Gangrene arises when a considerable mass of body tissue dies (necrosis). This may occur after an injury or infection, or in people suffering from any chronic health problem affecting blood circulation. The primary cause of gangrene is reduced blood supply to the affected tissues, which results in cell death. Diabetes and long-term smoking increase the risk of suffering from gangrene.
There are different types of gangrene with different symptoms. Two major types of gangrene exist:
Dry gangrene is caused by a reduction of blood flow through the arteries. It appears gradually and progresses slowly. In most people, the affected part does not become infected. In this type of gangrene, the tissue becomes cold and black, begins to dry, and eventually sloughs off. Dry gangrene is commonly seen in people with blockage of arteries (arteriosclerosis) resulting from increased cholesterol levels, diabetes, cigarette smoking, and genetic and other factors.
Wet or moist gangrene develops as a complication of an untreated infected wound. Swelling resulting from the bacterial infection causes a sudden stoppage of blood flow. Cessation of blood flow facilitates invasion of the muscles by the bacteria and multiplication of the bacteria because disease-fighting cells (white blood cells) cannot reach the affected part.
Gas gangrene is a type of wet gangrene caused by the bacteria known as Clostridia. Clostridia are a type of infection-causing bacteria that grow only in the absence of oxygen. As Clostridia grow, they produce poisonous toxins and gas; therefore, the condition is called gas gangrene.
Thee are also
Necrotizing fasciitis affects the deeper layers of the skin.
Noma is a gangrene of the face.
Fournier gangrene usually affects the male genitals and groin.
Gangrene Symptoms
Dry gangrene:
The affected area becomes cold and numb.
Initially, the affected area becomes red.
Then, it develops a brown discoloration.
Finally, it becomes black and shriveled.
Wet or moist gangrene:
The affected area becomes swollen and decays.
It is extremely painful.
Local oozing occurs.
It produces a foul-smelling odor.
It becomes black.
The affected person develops a fever.
Gas gangrene:
The wound is infected.
A brown-red or bloody discharge may ooze from the affected tissues.
Gas produced by Clostridia may produce a crackling sensation when the affected area is pressed.
It becomes swollen.
Pain in the affected area is severe.
The affected person develops fever, increased heart rate, and rapid breathing if the toxins spread into the bloodstream.
Treatment
People with gangrene require urgent assessment and treatment to prevent the spread of gangrene. Antibiotics and surgery are the primary treatments and have been proven very effective. Hospitalization is necessary for treatment.
Dry gangrene: Because the cause of dry gangrene is a lack of blood flow, restoring the blood supply is vital. Assessment by a vascular surgeon can help determine whether surgical intervention to restore blood supply would be beneficial.
Wet gangrene: Surgical debridement (removal of dead tissue) of the wound is performed, and intravenous antibiotics are administered to control the infection.
Gas gangrene: This condition needs to be treated aggressively because of the threat of the infection rapidly spreading via the bloodstream and damaging vital organs. The wound requires immediate debridement. Antibiotics are administered to the affected person.
Prevention
If tissue obtains good oxygenation by adequate arterial blood flow and does not become infected, then both dry and wet gangrene can be prevented. Consequently, avoiding tobacco use and avoiding external trauma like frostbite can help prevent gangrene. Perhaps the best way to prevent gangrene, especially in developed countries, is to keep patients with diabetes under good glucose control and to have them do frequent examinations of their feet for any signs of cuts, infection, or redness. Patients with diabetic neuropathy (for example, numbness in extremity) should do this daily.
If any wound or burn occurs, it should be treated immediately to prevent infection. This is especially important in people with diabetes, vasculitis, or a compromised immune system.
Some patients that notice coolness and redness of a local area (for example, toes, fingers) and get an angiogram that shows arterial blockage can have successful prevention of dry gangrene (and possibly wet gangrene) if the vascular surgeon can remove the clot or obstruction in the artery before local tissue dies.
