Scars and Burns

Avulsion

section of skin gets torn away and may form a flap

Puncture

sharp objects penetrates the skin, can be very deep, higher risk of injection because it is harder to flush out bacteria

Laceration

skin torn or ripped by jagged/rough object, edges rough/jagged

Incision

skin sliced by sharp object, edges of wound neat and smooth

Abrasion (scrape)

layers of skin scrapped by rough surface. higher risk of infection because larger area of exposed skin and takes longer to heal

Contusion (bruise)

bleeding under the skin caused by blunt force trauma, blood vessels broken by impact, "closed injury", no risk of infection

Hemostasis

1 stage of healing, main goal is to stop blood loss, and blood vessles constrict to reduc blood loss, lasts 10 minutes, platelets and fibrin create blood clot at wound site

fibrin

protein

scab

crust that forms over a wound or sore during healing, clot create scab as it dries

inflammation

prevent infection, platelets release histamine

histamine

common chemical in bodies involved in inflammation, induces vasodilation and causes fluids to leak into area around wound

vasodilation

dilation of blood vessels

macrophages

type of white blood cell, destroy bacteria

Proliferation

rebuild lost tissue, fibroblasts migrate to wound site, create collagen build new connective tissue

Angiogenesis

new blood vessels grow into wound site, epithelial cells divide and start to fill wound from edges

Maturation and remodeling

refine new tissue that was built in a hurry, scab falls off, collagen fibers get rearranged modified, scar tissue may form

scar

different from regular skin, higher tan usual ratio of collagen to cells, collagen fibers orientated in one direction, strong but flexible, often less protection from UV

regular scar

flat, same size as original wound

hypertrophic scar

raised but same size as original wound

keloid scar

raised and extends beyond wound boundaries, can get very large

atrophic scar

pitted/concave, same size as original wound

first degree burn

damage to epidemris only, heals quickly, no risk of infection, scarring

second degree burn

damage to epidermis and part of dermis, dark pinky to waxy white appearance, blisters, more painful than first degree burns, risk of infection if blisters rupture

third degree burn

damage down to lower dermis or subcutaneous layer, epithelial tissue destroyed, may be numb( blood vessels and nerves destroyed), high risk of infection, shock and dehydration, may require skin graft, healing takes a long time

infection

proliferation of harmful bacteria in the body

dehydration

decrease in volume of fluid in body

hypovolemic shock

excessive blood loss