Unit 2 Integumentary Test

Functions of the Skin

protection → from trauma and pathogens & UV radiation

waterproofs skin

sweating regulates body temperature

layers of the skin

epidermis, dermis, hypodermis

layers of epidermis

stratum basale (bottom layer), stratum lucidum (middle layer), stratum corneum (top layer)

what does the stratum basale include

superior to dermis
constantly dividing cells that go up to the dermis each division and then eventually die off because there is no blood supply
melanocytes present (pigment cells)
sensory receptors here (pain & temp sensations)
tactile cells → touch receptors

what does the stratum lucidum include

calluses form here
only in thick skin areas
protection from friction

what does the stratum corneum include

flat hard cells
keratinization occurs here → living skin cells turn into tough, dead, waterproof protein filled cells
protects body from water loss and gives barrier to microbes

What does the dermis include

thickest layer of the skin
sebaceous glands

dermal papillae
hair
arector pili
dense connective tissue
sweat glands
blood vessels

what are sebaceous glands

duct empties into follicle so hair follicle and sebaceous gland is connected
secrete sebum
lubricates hair and skin
waterproofing
kills bacteria
acne caused by inflammation

what is the dermal papillae

connects to epidermis
fingerprints
little bump stuff

what is hair

follicles in dermis
initially fed by blood supply
cells pushed to the top and die
root/shaft
alopecia → immune system attacks hair follicles

what is the arector pili

what are dense connective tissue

contains collagen/elastic fibers → keeps skin firm and plump and bounce and allow it to movie with your facial expressions

sweat glands

90cm² on leg
400 cm² on hand & feet
coiled & tubular
lowers body temperature → water holds in heat b/c high specific heat so releasing the water also releases the heat

blood vessels

present causing blushing/pallor/cyanotic

what is in the hypodermis

subcutaneous tissue
loose connective tissue
nerves
adipose

arteries & veins

function —> energy storage, insulation, absorb shock

what is adipose

fat tissue
insulates the body
padding against injury

is hypodermis considered part of the skin

not technically b/c hypodermis acts as a bride and thethers the skin to the underlying fascia, muscles, and bones
made of loose connective tissue & adipose instead of dense cellular layers designed for barrier protection & sensation

1st degree burn

superficial burn

epidermis

redness & pain → pain b/c of the pain receptors

no blistering

ex. moderate sunburn

2nd degree burn

entire epidermis into dermis

blistering → epidermis is pulling away from dermis & there is fluid

enlarges as time passes → heat is pushing the cells/speading them

10-14 day recovery

if deep into dermis 30-105 day recovery

3rd degree burn

full thickness burn

leathery

brown-red color skin

no pain

no sweating or hair growth

all the way from dermis into hypodermis

affects: blood supply, sebaceous glands so no oil, damaging nerves, sweat glands so you can’t regulate temperature

4th degree burn

tissue down to bone so burned through muscle

critical burn patient criteria

automatic → on face (lung damage), hands or feet (joint damage), front of chest near mouth opening

2nd degree burn 25% or more

3rd degree burn 10% or more

4th degree burn any amount

impetigo

contagious bacterial infection

athlete’s foot

fungal infection

itchy dermal skin condition

ringworm

fungal infection

psoriasis

chronic autoimmune disease

possibly hereditary

overactive cell division

pink/red patches w/ scales

excema

inflammation

sensitivity to chemicals

dandruff

increased rate of kerinization

causes flaking & itching

dry skin

can be caused by a yeast that eats oil on the skin

urticaria

hives

allergic reactions

red elevated patches

basal cell carcinoma

common type of skin cancer

UV radiation

immune system suppresses

surgical removal

recurrence is common

on surface of skin so epidermis → less serious b/c of this and doesn’t spread

to check → check margins for cancer cells and if clear no cancer

squamous cell carcinoma

excessive UV exposure
metastasis (can spread to nearby organs)

melanoma

melanocytes with cancer

spilled ink spot

irregular mole

skin around mole is red

ABCDE

• A → asymmetry

• B → border

• C→ color

• D → diameter

• E → evolving

kaposi’s sarcoma

skin cancer seen in AIDS patients

b/c of decreased immune system

responds to AIDS cocktail

moles

overgrowth of melanocytes

usually not cancerous

warts

viral infection

process of skin healing

hemostatis, inflammation, growth & rebuilding, strenghtening

hemostasis

stopping the bleeding → blood cells clump together and clot protecting the wound and preventing further blood loss

inflammation

once closed w/ clot blood vessels open a bit and allow fresh nutrients and oxygen into the wound for healing

white blood cells called macrophage take on role as wound protector and fight infection and oversees repair process

growth & rebuilding

blood cells arrive to help build new tissue
chemical signals tell cells to create collagen
scar eventually dulls from its red state

strengthening

tissue gets stronger → stretching, itching, & puckering of the wound

hair follicle

surrounds the hair root so in epidermis and dermis

hair root

inside follicle and extends down into dermis

hair shaft

visible part that extends out of the body surface
sweat glands
blood vessels

decubitus ulcers (bed sores)

decreased blood flow
areas with little fat and muscle over bony prominences are common sites
developed from pressure, shear (when two parallel forces move in opposite directions) and friction

lipsuction

fat removed from the body
taking the fat out of the hypodermis
popular areas: thighs, buttocks, abdomen and neck
10-15 lbs generally taken off

tattoos

ink into dermis b/c the epidermis skin falls off
tattoo removal → breaking the ink into smaller particles so the body eats it up

complications from burns

fluid loss → b/c of blisters, happens soon as pass 1st degree
heat loss → skin more open so lose heat
infection

rule of 9s

each entire arm (not hands) → 9%

each entire leg → 18%

perineum → 1%

entire torso + chest combo → 36%

entire head → 9%

healing of burns

dead skin removed

skin grafting → autografts, allografts

autografting

taking skin from own body

pros: permanent, body will accept it

cons: scarring, second wound site that has to heal

use for: deep partial/full thickness burns

allogradting

taking skin from other body
pros: readily available, can get a lot of skin

cons: body could reject it, temporary

use for: temporary wound coverage, when autograft isnt available

nails

special epithelial cells at base

visible part is nail body which is pink & vascular

grows 1mm/week

cuticle → thin layer of dead skin that is waterproof and protects underlying nail from bacteria, dirt, & infections

lunula → crescent shape thick layer of reproducing cells

thicker skin characteristics

offer more protection

has thicker stratum coreum and epidermis

no hair follicles and sebaceous glands

contains less sweat glands

less flexible

how does epidermis get oxygen & nutrients

from capillaries in dermis

oxygen & nutrients diffuse upward into the living skin part of the epidermis (stratum basale)

why cant full thickness burn heal on their own

affects all skin layers so there is no healthy skin to regenerate
blood vessels and nerve endings are destroyed so no oxygen and nutrients and those r needed for repair

why elevate burns?

to reduce fluid buildup and swelling

why r third degree burns not painful

b/c pain receptors/nerves r burned off

broad spectrum antibiotic

protection from infections and different kinds of bacteria, all around protection

escharotomy

surgical procedure where doctor cuts through the hard burn layer to relieve dangerous pressure

lymphatic system in wound healing

gives O2, nutrients, clotting proteins

integumentary system in wound healing

forms primary physical barrier against infection by traveling across wound and forming a protective epithelial layer

why heat helpful in wound healing

accelerates cellular activities so wound heals faster

types of wounds

abrasions, lacerations, puncture wounds, avulsions

abrasians

scrape where epidermis is rubbed off by rough surface

lacerations

deep cut/tear in skin w/ jagged/irregular edges

puncture wounds

deep narrow wound caused by sharp pointed object piercing the skin

avulsions

partial or complete piece of skin and underlying tissue forcibly torn away from the body