Integumentary System. Three main layers of tissue make up the skin Epidermis Dermis Hypodermis.

Integumentary System

Three main layers of tissue make up the skin

• Epidermis• Dermis• Hypodermis

Epidermis

•The Outermost layer of skin•Avascular•Complete regeneration approximately 35 days

Dermis•Also called corium or “true skin”.•Contains blood vessels, nerves, involuntary muscle, sweat and oil glands and hair follicles.

Hypodermis (Subcutaneous Fascia)• Innermost layer of

skin• Made of elastic

and fibrous connective tissue and adipose tissue•Connects skin to

underlying muscles

Two main types of glands

•Sudoriferous Glands•Sebaceous Glands

Sudoriferous Glands (Sweat Glands)

•Coiled tubes.•Extend through dermis and open on surface of skin at pores.•Sweat eliminated by these glands.

Sebaceous Glands•Oil glands.•Usually open to hair follicles.•Produces sebum which is an oil that keeps skin and hair from becoming dry and brittle.

Hair & NailsHair•Each hair

consists of root which grows in hollow tube (follicle) and a hair shaft.•Helps protect

body.

Hair & NailsNails•Consist of dead epithelial cells packed closely together to form thick, dense surface.•Formed in nailbed.

Function of Integumentary System

Protection• Serves as barrier

to sun’s ultraviolet rays and invasion of pathogens (germs).•Hold moisture in .• Prevents deeper

tissues from drying out.

Sensory Perception•Nerves in skin help body to respond to pain, pressure, temperature, and touch sensations.

Body Temperature Regulation•Blood vessels dilate- excess heat from blood escapes through skin.•Blood vessels constrict – heat is retained in body.

Waste Disposal•Excretion of oil, water, sodium and carbon dioxide.

•

•Vitamin D production.

PigmentationMelanin•Only pigment

made in skin.• Yellow to reddish-

brown to black• Absorbs

ultraviolet light to tan skin.• Gives color to

hair, skin, and the iris

Karotene•Yellowish-red pigment•Can help determine skin color.

Abnormal Skin ColorsJaundice • Yellow

discoloration of skin.•Can indicate

bile in blood due to liver or gallbladder disease

Erythema•Reddish color of skin.•Due to burns or congestion of blood vessels

Cyanosis•Bluish

discoloration of skin.•Caused by

insufficient oxygen.•Associated with

heart, lung, and circulatory diseases or disorders.

• Acne – overactive secretion of sebaceous glands.• Pimples and

blackheads.• Teens to early twenties.• Rx: Thorough washing,

steroid creams, UV light, avoidance of certain foods, chemical face peel.

Skin Diseases and Disorders

Eczema• Vesicles or reddened skin which burst and weep

a crust ( dried pus and blood)• Most common inflammatory disorder of the skin• Rx: Tranquilizers, antihistamines, wet dressings,

starch baths.

Psoriasis

• Psoriasis – Red thick areas covered with white or silver scales• Chronic,

noncontagious, inherited skin disease• Rx: No Cure• Cortisone Ointments• Ultraviolet Light• Removal of Scales

A-J display appearances of psoriasis lesions on typical areas of the skin. Lesions can be present on any area of the body. D is an example of minimal psoriasis. K-M are examples of psoriasis affecting fingernails. Although psoriasis-affected toenails can look very similar to this, people with athlete's foot may have similar-appearing toenails; therefore it is better to judge psoriasis by fingernail appearance alone. K and L display nail pits. M shows characteristic yellowish or brown color known as an "oil spot."

Contact Dermatitis• Redness, itching, blisters, edema• Caused by poison ivy, poison oak, cleansing

agents, cosmetics, etc.• Rx: Wash with soap and water then apply

alcohol and antipruritic (relieves itching) lotions.

Impetigo• Erythema, vesicles with sticky yellow crusts• Very contagious.• Infection with staph or strep• Rx: Remove crusts and apply antibiotic

ointment

Warts

• Caused by virus.• Painless except for plantar warts.• Rx: Nitric or sulfuric acid deep into root of wart

or freezing with liquid nitrogen.

Scleroderma• systemic autoimmune disease of skin, muscles,

bones, heart, lungs. Skin becomes hard and tight.• Progressive disease. Mainly affects women in child

bearing years. Considered an auto immune disease• Rx: Ointment, heat, massage, steroids.

Skin Cancer• Definition: neoplasms or abnormal growth

of cells that originate in the epidermis.• More than 800,000 new cases each year in

the USA• One in five people in the US will develop

skin cancer in his/her lifetime. This number jumps to one in three in the Sunbelt states.• Three Major Types of Skin Cancer• Basal Cell, Squamous Cell, Malignant

Melanoma

Skin Cancer• Basal Cell Carcinoma• Most common type of skin cancer• Malignancy begins in cells at the base of the

epidermis and most often appears on the nose and face• Incidence increases after age 40• Basal cell tumors rarely metastasize but may cause

wide-spread destruction of normal tissue if left untreated

Skin Cancer• Squamous Cell Carcinoma• Slow-growing• Arises from the epidermis• Most frequently occurs in middle-aged and elderly

individuals• Typically found on sun-exposed areas of skin• May metastasize but is not likely to spread to other

body areas.

Skin Cancer• Malignant Melanoma• Most deadly of all skin

cancers• Steady increase in

incidence of 4% per year over last 20 years

• Median age of diagnosis is 53 years

• Sometimes develops from a pigmented Nevus (mole) to become a dark spreading lesion

• Most likely to metastasize

Skin Cancer

•Malignant Melanoma

Skin Cancer http://www.skincancer.org/

• “ABCD” Rule of Self-Examination of Moles• Asymmetry: Lesion halves are

not mirror images of each other giving a lopsided appearance

• Border: Irregular or indistinct borders

• Color: Unevenly colored, exhibiting a mixture of shades or colors

• Diameter: By the time lesions exhibit characteristics A, B, and C, it is probably larger than 6mm or ¼ inch

BURNS• Burn is an injury that

can be caused by fire, heat, chemical agents, radiation and/or electricity

• Classification of burns: Severity of burn is determined by depth of lesion and percent of body surface burned.

Burns• First-degree or superficial• Least severe type of burn• Involves only top layer of

skin, the epidermis• Usually heals in 5 to 6 days

without permanent scarring• Skin is reddened or

discolored• May have some mild swelling• Victim feels pain• Three common causes• Overexposure to sun or mild

sunburn• Brief contact with hot objects

or steam• Exposure of skin to weak acid

or alkali

Burns• Second-degree or partial-

thickness• Usually causes injury to top layers

of skin and involves both epidermis and dermis

• Blister or vesicle forms• Skin is red or has mottled

appearance• Swelling occurs along with severe

pain• Surface of skin appears to be wet• Painful burn that may take 3 to 4

weeks to heal• Three common causes• Excessive exposure to sunlamp

or artificial radiation or severe sunburn

• Contact with hot or boiling liquids

• Burns from fires

Burns• Third-degree or full-thickness

• Third-degree or full-thickness• Most severe type of burn• Involves injury to all layers of skin in

addition to underlying tissue• Area has a white or charred

appearance• Can be extremely painful or relatively

painless if nerve endings are destroyed

• Can be life-threatening because of fluid loss, infection, and shock

• Common causes• Exposure to fire or flames• Prolonged contact with hot objects• Contact with electricity• Immersion in hot or boiling liquids

Burns• Methods to Determine

Percent of Body Surface Burned

• “Rule of Palms”: Based on the assumption that palm size of burn victim is about 1% of body surface. Estimating the number of “palms” burned will approximate the percentage of body surface involved.

Burns• Methods to Determine

Percent of Body Surface Burned• “Rule of Nines”: • 9% of total skin area covers

head and each upper extremity, including front and back surfaces

• 18%of total skin area covers each of the following:• front of trunk• back of trunk• each lower extremity including

front and back surfaces

Burns• Methods to Determine

Percent of Body Surface Burned• Lund-Browder Charts:• Permits more accurate

estimates of burned surface area in children

• Makes allowances for large percent of surface are in certain body regions in children such as the head

Burns• Medical help for burns• Usually not required for first-degree or superficial burns• Should be obtained if:• More than 15% of adult’s body is burned• More than 10% of child’s body is burned• Rule of nines is used to calculate the percentage of body

surface burned• Burns affect face or respiratory tract• Victim is having difficulty breathing• Burns cover more than one body part• Victim has a partial-thickness burn and is under 5 or over 60

years of age• Burns result from chemicals, explosions, or electricity

Burns• All third-degree or full-thickness burns should

receive medical care• First aid for superficial and mild partial-thickness

burns with closed blisters• Cool area by flushing with large amounts of cool water• Do not use ice or ice water because it causes body to lose

heat• Use dry, sterile gauze to blot area dry• Apply dry, sterile dressing (nonadhesive or nonstick is best)

to prevent infection• Elevate affected part if possible to reduce swelling• Do not apply oils, grease, butter or other substances unless

instructed to do so by physician• Do not break or open any blisters as this creates an open

wound prone to infection

Burns• First aid for severe second-

degree and full-thickness or third-degree burns• Call for medical help immediately• Cover burned area with thick,

sterile dressings• Elevate Hands or feet if they are

burned• Do not allow victim to walk if

feet or legs are burned• Do not attempt to remove

particles of clothing from burn• Watch for respiratory distress or

signs of shock

BurnsBreakdown of Major Causes of Burns

Flame 33%

Scald 30%

Contact 15%

Flash 10%

Electrical 5%

Friction 1%

Radiation 1%