Gangrene is a term used to describe the decay or death of an organ, tissue, or bone caused by a lack of oxygen and nutrients. It is a complication resulting from tissue injuries (such as frostbite), the obstruction of blood flow, or the processes of chronic diseases such as diabetes mellitus. Externally, the hands and feet are the areas most often affected by gangrene; internally, it is most likely to affect the gallbladder and the intestines. Gangrene is referred to as wet, or moist, if a bacterial infection is involved. In dry gangrene, there is no infection.
Description
Gangrene is often characterized by pain followed by numbness. The infection may first go unnoticed, especially in the elderly or those individuals with a loss of sensation. The area affected by gangrene may be cold and pale, especially early in the disease. Blisters may be apparent and the patient may experience an increased heart rate and profuse sweating. As the tissue dies, the skin begins to darken. The dead tissue gradually separates and falls away from the healthy tissue.
Dry gangrene is often seen in advanced cases of diabetes and arteriosclerosis. The tissue doesn’t become infected, rather it dries out and shrivels over a period of weeks or months. Wet gangrene progresses much more rapidly. The affected area becomes swollen and gives off a foul smelling discharge. Death may occur within a matter of hours or days. Fever, rapid heart rate, rapid breathing, altered mental state, loss of appetite, diarrhea, vomiting, and vascular collapse may occur as the infection progresses.
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Causes & symptoms
The primary cause of gangrene is often an injury to the blood vessels, causing either an interruption of blood flow, the introduction of a bacterial infection, or both. Such injuries may include burns, infected bedsores, boils, frostbite, compound fractures, deep cuts, or gunshot wounds.
Gangrene can also develop due to the poor circulation and obstructions in the blood vessels associated with abnormal blood clots, torsion of organs, and diseases such as diabetes, heart disease, and Raynaud’s disease. Gangrene of the internal organs may be attributed to a ruptured appendix, internal wounds, or the complications of surgery.
The bloodstream is the body’s main transport system. When blood flow is diminished, the flow of the oxygen and nutrients needed to keep tissues healthy is greatly decreased. The white blood cells needed to fight infection are not readily available. In such an environment, invading bacteria thrive and multiply quickly. Streptococcus spp. and Staphylococcus spp. are the most common agents of external skin infection.
Gas gangrene, also called progressive or clostridial myonecrosis, is a type of moist gangrene most commonly caused by an infection of Clostridium perfringens, or other species that are capable of thriving under conditions where there is little oxygen. These bacteria produce gases and poisonous toxins as they grow in the tissues.
Gas gangrene causes the death of tissue, the destruction of red blood cells, and the damaging of the walls of the blood vessels and parts of the kidneys. Early symptoms include sweating, fear, and anxiety. Gas gangrene is a life-threatening condition and should receive prompt medical attention.
Diagnosis
A diagnosis of gangrene will be based on a combination of patient history, a physical examination, blood test results, and other laboratory findings. A physician will look for a history of recent trauma, surgery, cancer, or chronic disease. Blood tests will be used to determine whether infection is present and to determine how much the infection has spread.
A sample of drainage from a wound or obtained through surgery may be tested to identify the bacteria causing the infection and to aid in determining treatment. In the case of gas gangrene, the gas produced by the bacteria may be detected beneath the skin by pressing into the swollen areas. The crackling sounds of gas bubbles may also be heard in the affected area and the surrounding tissues.
X-ray studies and other imaging techniques, such as computed tomography (CT) scans or magnetic resonance imaging (MRI), may be helpful in making a diagnosis by showing evidence of gas accumulation or muscle tissue death. These techniques, however, are not sufficient alone to provide an accurate diagnosis of gangrene. Precise diagnosis often requires surgical exploration of the wound.
Treatment
Chelation therapy is a treatment that uses an intravenous solution containing the drug ethylenediamine tetra-acetic acid (EDTA), among other substances. In the bloodstream, EDTA binds and removes toxins and plaque formation on arterial walls. It promotes circula-
