Cutaneous Wound Healing Flashcards
how thick is skin?
1.4 to 4 mm
epidermis is vascular or avascular?
avascular
what kind of tissue is the dermis?
loose connective tissue
hyperkeratosis is a thickening of what stratum layer of skin? Who usually has this?
stratum corneum - people with diabetes
what is maceration?
excess humidity of tissue - whitish skin (like when bandaid on too long)
eschar is what?
black crust from necrotic cutaneous or mucous covering
in partial thickness wounds, which cells are doing most of the healing work?
keratinocytes - reepithelialization from edges and areas around glands and hair follicles (epithelial buds)
in full-thickness wounds, what is the primary mechanism that healing uses? what kind of tissue is laid down?
wound contraction - scar tissue
what are the 4 stages of wound healing?
hemostasis
inflammatory
proliferation
remodelling
what type of environment is required for autogenic debridement?
humid
what three types of cells are involved in the proliferative stage?
fibroblasts
endo and epi thelial cells
when is a wound a chronic one?
4-12wks +
when it takes forever to heal and does not respond well to treatment
name four types of chronic wounds
pressure ulcers
venous ulcers
arterial ulcers
neuropathic ulcers
how long does one have to be immobile before pressure ulcers start?
only 1-2 hours
a stage one pressure sore is unbroken skin, but will do what when a persistently red area is pushed with a finger?
it will not whiten, it will remain red
stage two pressure ulcers involve loss of dermis or epidermis or both. What will this look like clinically?
looks like an abrasion, blister, or shallow crater, occasionally with fibrin and looking light red otherwise
Stage three goes down to the subcutaneous layer but not beyond underlying fascia. It will look like a deep crater. What else can be present?
sinus tracts and undermining. Necrotic tissue may also be present
stage four is all the way down and will have necrosis. what other structures might be affected?
muscle, bone, joint capsule
unspecified pressure sores may involve what?
eschar or humid necrotic tissue covering wound bed, so unable to tell stage of ulcer
does it hurt to push on pressure sores?
of course it is
with venous ulcers, venous distension leads to cells leaking out into tissues where they become brown and swollen. What is this browning called?
hemosiderin
what happens after the leaking and browning?
dermatosclerosis, and finally lipodermatosclerosis
venous hypertension can come from insufficient valves but also obstruction. What are two ways the veins may become obstructed?
obesity
pregnancy
thrombosis
what do venous ulcers usually look like?
shallow weirdly shaped on the bottom 1/3 of the legs. contains moderate exudate
may have swelling, hemosiderin, varicosities and white athrophies surrounding ulcer
pain from venous ulcers is worst ___
at night
arterial ulcers come from peripheral vascular disease (artherosclerosis, smoking, hypertension, diabetes all predisposing factors). Where is this most likely to affect?
LE - foot/toes/ankle
venous ulcers are shallow and wide, what about arterial ulcers? at what level of oxygen might an arterial ulcer be gangrenous?
small and deep - 12 mm Hg
how does the wound bed of a arterial ulcer differ from a venous ulcer?
arterial ulcer will have more fibrin than granulation, and less exudate and will be dry.
The surrounding area will have cold pale shiny skin with thinkened nails and absent pulse
will the pain from arterial ulcers go away with elevation of the leg?
no, it will get worse
what disease tends to cause peripheral neuropathy
diabetes
sensory neuropathy can lead to what?
repeated/continuous trauma
motor neuropathy can lead to what?
muscle atrophy - abnormal pressure points in gait on metatarsal heads, friction and pressure makes callous and possibly hematoma
with thinning of fat pad = ulceration, malus performans pedis
autonomic neuropathy can lead to what?
altered sweating and vascular responses = dry cracks and hot swollen feet which is perfect for bacteria and fungi
where are neuropathic ulcers found the most? What shapes?
bottom of the feet, small and deep
what type of wound infection is most common?
topical (ie impetigo)
what is the difference between a topical and local infection?
presence of swelling, redness larger than 2cm surrounding wound, surrounding tissue easily damaged as well as granulation tissue
what can one use to measure a wound?
cotton swabs and ruler, or use a tracing pad or the clock technique
what else is important to assess with peripheral neuropathy?
pressure sensitivity - use wire to see if they can feel at least 8/10 points on feet.
skin discolouration and temperature
capillary refill (should be 5s or less)
pulses
raise leg to 30 degrees - toes should stay same colour
what does the ankle brachial pressure index check? what other one can you use?
if it’s safe to use compression therapy, if enough blood to heal
- divide systolic pressure of ankle over arm or toe (TBI)
what ABI values indicate arterial insufficiency?
0.8-0.9 = mild insufficiency
0.5-0.7 = moderate, consult vascular surgery
less than 0.5 = severe, don’t do anything else to heal wound
what are three important factors to address in local wound care?
debridement, hydration, inflammation/infection
what can be done for treating the cause of venous ulcers? neuropathic?
compression modalities - venous
decrease WB - neuropathic
patient centered concerns should involve what?
education about foot hygiene, consults to other professionals
when should one not debride a wound?
- insufficient blood blow for healing
- dry gangrene
- stable eschar on the heels (protects)
- problems with coagulation that are not controlled
- irradiated tissue
- pyoderma gangrenosum
- if there is a non-breathable dressing on an infected wound + autolytic debridement
- presence of metal composites
- wound with vasculitis
what is the minimum amount of compression necessary in a preventative drug-store type stocking for helping prevent venous ulcers?
30-40 mm Hg
if a patient with venous ulcers has pain or lymphedema, which type of compression bandage are they more likely to prefer?
inelastic, 10-20 mm Hg which create compression when calf muscles contract
high compression bandages offer how much pressure?
20-40mm Hg
what are some situations where it’s good to be precautious about debridement?
- immunosuppressed patient or high risk of infection
- very young or old
- debridement that keeps macerated tissue moist
- enzymes less effective in dry environment
- diabetic ulcer
- mechanical debridement with pulsed flow more than 15lbs/square inch
what are three roles of fibrin
retains fluids
protects underlying cells
provides substances for coagulation
what pressures do mattresses need to be to be curative or preventative?
curative - less than 32mm Hg
preventative - 40-70mm Hg
what does the darco shoe do?
decrease wb on toe area during gait
what does compression do
improves venous return
reduction of edema
improved tissue perfusion
when should you not use compression?
arterial insufficiency
localized infection
thrombophlebitis (and 2 wks after)
local pressure hypersensitivity
pulmonary embolism or DVT
congestive heart failure
when using an ICP, how should the limb be positioned?
elevated
what are the parameters of using an ICP pump?
5-7x/week
30-60 min, with 3:1 on/off
compression of 40-60mm Hg - only use up to 0.8 ABI
how long should hydrotherapy be used for
a) pressure, cellulitis, or burns
b) arterial ulcers
c) venous and neuropathic ulcers
a) 10-20 minutes (15-20 for pressure ulcers actually)
b) 2-10min
c) 5-10min
when is hydrotherapy a good idea?
when there’s lots of crap on the wound
ie bacteria, foreign objects, exudate, topical creams, dead tissue
when is hydrotherapy a bad idea?
- wound is already clean or there is a healthy bed of granulation tissue
- arterial insufficiency (severe)
- DVT
- temperature discrimination impairment
- severe edema
- maceration tissue
- hemophilia
- unstable physically or mentally
- skin cancer
- first trimester pregnancy
- transmissible infection or infection from certain bacterias that cause incontinence or diarrhea
does the wound go into a bath with the dressing on?
yes
what should be done during the bath?
AROM
