Pathophysiology ch.41 Structure, Function, and Disorders of the Integument

name the layers of skin

Epidermis: superficial/outer layer of skin
Dermis: the "true skin"
Hypodermis (subcutaneous layer): lowest layer of the skin

what are dermal appendages?

nails, hair, sebaceous glands and the eccrine glands

Eccrine glands are found all over the body, but increase in number where?

palms of the hands, soles of the feet, and forehead.

where are apocrine sweat glands found?

near the bulb of hair follicles

blood supply to the surface of the skin is delivered via...?

papillary capillaries

what supplies O2-rich blood to the papillary capillaries?

subcapillary arteries

what carries deoxygenated blood away from the papillary capillaries through capillary loops?

subcapillary veins

papillary capillaries play an important role in...

regulating body temp at the surface of the skin

Alpha adrenergic receptors are signaled by the sympthatic NS to _____________ and ____________. This process regulates blood flow and impacts the temperature of the skin.

vasoconstrict, vasodialate

name a few things that happens to our skin when we age.

-It becomes thinner, dryer, wrinkled and demonstrates a change in pigmentation do too few were melanocytes
-There are fewer Langerhans cells, which reduce the skins immune response
-There is atrophy of the sebaceous, eccrine and apocrine glands, which cau

pressure ulcers result from (4 most common)

unrelieved pressure, sheer force, friction and or moisture

decubitus ulcers are the result of...

recumbent positioning over a long period of time
(aka bedsore)

where are pressure ulcers most likely to develop? and name the 4 most common

bony prominences: sacrum, heels, ischia and the greater trochanters

stage 1 pressure ulcer

non-blanching, red skin that is intact

stage 2 pressure ulcer

partial-thickness skin loss (erosion of the skin or a blister) involving the epidermis or dermis

stage 3 pressure ulcer

Full-thickness skin loss involving damage or necrosis of subcutaneous tissue that may extend to underlying fascia

stage 4 pressure ulcer

Full-thickness tissue loss with exposure of muscle, bone, or supporting structures (may include undermining and/or tunneling)

what are keloids?

excessive collagen formation during dermal connective tissue repair that are elevated, rounded, and firm with claw-like margins that extend beyond the original site of injury

risk factors for keloids

Poorly aligned skin/tension on the wound, foreign material at affected site, infection, and certain traumas (e.g., burns)

what is pruritus?

itching"
-either localized or generalized and can move from one location to another.
-It may be associated with a specific skin disorder or could be a manifestation of a systemic health issue.

what do pain and pruritus have in common?

they share a common pathway in the spinal cord and often activate similar sensory areas in the brain.

Skin disorders may be the result of

trauma, abnormal cell function, infection, and/or systemic diseases.

there are various types of dermatitis characterized by

-pruritus
-lesions with indistinct borders
-epidermal changes (such as eczema).
These lesions may involve erythema, papules, or scales.

Allergic contact dermatitis is caused by

a delayed, hypersensitivity type IV reaction. (exposure to some irritant)
Ex: poison ivy

delayed hypersensitivity reaction

a response that occurs hours after an immunologic response.

Irritant contact dermatitis

a non-immunologic inflammation of the skin involving chemical irritation from acids or prolonged exposure to irritating substances.

Folliculitis
(+risk factors)

a bacterial infection on the hair follicle
(prolonged skin moisture, skin trauma, poor hygiene)

Cellulitis
(+risk factors)

infection in the dermis and subcutaneous tissue. S. aureus is common pathogen.
(complication of a wound or ulcer)

where are HSV-1 infections located? spread by?

-oral/facial
-infected saliva

where are HSV-2 infections located?

-genitals
-skin-to-skin and mucous membrane contact during viral shedding

herpes zoster

-shingles
-caused by re-activation of the latent infection of herpes varicella

herpes varicella

chicken pox

candidiasis

a yeast-like fungus commonly found on mucous membranes, within the gastrointestinal tract, and in the vagina.
-Candida albicans is the primary fungus responsible for yeast infections.

three types of skin cancer

-basal cell carcinoma: most common occurrence
-squamous cell carcinoma:
-cutaneous melanoma:most commonly associated with death.

basal cell carcinoma
-caused by
-who is at risk
-where

-caused by ultra-violet radiation
-High risk factors for those with light colored skin and those receiving intense sunlight exposure
- face/head and neck

squamous cell carcinoma
-two types
-caused by
-risk factors
-where

-in situ (Bowen disease) and invasive
-caused by ultraviolet radiation
-Arsenic exposure within drinking water, increased exposure to gamma rays/x-rays, immunosuppression, and light-colored skin
-head, neck, and hands

cutaneous melanoma
-caused by
-risk factors
-prognosis

-Malignant degeneration of melanocytes
-Genetic predisposition, ultraviolet radiation
-5-year survival rate

ABCDE of examining a mole

A: asymmetry
B: border irregularity
C: color variation
D: diameter >6mm
E: elevation

4 types of burns

thermal, chemical, electrical, radioactive

1st degree burns

superficial, only involve the epidermis. heal within 3-5 days w/o scaring

2nd degree burns

superficial partial-thickness burns: involves blisters and take 3-4 weeks to heal
deep partial-thickness burns: injury to the entire dermis, yet hair follicles and sweat glands remain in tact

3rd degree burns

Full thickness burns involve destruction of the entire epidermis, dermis, and often underlying subcutaneous tissue

Estimating Burn Injury: Head (one side)

4.5%

Estimating Burn Injury: trunk (one side)

18%

Estimating Burn Injury: arm (one side)

4.5%

Estimating Burn Injury: genitals

1%

Estimating Burn Injury: leg (one side)

9%

The nurse is caring for a patient who sustained first degree burns to his entire right arm and anterior right leg. Using the 'rule of nines' (Browder chart), what is his estimated total body surface area (TBSA) burned?

18%

Of the sweat glands, the _____ glands are most abundant in the axillae and genital areas.

apocrine

. A 23-year-old male reports a rash and pruritus. An increase in _____ is associated with pruritus?
A. Substance P
B. Norepinephrine
C. Dopamine
D. Acetylcholine

acetylcholine

A patient wants to know which malignant skin lesion is the most serious. The correct response is

Malignant melanoma