What Is Gangrene?
Gangrene happens when tissues in your body die after a loss of blood flow caused by illness, injury, or infection. It usually happens in extremities like fingers, toes, and limbs, but you can also get gangrene in your organs and muscles. There are different types of gangrene, and all of them need medical care right away.
What Are the Gangrene Risk Factors?
Any condition that decreases your blood flow increases your chances of getting gangrene, including:
- Narrowed arteries (atherosclerosis)
- Peripheral artery disease
- Trauma or serious injury
- Serious frostbite
- Weakened immune system
What Are the Types of Gangrene?
There are two main types of gangrene:
Dry gangrene: This is more common in people who have vascular disease, diabetes, and autoimmune diseases. It usually affects your hands and feet. It happens when something -- often, poor circulation -- blocks blood flow to a certain area. As your tissue dries up, it changes color. It may be brown to purplish-blue to black. The tissue often falls off. Unlike with other types of gangrene, you typically don’t have an infection. But dry gangrene can lead to wet gangrene if it becomes infected.
Wet gangrene: This type almost always involves an infection. Burns or trauma in which a body part is crushed or squeezed can quickly cut off blood supply to the area, killing tissue and raising the odds of infection. The tissue swells and blisters; it’s called "wet" because it causes pus. Infection from wet gangrene can spread swiftly around your body.
Types of wet gangrene include:
Gas gangrene: Gas gangrene is rare but especially dangerous. It happens when you get an infection deep inside your body, such as inside muscles or organs, usually because of trauma. Bacteria called clostridia release dangerous toxins or poisons, along with gas that can be trapped in your tissue. Your skin may become pale and gray and make a crackling sound when pressed. Without treatment, gas gangrene can be deadly within 48 hours.
Fournier’s gangrene: Also a rare condition, Fournier’s gangrene is caused by an infection in your genital area. It affects men more often than women. If the infection gets into your bloodstream, a condition called sepsis, it can be life-threatening.
Progressive bacterial synergistic gangrene (Meleney’s gangrene): This type usually causes painful lesions on your skin 1 to 2 weeks after surgery or minor trauma. It’s also rare.
What Are the Symptoms of Gangrene?
Dry gangrene symptoms include:
- Shriveled skin that changes from blue to black and eventually comes off
- Cold, numb skin
Symptoms of wet gangrene include:
- Swelling and pain
- Fever and feeling unwell
- Red, brown, purple, blue, greenish-black, or black skin
- Blisters or sores with a bad-smelling discharge (pus)
- A crackling noise when you press on the affected area
- Thin, shiny, or hairless skin
- A line between healthy and damaged skin
Internal gangrene causes severe pain in the affected area. For example, if you have gangrene in your appendix or colon, you’d probably have belly pain. Internal gangrene can also cause a fever -- a condition that requires emergency surgery.
How Do You Diagnose Gangrene?
Your doctor will ask about your symptoms and medical history. You may have:
- Blood tests. These look for bacteria or check for signs of infection, like more white blood cells than usual.
- Imaging tests. CT and MRI tests tell your doctor whether your gangrene has spread and if gas has built up in your tissues. In an arteriogram, your doctor injects dye into your blood and then takes an X-ray to check blood flow and look for blocked arteries.
- Cultures. Your doctor might take a sample of blood, fluid, or tissue, and look at it under a microscope for signs of bacteria or tissue death.
- Surgery. This can confirm internal gangrene or tell your doctor whether gangrene has spread.
What Are Possible Gangrene Complications?
If an infection gets into your blood, you may get sepsis and go into septic shock. This needs treatment right away. Symptoms include:
How Do You Treat Gangrene?
Treatment for all forms of gangrene involves removing dead tissue, treating and stopping the spread of infection, and treating the condition that caused the gangrene. The sooner you get treatment, the more likely you are to recover.
Your treatment depends on the type of gangrene and may include:
Surgery. Also called debridement, this is usually the first-line treatment. Your doctor removes dead tissue to keep the infection from spreading. They might need to remove an affected limb, finger, or toe (amputation).
Maggot therapy. Believe it or not, maggots still play a role in modern medicine. They’re a nonsurgical way to remove dead tissue. Your doctor puts maggots from fly larvae (specially bred in a lab so they’re sterile) on your wound, where they eat dead and infected tissue without hurting healthy tissue. They also help fight infection and speed healing by releasing chemicals that kill bacteria.
Antibiotics. You might get antibiotics through a needle (called intravenous, or IV) to treat or prevent infection.
Oxygen therapy. Hyperbaric oxygen therapy can treat wet gangrene or ulcers related to diabetes or peripheral artery disease. You spend time in a special chamber filled with oxygen at a higher pressure than oxygen found in the outside air. Experts think this high level of oxygen fills your blood and speeds tissue healing. Oxygen therapy may also slow the growth of bacteria.
So that you don’t get gangrene again, your doctor will need to find out what’s blocking your blood supply and treat that condition. You might need vascular surgery, such as bypass surgery or angioplasty, to restore blood flow. You might also take medication to prevent blood clots.
How Can You Prevent Gangrene?
The best ways to prevent gangrene are to:
- Manage your health conditions. If you have diabetes, keep your blood sugar levels under control. Check your hands, feet, and legs regularly for signs of injury, slow wound healing, or other skin problems. Follow your doctor’s advice on living with other conditions that affect your blood flow like peripheral artery disease or Raynaud’s phenomenon.
- Watch your wounds. Get medical care right away if you see signs of infection.
- Don’t smoke.Tobacco can damage your blood vessels.
- Keep a healthy weight. Extra pounds can put pressure on your arteries, blocking blood flow.
- Stay warm. Frostbite also blocks blood flow and can lead to gangrene.
- Protect your feet if you have diabetes.
- Protect your feet if you have peripheral vascular disease.
- Talk to your doctor if you have swelling in your legs that makes it hard to put shoes or socks on.