Gangrene: Definition, Symptoms, Causes And Treatment

Gangrene is a form of necrosis of tissue with superadded putrefaction.

Gangrene Etiology

In gangrene, the organ involved is pale, gray, purple, and brownish-black. This is due to the disintegration of hemoglobin to sulfide
Pulse is absent.
There is a loss of sensation and function
There is the presence of a line of demarcation between vital and dead tissue
. A band of hyperemia and hyperesthesia is present along with a developmental layer of granulation tissue.

Dry Gangrene is a condition that results when one or more arteries become obstructed.
In this gangrene, the tissue slowly dies because of inadequate or no blood supply.
Dry Gangrene happens mostly in the extremities and it occurs in people with diabetes or arteriosclerosis.
Dry Gangrene can also develop after prolonged exposure to freezing temperatures.
In dry gangrene tissue fist becomes bluish and the patient feels cold to the touch, As time progresses, a line of demarcation appears between the healthy and devitalized tissue, which becomes dry and dark black.
Eventually, there may be a separation of the dead tissue from the living tissue; with spontaneous amputation (autoamputation) of the involved extremity.
Treatment of this type of gangrene is aimed at improving circulation, and revascularization (i.e. restoration of blood to flow) to the affected area. This may be accomplished with drugs or through the surgical removal of the obstruction.

Wet gangrene is gangrene that develops as a complication of an untreated infected wound, caused by a certain bacterial infection.
The tissue is infected by saprogenic microorganisms (C.perfringens, fusiformis, etc.) which cause tissue to swell and produce a fetid smell.
This gangrene develops rapidly due to blockage of venous and/or arterial blood flow.
In this affected part is saturated with stagnant blood, which promotes the rapid growth of bacteria.
Toxic products formed by bacteria are absorbed causing the systemic manifestation of septicemia and finally death.
Wet gangrene occurs in naturally moist tissue and organs such as the mouth, bowel, lungs, cervix, and vulva.
Bedsores occurring on body parts such as the sacrum, buttocks, and heels—although not necessarily moist areas are also categorized as wet gangrene infections.
The affected part is edematous, soft, putrid, rotten, and dark. The darkness in wet gangrene occurs due to the same mechanism as in dry gangrene.
Administration of antibiotics and sometimes the surgical removal of the dead tissue to keep the infection from spreading is the treatment.

Gas gangrene is a bacterial infection that produces gas within tissues.
Gas Gangrene is caused by bacterial exotoxins produced by Clostridium perfringens which are mostly found in soil and other anaerobes (e.g. Bacteroides and anaerobic streptococci).
The infection spreads rapidly as the gases produced by bacteria expand and infiltrate healthy tissue in the vicinity.
After an incubation period of one to four or five days, the affected tissue is swollen, painful, and cold.
A watery, brownish, foul-smelling fluid drains from the wound and little bubbles of gas develop in the tissues.
Gas gangrene can cause necrosis, gas production, and sepsis. Progression to toxemia and shock is often very rapid.
Gas gangrene is often treated with the antitoxin for Clostridium. In several cases. amputation may have to be used to keep the infection under control.
Severe cases have been treated by keeping the patient in an oxygen-rich atmosphere, as in a hyperbaric chamber.

Question 2. Enumerate the differences between dry and wet gangrene.

Answer.

Arterial Diseases Enumerate diffrences between dry and wet gangrene.

Defie gangrene. Describe various causes of gangrene and management of diabetic gangrene foot.

Answer. Gangrene is the death of body tissue associated with loss of vascular supply and followed by bacterial invasion and putrefaction.

Secondary to arterial occlusion like atherosclerosis, emboli, diabetes, and Raynaud’s disease.
Infective: Boil, carbuncle, gas gangrene, Fournier’s gangrene, cancrum oris
Traumatic: Either direct trauma or indirect trauma
Physical: Burns, scalds, frostbite, chemicals, irradiation, electrical
Venous gangrene.

The foot can only be saved if a good blood supply is present.

Antibiotics should be started based on culture and sensitivity tests.
Regular dressings should be given to the patient
Drugs such as vasodilators, pentoxifylline, dipyridamole, and low-dose aspirin are given.
Diabetes is controlled by insulin
The diet should be controlled
Surgical debridement of the wound is carried out.

Amputations of diabetic foot should be done occasionally.

The level of amputation is decided based on skin changes, temperature, line of demarcation, and Doppler study.
Below knee, amputation is done, in this BK prosthesis is fitted better and also the movements of the knee joint are retained.
In the above-knee amputation range of movements is less, limb is present and requires third support to walk.

Gangrene limb-Saving Method

Drugs such as antibiotics, vasodilators, small doses of aspirin, and paraxylene are started.
Care of feet and toes: Part ofthe feet or toe should be kept dry.

Any injury has to be avoided
Proper footwear is advised for the patient
Pressure areas should be protected.
If pus is present, it has to be drained.
The limb should not be warmed.
Diabetes should be controlled.
Surgeries such as omentoplasty, profunda plasty, and arterial bypass graft are done to improve limb perfusion.

Gangrene Lifesaving Procedures

Amputations can be done as a lifesaving procedure.

Below-knee amputation is a better option as the fi of the prosthesis is better and movements of the knee joint are retained.
In above-knee amputation range of movement is less and third support is required to walk.