Gangrene Flashcards
What is gangrene?
A severe condition of localized tissue necrosis
Gangrene can lead to significant complications if not treated promptly.
What are the two main types of gangrene?
Dry gangrene and wet gangrene
Each type has distinct causes and clinical features.
What causes dry gangrene?
Arterial occlusion leading to ischaemia
The most common cause is peripheral arterial disease.
List the primary underlying causes of dry gangrene.
- Peripheral arterial disease
- Diabetes mellitus
- Vasculitis
These conditions can lead to decreased blood flow.
What are the clinical features of dry gangrene?
- Dry, shriveled, dark brown or black
- Clear line of demarcation between viable and dead tissue
These features help in differentiating it from other conditions.
What results in wet gangrene?
Infection causing tissue death due to blockage in venous outflow or lymphatic drainage
Wet gangrene is often more acute and severe.
Where is wet gangrene most commonly found?
Areas with rich blood supply like internal organs or skin folds
This makes it more prevalent in certain anatomical locations.
List the risk factors for wet gangrene.
- Chronic limb ischaemia
- Surgical wounds or trauma
- Immunosuppression (e.g. HIV/AIDs)
- Severe burns or frostbite
These factors can predispose individuals to infection.
What are the clinical features of wet gangrene?
- Swollen
- Blistered
- Foul smelling
These signs are critical for diagnosis.
What is gas gangrene?
Deep wound infection with gas-producing bacteria
Caused by bacteria like Clostridium perfringens.
What are the clinical features of gas gangrene?
- Gas bubbles in necrotic tissue on radiograph
- Severe pain at site
- Signs of sepsis
These features indicate a serious condition requiring immediate treatment.
What is necrotising fasciitis?
Rapidly progressing infection of subcutaneous tissues and fascia
It requires immediate surgical intervention.
What is Fournier’s gangrene?
Necrotising fasciitis of genitalia or perineum
This condition is a surgical emergency.
What is Meleney’s gangrene?
Post-operative progressive bacterial gangrene
It occurs after surgery and can lead to severe complications.
List the local signs of gangrene.
- Discoloration (red → brown → black)
- Distinct malodour
- Swelling
- Tenderness on palpation
- Sensory changes (numbness or cold)
- Tissue loss (exposing bones or tendons)
These signs help in the initial assessment of the condition.
What are the systemic signs of gangrene?
- Fever and malaise
- Hypotension (if septic shock)
- Multisystem involvement
Systemic signs indicate a more severe infection.
What lab tests are used in the investigation of gangrene?
- Blood cultures
- Tissue cultures
- FBC, U&Es, LFTs, coagulation profile
- CRP, ESR
These tests help identify the causative organisms and assess the patient’s condition.
What imaging technique can be used to investigate gas gangrene?
X-ray
X-rays may show gas formation in tissues.
What are the management strategies for gangrene?
- Surgical debridement
- Antibiotic therapy (broad-spectrum first)
- Hyperbaric oxygen therapy
These strategies aim to limit the spread of infection and promote healing.
What complications can arise from gangrene?
- Sepsis
- Chronic pain
- Limb loss
- Fistulas
These complications can significantly affect patient outcomes.
