Wound Healing - Class 5 Flashcards
epidermal healing response
begins w/in 24-48 hours
what do the epithelial cells do –> epidermal healing
detach from the basal layer
migrate across the wound
proliferate by mitosis
differentiate into mature epidermal cells
contact guidance –> epidermal healing
when epithelial cells contact each epithelial cells
they change direction
contract inhibition –> epidermal healing
when the epithelial cells are contact on all sides by other epithelial cells
they stop migration
dermal healing has
3 phases
3 phases of dermal healing
inflammatory
fibroblastic
maturation
fibroblastic phase includes
collagen synthesis
wound contraction
collagen synthesis
amino acids link together to form polypeptide chains
amino acids are hydroxylated and the chain is called protocollagen
protocollagen
3 protocollagen chains are twisted together to form a helix called tropocollagen
tropocollagen
multiple tropocollagen units form collagen filaments
collagen filaments
bundles of filaments make a fibril
fibrils form a fiber
wound contraction
active process d/t fibroblasts/myofibrils
what do the fibroblasts and myofibrils do –> wound contraction
attempt to close a wound in which a loss of tissue has occurred
amount of contraction is dependent on –> wound contraction
amount of available mobile skin around the defect
what would cause wound contraction to stop
edges meet
tension in the surrounding skin equals or exceeds the force of contraction
what may decrease contraction
skin grafts
scaring
ration of collagen breakdown to production determines the type of scar that forms
if rate of breakdown exceeds production
scar becomes softer and less bulky
if rate of production exceeds breakdown
then a hypertrophic scar may result
hypertrophic scar
enlarged red
raised
rigid scar
stays w/in the boundary of the original wound
keloid scar
large
firm scar
extends beyond the boundaries of the initial wound
factors which may impede wound healing
age
body structure
stress
nutrition
drugs
smoking
age
< 2
> 65
less nutritional stores
inadequate immune system
body structure
obese
emaciated
obese
blood supply to tissue
decreased cell proliferation
emaciated
decrease energy stores
decreased time metabolism
stress
inhibits cell proliferation
nutrition
need vitamin C
zinc
iron for collagen formation
drugs
steroids
ASA
decrease inflammation and epithelialization
smoking
decreases oxygenation to tissue
vasoconstriction
types of wound healing
primary intention
secondary intention
tertiary intention
skin grafting is
surgical procedure w/ dermatome
skin grafts can be
allograft
xenograft
allograft
homograft
same species
cadaver
xenograft
heterograft
another species
porcine
where is an artificial skin graft used
where large areas of burn exist
coverage is done for survival
split thickness skin graft (STSG)
consists of epidermis and portion of underlying dermis
types of artificial skin grafts
meshed
sheet
meshed skin graft
expands the donor skin to provide more coverage of burn wound w/ less skin
what does a meshed skin graft leave
waffle appearance
will not go away
when is a meshed skin graft better
infected wounds
wounds w/ irregular contours
sheet skin graft is better for
more cosmetic
sheet skin grafts are
more durable
contraction is limited
STSG –> sheet
may contract more while healing more than FTSG
FTSG leave a –> sheet
full thickness lesion
what contract less –> sheet
non-meshed
PTs shouldnt –> grafts
move a grafted area for 5 days
during txs keep elevated
LE grafts
can move after 5 days
should hold off ambulation for approximately 5-6 days
–> depending on how the grafts look
dermal implants
integra
inhalation injuries
increase severity of the injury
types of inhalation injuries
thermal
chemical
CO poisoning
dx of inhalation injuries
facial burns
singed nasal hairs
tinged sputum
closed space injury
blood work
bronchoscopy findings
hoarseness
pathophys of inhalation injuries
inflammation can cause mechanical obstruction
necrosis of damaged epithelium, mucosal sloughs
bronchopneumonia is likely in severe cases
decreased pliability of the lungs, aspect of restrictive device
rehab considerations –> inhalation injuries
airway should be secure
pt should have good O2 sats
monitor for respiratory distress
promote mobilization of secretions
nutrition
requirements are high for the burn pt
additional energy is required to promote wound healing
if the body’s caloric intakes are not met
body may resort to muscle breakdown
if pt doesnt meet their caloric requirements
NG tube
what may the pt require –> calories
4000-5000 per day
children require even greater amount of calories per day
