Gangrene

2. Gangrene:
 It is a form of necrosis with superadded
putrification (infection of dead tissue).
 there are 2 main types: dry gangrene
wet gangrene
there is a variant form of wet gangrene , called as
gas gangrene.

3. Dry gangrene:
 It initiates from distal parts.
 Dry gangrene is mainly due to arterial occlusion.
 limited putrefaction and bacteria fail to survive.
 spreads slowly until it reaches the point where the
blood supply is adequate .
 Clinical features: The affected part is dry, cold,
shrunken and dark reddish black
resembling mummified flesh.
eventual falling off of the gangrenous tissue if it is not
removed surgically, also called autoamputation

5. Wet gangrene:
 Wet gangrene occurs in naturally moist tissue and organs
such as the mouth, bowel, lungs, cervix, and vulva.
 It is characterized by numerous bacteria and has a poor
prognosis (compared to dry gangrene) due to septicaemia .
 develops rapidly and is due to blockage of venous (mainly)
and/or arterial blood flow.
 The affected part is saturated with stagnant blood, which
promotes the rapid growth of bacteria.
 The toxic products formed by bacteria are absorbed,
causing systemic manifestation of septicaemia and finally
death.
 Clinical features: The affected part is oedematous , soft,
putrid, rotten and dark . In wet gangrene, tissue swell and
emit a fetid smell and pain is there.

7. Gas gangrene:
 Also called myonecrosis (destruction or death of
muscle tissue) is a type of wet gangrene, which is
mostly caused by bacterial infections.
 These bacteria are anaerobic and they produce many
gasses and poisonous toxins. They inhibit the
gastrointestinal, respiratory and female genital tracts,
and attack a recent surgical wound.
 It is caused by deep wound and crushing injuries and
can also be caused by frostbite, diabetes mellitus and
cancer.
 Clinical feature : pus is brown, gas bubbles under the
skin (crepitations) , skin colour -red initially ,then
turns brown and black, foul odour ,high grade fever.

10. Causes
 Gangrene happens when a body part loses its blood
supply. This may happen from injury, burn, an
infection or other causes. higher risk for gangrene if :
 A serious injury
 Blood vessel disease (such as arteriosclerosis, also
called hardening of the arteries, in arms or legs)
Burger’s disease (thromboangitis obliterans) ,
Raynaud’s disease.
 Diabetes
 Suppressed immune system (for example, from HIV or
chemotherapy)
 Surgery
 Severe frostbite

11. Examination:
 Blood test results show an increase in the number
of white blood cells in persons with wet gangrene.
 A sample of pus is examined to identify the
bacteria causing the infection.
 An x-ray film may be performed to examine the
affected tissue for the presence of gas bubbles.
 Imaging studies, including a CT scan and/or MRI,
can help determine the extent of damage to the
tissues and the amount of gas present.
 In people with dry gangrene, an arteriogram may
be performed to visualize any obstruction in the
artery which supplies blood to the affected part.

13. Treatment: medical
 consists of drugs to improve circulation or surgery
to bypass blocked arteries(dry gangrene)
 but if tissue is already dead, affected area will be
removed surgically (debridement), if underlying
muscle and bone are also dead, amputation will
be necessary
 any remaining bacteria are also destroyed by
antibiotics(penicillin), antiserum or hyperbaric
oxygen treatment. Pain relievers , Anticoagulants
(heparin) are also given.

15. Physiotherapy:
 Those who do undergo excision of the gangrene
may require physical and occupational therapy
prior to discharge from the hospital in order to
increase endurance. Physical therapy typically
includes
 learning to care for the residual limb
 performing stretches
 weight-bearing exercises to increase mobility.

16. Physiotherapy: toes amputed
 relearn the mechanics
of walking as a result of
decreased stability.
Individuals learn to
walk with a cane or may
require a prosthesis
that fits over the foot to
increase stability.

17. In foot or lower limb amputation:
 Individuals begin walking in
a set of parallel bars and
then advance to skills such
as walking and negotiating
stairs. Some individuals may
require a cane or crutches to
increase stability, even with
the prosthetic limb.
 Others, such as individuals
in poor overall health or
those who have had an
above-knee amputation,
may require a wheelchair for
mobility.

18. One or more fingers amputed:
 may require occupational therapy to relearn
tasks such as writing, grasping objects, and
dressing.
Those who lose part of an arm:
learn to bear weight through the residual limb
using exercises such as wall push-ups that allow
more functional return to the residual limb.
Individuals use the grasping mechanisms of a
prosthetic arm to perform activities such as
dressing and driving.

20. Above elbow amputation:
 In this case, an individual attends occupational
therapy to learn how to compensate for the
amputated limb by relearning to perform daily
tasks with one hand.
 Individuals with an amputation of the dominant
hand relearn handwriting tasks with the
nondominant hand.

21. Complications of gangrene:
 Blood poisoning.
 Shock.
 DIC (disseminated intravascular coagulation), a
blood-clotting disorder.
 Limb amputation to prevent death.

22. Prevention:
 Gangrene may be prevented if it is treated before
the tissue damage is irreversible. Wounds should
be treated properly and watched carefully for
signs of infection (such as spreading redness,
swelling, or drainage) or failure to heal.
 People with diabetes or blood vessel disease
should routinely examine their feet for any signs
of injury, infection, or change in skin colour and
seek care as needed.

23. Prognosis:
 Usually curable in the early stages with antibiotic
treatment and surgery to remove dead tissue.
Without treatment, gangrene may lead to fatal
infection