Gangrene and Necrotising Fasciitis Flashcards
Define Gangrene?
Tissue necrosis, either wet with superimposed infection, dry or gas gangrene
Define Necrotising Fasciitis?
A life-threatening infection that spreads rapidly across fascial planes
What is the aetiology of Gangrene?
Tissue Ischaemia and Infarction
Physical Trauma
Thermal Injury
What is Gas Gangrene caused by?
Clostridia Perfringens
What is the aetiology of Necrotising Fasciitis?
Usually polymicrobial involving streptococci, staphylococci, bacterioides and coliforms
What are the risk factors for Gangrene and Necrotising Fascitis?
Diabetes Peripheral Vascular Disease Leg Ulcers Malignancy Immunosuppression Steroid Use Puncture/surgical wounds
What is the epidemiology of Gangrene and Necrotising Fascitis?
Gangrene - Relatively common
Necrotising Fasciitis and Gas Gangrene- Rare
What are the presenting symptoms of Gangrene?
Pain
Discolouration of affected area
Often affects extremeties or areas subject to high pressure
What are the presenting symptoms of Necrotising Fasciitis?
Pain - often seems severe and out of proportion to the apparent physical signs Predisposing event (e.g. trauma, ulcer, surgery)
What are the signs of gangrene on examination?
Painful area = erythematous region around gangrenous tissue
What colour is gangrenous tissue generally?
Black because of Hb break down products
What are the signs of Wet Gangrene?
Tissue becomes boggy with associated pus and a strong odour caused by the activity of anaerobes
What are the signs of Gas Gangrene?
Spreading infection and destruction of tissues causing overlying oedema, discolouration and crepitus (due to gas formation by the infection)
What are the signs of Necrotising Fasciitis?
Area of erythema and oedema
Haemorrhagic blisters may be present
Signs of Systemic Inflammatory Response and Sepsis
What are the signs of Systemic Inflammatory Response and Sepsis?
High/low temperature
Tachypnoea
Hypotension
