Gangrene

Gangrene is a medical emergency in which blood stops flowing to a specific part of your body, and tissues in that area die. Gangrene can develop anywhere in your body, but it often starts in a foot or hand.

Gangrene always involves tissue death, but it doesn’t always involve an infection. A gangrene infection means bacteria are growing in the affected area. Without prompt treatment, gangrene (with or without an infection) can lead to serious complications or death. Possible treatments include antibiotics, hyperbaric oxygen therapy, and surgery to remove dead tissue and improve blood flow to the affected body part.

The main signs of gangrene include changes to your skin color and texture. Your skin may initially turn pale before looking reddish, then brown, and then finally purple or greenish black. Your skin may also feel firm, cool and/or tender to the touch, and you may notice blisters that ooze. The affected area may be very painful or else numb.

Seek medical care immediately if you think you have gangrene. Prompt treatment, including medications and procedures, can save your limb and your life.

Types of gangrene

There are several types:

• Dry gangrene: This is when blood can’t reach a certain area of your body, but there’s no infection. Your skin will feel dry to the touch (no open blisters or pus). This type, which may develop slowly, usually affects people who have peripheral artery disease (PAD) or diabetes. Treating PAD early, before it gets severe, and managing diabetes can help you avoid dry gangrene.
• Wet gangrene: This means there’s disrupted blood flow along with a bacterial infection. Blisters that release pus (the “wet” factor) form on your skin. You may notice fluid drainage and a foul smell coming from your skin. Wet gangrene can occur in response to frostbite, injuries or severe burns. It spreads quickly to nearby tissues. You need immediate treatment because it can be fatal.
• Gas gangrene: This bacterial infection destroys your soft tissues and blood cells. Bacteria quickly multiply in your muscle tissue, forming toxins and releasing gas. The infection spreads fast and can become life-threatening within hours of symptoms starting. Traumatic injury is the most common cause of this type of gangrene.
• Fournier’s gangrene: This is a rare, severe bacterial infection that affects the genital area. It’s a type of flesh-eating disease that affects males more often than females. It occurs when bacteria enter your genital or rectal area due to causes such as a UTI, an abscess or a bug bite. Your risk for this type of gangrene is significantly elevated if you have poorly managed diabetes.
• Internal gangrene: This is blocked blood flow to internal organs. Affected organs may include your gallbladder, intestines or appendix. A gangrenous gallbladder is a serious complication of chronic cholecystitis, where continued swelling leads to tissue death.

Symptoms of gangrene

Gangrene symptoms vary by type and may include:

• Changes in skin color (red, purple, green or black)
• Changes in how your skin feels (firm, cool and/or tender to the touch)
• Crackling sound when you press on your skin, which means there’s gas buildup underneath
• Fast breathing and heart rate
• Feeling very anxious
• Flu-like symptoms, like fever, sweating, chills and vomiting
• Severe pain or a loss of feeling
• Sores and blisters that release blood or foul-smelling pus
• Swelling of the affected area

What does gangrene look like?

Gangrene causes skin color changes that may occur in stages:

1. At first, your skin may look paler than usual due to lack of blood flow.
2. Then, it may turn red or reddish in color.
3. It may then turn brown before changing to purple or greenish black.

It may be more difficult to see these color changes if you have a darker skin tone.

If there’s an infection, you’ll notice sores or blisters with smelly fluid coming out.

Gangrene causes

Lack of blood flow to a specific part of your body causes gangrene. Blood delivers oxygen, nutrients and antibodies to your tissues. When your tissues don’t receive blood, they start to die.

Causes of blocked blood flow include:

• Medical conditions, like peripheral artery disease, that affect your circulation
• Infections in your tissue
• Severe, deep wounds, especially ones that affect muscle
• Surgical complications (rare)

Risk factors

You face an increased risk of gangrene if you have a condition that affects your blood vessels. Examples include:

• Buerger’s disease: Inflammation of blood vessels in your limbs leads to blood clots that block blood flow.
• Diabetes: This condition damages your nerves and blood vessels. Diabetes also causes wounds, including diabetes-related foot ulcers, to heal more slowly. Slow-healing wounds face a higher risk of infection.
• Peripheral artery disease (PAD): Plaque buildup in your arteries prevents enough blood from reaching your legs, feet, arms or hands.
• Popliteal artery entrapment syndrome: Your calf muscle squeezes your popliteal artery. This limits blood flow to your lower leg during physical activity.
• Raynaud’s syndrome: Cold temperatures affect the blood vessels in your fingers and toes. Your blood vessels narrow, limiting blood flow.
• Vasculitis: Inflammation of your blood vessels interferes with blood flow.

You also face a higher risk of gangrene if you have:

• A traumatic injury
• A weakened immune system
• Severe tissue damage from frostbite or burns

If you have any risk factors, see your provider for regular checkups and keep all your follow-up appointments. Your provider will tell you what you can do at home to lower your risk of gangrene — like taking good care of your feet and tending to wounds.

Ways to reduce your risk

If you have PAD or diabetes, you can reduce your risk of developing gangrene by:

• Eating a heart-healthy diet that’s low in saturated fat and cholesterol
• Exercising regularly, following your provider’s guidance
• Keeping your blood glucose levels within the normal range
• Avoiding all tobacco products
• Taking extra good care of your feet
• Regularly checking your feet and legs for signs of injury or skin breakdown

Complications of gangrene

Gangrene is serious and can be life-threatening. It may lead to:

• Infection that spreads to other tissues or organs
• Loss of a body part, like a finger, toe, hand or foot
• Sepsis and septic shock
• Organ failure

Gangrene is sometimes fatal.

How doctors diagnose this condition

See a healthcare provider right away if you think you have gangrene. They will:

• Ask about your medical history and current conditions
• Ask about any recent injuries
• Carefully evaluate the affected area of your body
• Run tests to learn more

Tests you may need include:

• Blood tests to check for infection
• Bacterial culture tests to determine the bacteria involved and the best antibiotic to treat the infection (if needed)
• Imaging tests, like X-rays, CT scans and MRIs, to confirm the diagnosis and assess spread
• Tests that check blood flow, like an ankle-brachial index

These tests help your provider learn what’s blocking blood flow, whether there’s an infection and the extent of tissue damage. All this information helps them plan treatment.

How is gangrene treated?

The goals of gangrene treatment are to:

• Remove dead or infected tissue from your body.
• Prevent or treat infection to keep gangrene from spreading.
• Help your blood flow better.

There are several options for gangrene treatment, including medications and procedures. Your provider will choose the best method or combination of methods for you, depending on the cause of your condition and how far it has progressed.

Antibiotics

When a bacterial infection causes gangrene, you need antibiotics. Your provider will prescribe the proper dosage for you. It’s important to take the medications exactly as prescribed and for as long as your provider says. This is necessary to clear up the infection and keep it from coming back.

Debridement

“Debridement” is the medical term for dead tissue removal. Gangrenous tissue is dead, and it won’t heal. The only option is to remove it. Doing so protects nearby healthy areas and helps damaged (but not dead) tissues heal. Your provider may perform traditional surgery to remove dead or infected tissue.

Another method is larval debridement therapy, a type of biosurgery. Larval debridement therapy uses maggots bred in a lab to remove damaged tissue. Your provider places these maggots on your wound and covers the area with a bandage. The maggots feed on the dead tissue. They don’t disturb healthy tissue. They also release substances that help your skin heal. This process takes a few days.

Procedures to improve blood flow

If peripheral artery disease causes dry gangrene, your provider may perform a procedure to widen arteries in that area of your body. This is called an angioplasty. Your provider may also insert a stent to keep the artery propped open.

Another option is to create a new path for blood to flow around arteries that are narrowed or blocked. That’s called bypass surgery.

Hyperbaric oxygen therapy (HBOT)

HBOT sends high levels of oxygen through your body’s tissues, helping to heal them. This treatment may help people who have gas gangrene or gangrene that’s due to diabetes-related foot ulcers.

Amputation

Amputation is the surgical removal of the affected body part, like a toe, foot, hand or finger. Healthcare providers use this option only if other treatments won’t do enough to save healthy tissues or save your life.

Skin graft surgery

After treatment to restore blood flow and remove dead or infected tissue, you may choose to have skin graft surgery. A provider uses healthy skin from another part of your body to cover scars or damaged skin.

When should I seek medical care?

Gangrene is serious and can be life-threatening. You need medical care right away. Call emergency services or go to your local ER if you have any gangrene symptoms, including:

• Blisters that release a foul-smelling pus
• Severe pain or loss of feeling in a limb
• Skin that crackles when you touch it
• Skin that looks greenish, purple or black

You should also seek emergency help if you have symptoms of septic shock:

• Fast but weak pulse
• Feeling confused or disoriented
• Feeling dizzy when you stand up
• Skin that’s cold, clammy and pale
• Trouble breathing
• Vomiting or diarrhea

What can I expect if I have this condition?

What you can expect, including your life expectancy, depends on many factors, including:

• How much the gangrene has spread
• How soon you receive treatment
• Which parts of your body are affected
• Your overall health

Your healthcare provider knows your situation best and can give you the most accurate prognosis.

Without treatment, gangrene can quickly become fatal. How long it takes for gangrene to cause death depends on the type of gangrene you have. Gas gangrene progresses very fast. The area of dead tissue can expand several inches with every hour that passes. Gas gangrene is always fatal without treatment, and sometimes fatal even with treatment.

For any type of gangrene, the sooner you get treatment, the better your chances of survival.