow to the area and also is a part of aging.
Hirsutism is excessive growth of body hair or hair
growth in abnormal body areas. It may occur on the face of a woman as
part of aging, is one manifestation of hormonal therapy imbalance, and
can also occur as a side effect of drug therapy. If hirsutism is
present, look for changes in fat distribution and capillary fragility,
which can occur in Cushing's disease, and for clitoral enlargement and
deepening of the voice, which may indicate ovarian dysfunction.
Dystrophic
Abnormal appearing nails may occur with a serious systemic illness or
local skin disease involving the epidermal keratinocytes.
Nail Assessment
When assessing the older adult, observe for minor variations
associated with the aging process, such as a gradual thickening of the
nail plate, the presence of longitudinal ridges, or a yellowish gray discoloration.
Alterations in Nail Color
White
Horizontal white banding or areas of opacity
Significance: Chronic liver or kidney disease (hypoalbuminemia)
Generalized pallor of nail beds
Significance: Shock, anemia, early arteriosclerotic changes
(toenails), myocardial infarction
Alterations in Nail Color
Yellow-brown
Diffuse yellow to brown discoloration
Significance: Jaundice, peripheral lymphedema, bacterial or fungal
infections of the nail, psoriasis, diabetes, cardiac failure, staining
from tobacco, nail polish, or dyes, long-term tetracycline therapy,
normal aging (yellow-gray color)
Vertical brown banding extending from the proximal nail fold
distally
Significance: Normal finding in dark-skinned patients, Nevus or
melanoma of nail matrix in light-skinned patients
Alterations in Nail Color
Red
Thin, dark red vertical lines 1-3mm long (splinter
hemorrhages)
Significance: Bacterial endocarditis, trichinosis, trauma to the
nail bed, normal finding in some patients
Red discoloration of the lanula
Significance: Cardiac insufficiency
Dark red nail beds
Significance: Polycythemia vera
Alterations in Nail Color
Blue
Diffuse blue discoloration that blanches with pressure
Significance: respiratory failure, methemoglobinuria, venous
statis disease (toenails)
Nail Assessment
In older patients, look for a "heaped up" appearance of the
toenails, which occurs with fungal infection
(onychomycosis). A warm water soak or lubrication
with petroleum jelly is required to soften the nail plates before they
can be trimmed. Soft nail plates, which are thin and bend easily with
pressure, are associated with malnutrition, chronic arthritis,
myxedema, and peripheral neuritis. Splitting of the nail bed is caused
by repeated exposure to water and detergents, which damage the plate
over time.
Nail Assessment
Separation of the nail plate from the nail bed
(onycholysis) creates an air pocket beneath the
plate. The pocket first appears as a grayish white opacity. The color
changes as dirt and keratin collect in the pocket, and the area begins
to have a bad odor. This problem occurs with fungal infections and
after trauma. Separation o the nail plate may also occur with
psoriasis or with prolonged chemical contact.
Acute paronychia
Inflammation of the skin around the nail, often occurs with a torn
cuticle or an ingrown toenail.
Chronic paronychia
Is common and is an inflammation that persists for months. People at
risk for chronic paronychia are those with frequent exposure to water,
such as homemakers, bartenders, laundry workers, and nurses.
Assessing Changes in Dark Skin
Cyanosis- examine lips and tongue for gray color;
examine nail beds, palms, and soles for blue tinge; examine
conjunctiva for pallor.
Inflammation- compare affected area with nonaffected
area for increased warmth; examine the skin of the affected area to
determine whether it is shiny or taut or pits with pressure; compare
the skin color of affected area with the same area on the opposite
side of the body; palpate the affected area and compare it with
unaffected area to determine whether texture is different (affected
area may feed hard or woody)
Jaundice- check for yellow tinge or oral mucous
membranes, especially the hard palate; examine the sclera nearest to
the iris rather than the corners of the eye
Bleeding- compare the affected area with the same
area on the unaffected body side for swelling or skin darkening; if
the patient has thrombocytopenia, petechiae may be present on the oral
mucosa or conjunctiva.
Skin Assessment for Patients with Darker Skin
Pallor can be detected in people with dark skin by first inspecting
the mucous membranes for an ash gray color. If the lips and the nail
bed are not heavily pigmented, they appear lighter than normal for
that patient. With decreased blood flow to the skin, brown skin
appears yellow-brown and very dark brown skin is ash gray.
Lab Test
Always wear gloves (use Standard Precautions) when examining skin
that is not intact.
Lab Test
Fungal infection
Cultures for fungal infection are obtained by using a tongue blade
and gently scraping scales from skin lesions into a clean container.
Collect fingernail clippings and hair in a similar container. Waiting
for culture results can delay treatment of a superficial fungal
infection. For this reason, the specimen is also treated with a
potassium hydroxide (KOH) solution and examine microscopically. For
deeper fungal infections, a piece of tissue is obtained for culture.
The physician obtains a specimen by punch biopsy.
Lab Test
Cultures for Bacterial Infection
Obtained from intact lesions (bullae, vesicles, or pustules). Collect
with a cotton tip applicator, and place material on a bacterial
culture medium for laboratory. For intact lesions, unroofing (lifting
or puncturing of the outer surface) may be needed using a sterile
small gauge needed before the material can be expressed. For deep
bacterial infection, inject nonbacteriostatic saline deep into the
tissue then aspirate it back; use the aspirate for culture. Viral
culture specimens are placed on ice immediately after specimens are
obtained and are transported to the lab as soon as possible.
Lab Test
Cultures for viral infections
Cultures for viral infections are indicated if a herpes virus is
suspected. Use a cotton tip applicator to obtain vesicle fluid from
intact lesions.
Skin Biopsy
A small piece of skin tissue may be obtained for diagnosis or to
assess the effectiveness of an intervention. Procedure: Establish a
sterile field. After removal, tissue specimens for pathologic study
are placed in 10% formalin for fixation. Specimens for cultures are
placed in sterile saline solution.
Punch Biopsy
Most common technique. A small circular cutting instrument, or
"punch" ranging in diameter from 2-6mm is used. After the
site is injected with a local anesthetic, a small plug of tissue is
cut and removed. The site may be closed with sutures or may be allowed
to heal without suturing.
Shave Biopsy
Shave biopsies remove only the portion of the skin that rises above
the surrounding tissue when injected with a local anesthetic. A
scalpel or razor blade is moved parallel to the skin surface to remove
the tissue specimen.
Excisional Biopsy
Excisional biopsy is rarely used for skin problems. When needed,
larger or deeper specimens are obtained by deep excision with a
scalpel followed by closure with sutures.
Macules
Freckles, flat moles, or rubella.
Flat lesions of less than 1cm in diameter. Their color is different
from that of the surrounding skin-most often white, red or brown.
Nodules
Lipomas.
Are elevated marble-like lesions more than 1cm wide and deep.
Patches
Macules that are larger than 1cm in diameter. They may or may not
have some surface changes-either slight scale or fine wrinkles.
Cysts
Nodules filled with either liquid or semisolid material that can be expressed.
Papules
Warts or elevated moles.
Small, firm, elevated lesions less than 1cm in diameter.
Vesicles (acute dermatitis) and Bullae (second degree burns)
Blisters filled with clear fluid. Vesicles are less than 1cm in
diameter, and bullae are more than 1cm in diameter.
Plaques
Psoriasis or seborrheic keratosis.
Elevated, plateau-like patches more than 1cm in diameter that do
not extend into the lower skin layers.
Pustules
Acne and acute impetigo.
Are vesicles filled with cloudy or purulent fluid.
Wheals
Urticaria, insect bites.
Are elevated, irregularly shaped, transient areas of dermal edema.
Erosions
Varicella.
Wider than fissures but only involve the epidermis. They are often
associated with vesicles, bullae, or pustules.
Scales
Exfoliative dermatitis and Psoriasis.
Visibly thickened stratum corneum. They appear dry and are usually
whitish. They are seen most often with papules and plaques.
Ulcers
Stage 3 pressure sores.
Deep erosions that extend beneath the epidermis and involve the
dermis and sometimes the subcutaneous fat.
Crusts and oozing
Eczema, late-stage impetigo.
Composed of dried serum or pus on the surface of the skin, beneath
which liquid debris may accumulate. Crusts frequently result from
broken vesicles, bullae, or pustules.
Lichenifications
Chronic dermatitis.
Palpably thickened areas of epidermis with accentuated skin
markings. They are caused by chronic rubbing and scratching.
Fissures
Athletes foot.
Linear cracks in the epidermis that often extend into the dermis.
Atrophy
Striae (stretch marks) and aged skin.
Characterized by thinning of the skin surface with loss of skin
markings. The skin is translucent and paper-like. Atrophy involving
the dermal layer results in skin depression.
Nail Assessment
Clubbing
Early clubbing: Hypoxia, lung cancer. Nail base spongy when palpated.
Late Clubbing: Prolonged hypoxia, emphysema, COPD, advanced lung
cancer, cystic fibrosis, chronic heart failure. Visibly edematous and
spongy when palpated. Fingertips give a drum stick appearance when
viewed from above.
Spoon nails (Kolionychia)
Early: Iron deficiency, poorly controlled diabetes, local injury.
Late: Psoriasis, chemical irritants, developmental abnormality.
Beau's grooves
Horizontal depressions in the nail plates caused by growth arrest.
Acute severe illness, prolonged febrile state, isolated periods of
severe malnutrition.
Pitting
Small, multiple pits in the nail plate, may be associated with plate
thickening and onycholysis.
Psoriasis, alopecia areata