What is Gangrene ?

Gangrene is a medical term used to describe the death of an area of the body. It develops when the blood supply is cut off to the affected part as a result of various processes, such as blockage of blood vessels due to cholesterol and calcium deposition(Atherosclerosis), Cigarette smoking or Trauma. Gangrene can involve any part of the body; the most common sites include the toes, fingers, Feet, and hands.

Gangrene foot with loss of great toe

Angiogram demonstrating complete blood cut off in the left leg

Wet gangrene of the foot due to diabetes

Entire forefoot loss due to gangrene

Fast facts on gangrene

Here are some key points about gangrene.

  • Gangrene occurs due to lack of blood supply, and therefore oxygen, results in tissue death.
  • Gangrene is usually external, affecting the extremities, but it can also affect internal tissues.
  • Immediate attention by a skilled vascular surgeon is important to prevent further serious illness and death. This includes bypass procedures to restore your circulation and sometimes amputation in case of advanced gangrene .

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 (atherosclerosis) resulting from increased 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.

Dry gangrene left foot due to smoking

What Causes Gangrene?

The following conditions are risk factors for the development of gangrene:

  • Injury or trauma, such as a crush injury, a severe burn, or frostbite
  • Diseases that affect the circulation of blood, such as arteriosclerosis, Smoking, Diabetes, cholesterol deposition in your blood vessels.

Infection of wounds.

What Are the Symptoms Gangrene?

    • The affected limb becomes cold and numb.
    • The affected area becomes swollen and decays.
    • Associated with fever and pain.
    •  Foul-smelling Discharge from the wound.
    •  Black and shrivelled Limb.

When Should I Call the Doctor about Gangrene?

Consult a Vascular surgeon immediately if the following signs develop:

  • An area of the body turns blue or black.
  • A wound does not heal in seven to14 days.
  • Unexplained fever is persistent.
  • Pus  drains from the wound.
  • A foul-smelling odor discharges from the wound.


Gangrene is a limb and life threatening condition which warrants immediate medical attention.

If left untreated it can cause sepsis which can affect your kidneys, lungs and other organs.


Treatment depends on the type, location, and extent of diseased tissue.

Anyone with suspected symptoms of gangrene needs immediate medical attention, to reduce the risk of serious complication and death.

Treatment may involve the following emergency measures:

  • Restoring Blood Supply
  • Intravenous antibiotics, Blood transfusion.
  • surgical removal of dead tissue, including amputation of an extremity or a limb to halt the wider spread
  • Reconstructive surgery like skin grafting, Flaps and other techniques.

Restoring blood flow

In some cases, surgery may be carried out to restore the blood flow to the affected area. The main techniques used to achieve this are:

  • Bypass surgery– where the surgeon redirects the flow of blood and bypasses the blockage by connecting (grafting) one of your veins to a healthy part of an artery
  • Angioplasty– where a tiny balloon is placed into a narrow or blocked artery and is inflated to open up the vessel; a small metal tube, known as a stent, may also be inserted into the artery to help keep it open

Research suggests that both techniques are equally effective in restoring blood flow and preventing the need for amputation in the short-term. An angioplasty has the advantage of having a faster recovery time than bypass surgery, although it may not be as effective in the long-term as bypass surgery.

Removing dead tissue

Surgery to cut out the dead tissue, known as debridement, is often necessary to prevent the gangrene from spreading and to allow the surrounding healthy tissue to heal.


In severe cases of gangrene, where a whole body part, such as a finger, toe, or limb, is affected and debridement is unlikely to help, amputation may be considered.

Amputation can prevent gangrene spreading to other parts of the body and can be used to remove a severely damaged limb so an artificial (prosthetic) limb can be fitted.

Unless immediate emergency treatment is needed, a decision to amputate will only be made after a full discussion between you and the health professionals treating you.

Treating infection

Gangrene that’s caused by an infection can usually be treated with antibiotics, which can be given as tablets or injections.

Injections are usually necessary if you need surgery or you have a severe infection. Injecting antibiotics directly into a vein allows larger doses to be given and means that they’re more likely to reach the affected area.

Reconstructive surgery

Reconstructive surgery using a skin graft may be used to cover the area of skin damaged by gangrene.

During a skin graft, the surgeon will remove healthy skin from another part of your body (usually a part that would be covered by clothing), and reconnect it over the damaged area.

Gangrene foot with black toe