Gangrene signifies the mortification or death of a part of the body, owing to failure in nutrition, and death of soft tissue. There are two forms of gangrene - the dry or senile, and the moist. Dry gangrene - mummification - occurs from death of the soft tissue of parts exposed to the air, and results from defective blood-supply owing to feebleness of the circulation and changes in the vessels. The diseased part becomes engorged with blood, and the coloring matter transudes the tissues, and the part assumes a dark red or purple appearance. The tissues begin to dry from evaporation, and the affected part becomes leathery, hard, and brittle, and also black; between the dead and sound tissues there is an inflammatory zone, or line of demarkation. Usually there are no general constitutional symptoms. Moist gangrene is a form of the disease where the death of the soft tissue is followed by decomposition and putrefaction, the result of the presence of micro-organisms entering either through the air or the circulation. The decomposed tissue has the characteristic odor of putrid animal matter, disintegrating and liquefying. Gases form, causing puffiness of the part, pressure on which causes crepitation. The symptoms of moist gangrene are those of acute inflammation, great congestion and an intense burning pain. The constitutional symptoms are a low type of inflammatory fever, rapid feeble pulse, and low delirium.

A frequent cause of gangrene is inflammation of the walls of the arteries (arteritis), which results in the formation of new tissue within the walls of the vessels, and obstructs the flow of the blood.

Treatment

The treatment of gangrene consists in efforts to remove the primary cause, support the strength by a generous diet, and use of stimulants. Digitalis is indicated in case of a feeble heart, and bitter tonics to improve the appetite. When gangrene attacks the face and mouth, the dead tissue should be removed as soon as the line of demarkation is established, and the wound treated on antiseptic principles. Boric acid solution and Thiersch solution are valuable antiseptics for use in the oral cavity.