Leg ulcers Flashcards
what is a leg ulcer
full thickness skin loss on the leg or foot
what are acute ulcers
may occur after trauma or surgery, normally heal within 4 weeks
what is a chronic ulcer?
ulcer lasting >4 weeks
commonest underlying causes of chronic ulcer?
venous and/ or arterial disease, neuropathy and diabetes
most common type of leg ulcer?
venous (70-80%)
aka stasis ulcer
12-20% of leg ulcers are ___
mixed (arterial and venous)
aetiology of venous ulcers?
multifactorial
- venous insufficiency
- high venous pressure
- oedema within the surrounding tissue
risk factors
- elderly age
- varicose veins
- previous DVT
- phlebitis
- immobility
- obesity
pathophysiology of venous ulcers?
poor functioning of one-way valves in veins of lower legs > venous stasis and pooling > venous HTN > leakage of fluid from the venous vessels into the surrounding tissue causes oedema which contributes to lipodermatosclerosis > slows venous flow further, depriving area of oxygen and nutrients > tissue cells become necrotic and die > ulceration with poor healing
what is lipodermatosclerosis?
involves tissue induration, deposition of haemosiderin, fibrosis and atrophy blanche
venous ulcers
1) onset
2) location
3) appearance
4) symptoms/ signs
1) insidious
2) ‘gaiter’ region: from mid-calf to just below the malleoli
3) large circumference with irregular border, shallow ulcer, base has granulating tissue. Associated signs of venous disease: varicose veins, venous eczema, stasis dermatitis, hyperpigmentation (haemosiderin deposition)
4) little/ no pain (relieved by elevation). Lipodermatosclerosis. Atrophe blanche
what is atrophe blanche
Telangiectasia appears where there are areas of venous congestion. When the capillaries can no longer cope with this high pressure they collapse, resulting in white areas of avascular tissue.
T/F: diagnosis of venous leg ulcers is usually clinical
true
should also investigate for any underlying cause (usually only found if arterial/ mixed) - diabetes, vasculitis, RA etc
ABPI values?
0.9-1.2 = Normal.
0.8-0.9 = Mild arterial disease.
0.5-0.8 = Moderate
<0.5 = Severe (refer urgently to vascular surgery)
what Ix to do if ulcer is mixed?
doppler USS
when to swab an ulcer?
if +ve should you treat with Abx?
if painful, growing, malodorous, exudate
swabs often grow commensals- only treat if infected clinically
Rx of venous ulcers?
- pain control
- underlying cause
- non-adherent dressings
- de-sloughing agent
- compression bandaging (4 layers)
purpose of non-adherent dressings in venous ulcers?
helps create optimum environment for ulcer healing (pH, temp, anti-microbial)
examples of de-sloughing agents?
honey, hydrogel
how does doppler US help guide compression bandaging treatment for venous ulcers?
Doppler score >0.8 = Graduated compression bandage.
Score 0.5-0.8 = Reduced / light compression bandage.
Score <0.5 = Compression bandage contraindicated.
what causes an arterial leg ulcer?
reduced blood flow within the lower leg, most commonly due to atherosclerosis
risk factors for arterial ulcers?
IHD Previous CVA or TIA Diabetes mellitus Peripheral vascular disease Obesity Immobility Hypertension Smoking
how do arterial leg ulcers form?
atherosclerosis > narrowing of lower leg arteries > thickening of arterial walls mean nutrients and oxygen within blood can’t be sufficiently delivered to the tissues > cell necrosis and tissue breakdown
arterial ulcers are typically located more PROXIMALLY/ DISTALLY in lower leg
distally (dorsum of foot/ toes)