Gangrene describes tissue decay and death within the human body that most commonly affects fingers and toes, according MayoClinic.com. Gangrene can occur from a lack of blood, which starves the tissue of needed oxygen, or as the result of bacterial infection, injury or disease. Many conditions, including diabetes, have the potential to increase the chance of gangrene.
Trauma or Infection
Trauma or infection afflicts an area of the body. Gangrene usually occurs after trauma or surgery. According to the website HealthExpertAdvice, onset of gangrene usually happens 24 hours to three days after the injury or operation.
Gas Gangrene
Gas gangrene is very rare, according to MedlinePlus. It often occurs suddenly near an incision from surgery or other trauma. Signs and symptoms include air under the skin, blisters, fever, high heart rate and pale and sweaty skin. This very dangerous condition needs to be treated immediately or it may become life threatening.
Restriction of Blood Supply
The initial injury or disease restricts blood flow to the affected area of the body. Blood vessels may be destroyed or so badly deteriorated that they cannot effectively deliver blood to the area, nor can the blood carry toxins away from the site.
Oxygen Depletion
Blood carries oxygen to the body. When blood flow is restricted, tissue cannot receive the oxygen needed to survive. The area around the affected site may be quite painful as the tissue becomes distressed from lack of blood and oxygen. The area may become swollen.
Tissue Distress
If an internal organ is gangrenous, the victim may grow confused. This may be from the body's metabolic system trying to increase the amount of oxygen delivered to the distressed organ or tissue. Fever is a sign of a gangrenous internal organ as the body tries to combat the tissue decay. The patient may also experience low blood pressure and a feeling of general illness.
Release of Gases
Some types of gangrenous infections cause carbon dioxide and hydrogen gases to be released as tissue dies. The gas creates bubbles at the skin site, and the skin feels crackly when pressed, according to The Merck Manual of Medical Information.
