Anatomy Unit 5B Test Prep

How many conditions can affect the skin?

Over 1,000 different conditions and ailments

Why is skin important for detecting internal disease?

Many internal diseases reveal themselves on the skin

What are the most common skin disorders?

Infections

Which skin disorders are less common but more damaging?

skin cancer and burns

Are most skin tumors cancerous?

No - most are benign and do not metastasize

what does metastasize mean?

To spread to other parts of the body

Two main risk factors for skin cancer

Overexposure to UV radiation

Frequent irritation of skin

How can some skin lotions help prevent skin cancer?

they contain enzymes that repair damaged DNA

Three major types of skin cancer

Basal cell carcinoma

Squamous cell carcinoma

Melanoma

Most common and least malignant skin cancer

Basal cell carcinoma

what cells are involved in basal cell carcinoma

stratum basale cells

how does basal cell carcinoma spread

slowly invades dermis and hypodermis

treatment success rate for basal cell carcinoma

99% cured by surgical excision

second most common skin cancer

squamous cell cercinoma

which cells are affected in squamous cell carcinoma

keratinocytes of the stratum spinosum

can squamous cell carcinoma metastasize

yes

typical appearance of squamous cell carcinoma

scaly, reddened papule

common locations for squamous cell carcinoma

scalp

ears

lower lip

hands

prognosis and treatment for squamous cell carcinoma

good prognosis if treated with radiation or surgery

most dangerous type of skin cancer

melanoma

what cells does melanoma affect

melanocytes

why is melanoma so dangerous

highly metastatic

resistant to chemotherapy

treatment for melanoma

wide surgical excision

immunotherapy

key to survival from melanoma

early detection

what does the ABCD rule help detect

Melanoma

ABCD - A

asymmetry (two sides do not match)

ABCD - B

Border irregularity (indentations)

ABCD - C

Color variation (black, brown, tan, red, or blue)

ABCD - D

Diameter > 6 mm (pencil eraser size)

what causes burns

heat, electricity, radiation, or chemicals

how do burns damage tissue

denaturation of proteins, destroying cells

immediate life-threatening concern with burns

dehydration and electrolyte imbalance

why are dehydration and electrolyte imbalance dangerous

can cause renal shutdown and circulatory shock

purpose of the rule of nines

estimates fluid loss from burns

how is the body divided in the rule of nines

11 sections 9% each

genitals 1%

first degree burns affect which layer

epidermis only

symptoms of first degree burns

redness, swelling, pain

second degree burns affect which layers

epidermis and upper dermis

key sign of second degree burns

blisters

what are partial thickness burns

first and second degree burns

third degree burns involve what depth

entire thickness of skin

other name for third degree

full thickness burns

skin appearance of third degree burns

gray white, cherry red, or blackened/charred

why are third degree burns not painful

nerve endings destroyed

common treatment for third degree bruns

skin grafting

when are burns considered critical

>25% second degree

>10% third degree

third degree on face, hands, or feet

burn treatment step: removal of damaged skin

debridement

other burn treatments

antibiotics

temporary coverings

skin grafts

what happens when body barriers are compromised

inflammatory and immune responses activate

how quickly does tissue repair begin

very quickly

what process is responsible for repair

inflammation

two major ways tissue repair occurs

regeneration and fibrosis

regeration

same tissue replaces damaged tissue (function restored)

fibrosis

connective tissue replaces tissue (function lost)

step one of tissue repair

inflammation sets the stage

effects of inflammatory chemical

blood vessel dilation

increased permeability

what happens to blood during step 1

clotting occurs

step two of tissue repair

organization restores blood supply

what replaces the blood clot

granulation tissue

what is granulation tissue

new tissue rich in capillaries

role of fibroblasts

produce collagen fibers to bridge the gap

what happens to debris

it is phagocytized

step three of tissue repair

regeneration and fibrosis

what happens to the scab in step 3

it detaches

what happens to fibrous tissue in step 3

it matures

final result of tissue repair

regenerated epithelium with underlying scar tissue

what is the order of pain for burns

3rd, 1st, 2nd

why are second degree burns the most painful

burn is very deep but the nerve ending are still in tact

why would you not want to fully suture closed a wound

if it is a bite because the bacteria from the teeth would get stuck inside and cause infection (just cover it)

what does it mean to be phagocytized

for a cell (a phagocyte) to engulf, ingest, and digest solid particles like bacteria, dead cells, or debris

1st degree burn visual

2nd degree burn visual

3rd degree burn visual

basal cell carcinoma visual

squamous cell carcinoma visual

melanoma visual

What is the rule of nines used for

measures the volume of fluid loss