Treatment for gangrene involves removing the affected tissue, preventing infection or treating any existing infection, and treating the problem that led to gangrene developing.
For example, if gangrene is caused by a poor blood supply, surgery may be used to repair damaged blood vessels.
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 some cases, it may be possible to use 'maggot therapy' (‘biosurgery’) instead of conventional surgery to remove the dead tissue.
Certain types of maggot are ideal for this because they feed on dead and infected tissue but leave healthy tissue alone. They also help fight infection by releasing substances that kill bacteria and stimulate the healing process.
Maggots used for maggot therapy are specially bred in a laboratory using eggs that have been treated to remove bacteria. During maggot therapy, the tiny maggots are put on to the wound and covered with gauze, under a firm dressing. After a few days, the dressing is cut away and the maggots are removed.
A number of medical studies have shown maggot therapy can achieve more effective results than surgical debridement. However, because of the nature of this type of treatment, many people are reluctant to try it.
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 treatment is needed in an emergency, a decision to amputate will only be made after a full discussion between you and the health professionals treating you.
Read more about amputation.
If your gangrene is caused by an infection, you will usually be treated with antibiotic medication. These medications can be given as tablets or injections.
Injections are usually necessary if having surgery or if you have a severe infection. They allow bigger doses to be given and they are more likely to reach the affected area.
To counter the effects of infection and accelerate the healing process, you will also need fluids and nutrients into a vein (intravenous fluids) and may need blood transfusions.
Restoring the 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.
Hyperbaric oxygen therapy
An alternative treatment for some forms of gangrene is hyperbaric oxygen therapy.
During this treatment, you sit or lie down in a specially designed chamber filled with pressurised air. A plastic hood that provides pure oxygen for you to inhale is then placed over your head.
This treatment results in high levels of oxygen diffusing into your bloodstream and getting to the affected areas (even those with a poor blood supply), which speeds up healing.
If you have gangrene caused by a bacterial infection, the oxygen can also stop some types of bacteria (particularly the type responsible for gas gangrene) producing the toxins that allow the infection to spread, preventing further tissue damage.
Hyperbaric oxygen therapy has proved effective in treating gangrene resulting from infected diabetic foot ulcers, reducing the risk of amputation.
However, evidence relating to the effectiveness of hyperbaric oxygen therapy in treating other types of gangrene is limited and further research is required. Hyperbaric oxygen therapy is also currently not widely available in the UK.
Reconstructive surgery using a skin graft (skin taken from elsewhere on the body) 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 then reconnect it over the damaged area.
See plastic surgery techniques for more information about skin grafts.