Gas gangrene (Clostridial
Myonecrosis)
Acute necrotic condition of the soft tissue that lead to death and
deterioration of a part of the body, caused by interference with blood
supply and infection.
Causes: gas forming anaerobic bacteria C. perfringens which
grows in tissue that have low oxygen tension caused by trauma or
ischemia
- Minor injuries in the immunocompromised patients (diabetes mellitus)
- Any kind of surgery (traumatic or surgical interruption of blood
supply)
- Deep contamination of wound due to foreign body, soft tissue trauma
and bone fracture
C. perfringens releases Alpha-exotoxin that produces lethal gas, which
is rapidly spreading to the muscle causing massive tissue swelling and
necrosis.
Clinical symptoms: swollen painful wound with gas bubble in the
drainage, felt as crepitus in the soft tissue as well as systemic
toxemia and failure of whole body (fever, renal damage and
cardiotoxicity).
Clinical application of HBO:
Life-saving –less surgery needs to be performed especially in older and
very ill patients
Limb and tissue -saving-no need for major amputation
- Reduces infection by inhibition of alpha-toxin
(bacteriostatic effect-formation of oxygen free radicals that prevent
further alpha-toxin production)
- Enhances the effect of some antibiotics by helping in
better penetration
- Provides faster and clear demarcation between dead and
healthy tissue
- Promotes wound healing by restoration in blood supply
- Reduces edema by vasoconstriction
- Improves osteoclastic activity (removing necrotic bone)
