One of the principal retrograde changes that takes place in a living body is gangrene. Gangrene means the "death of a part." It means that a certain area of the body's soft tissue has been deprived of one or all of the sources of elements that rebuild depleted cells. The result is the death and then decay of this area of tissue.
Gangrene is usually divided into two principal categories: dry and moist. Diabetic gangrene, which is very common today, and gas gangrene are in the moist category.
Basic mummification, which refers to local diminution in the blood supply due to an obstruction in the arterial system, is in the dry category. Dry gangrene usually occurs in the extremities. The tissues become dried out and eventually turn black.
With dry gangrene, the important point for every embalmer to remember is there is little, if any, chance that preservative chemicals used in the embalming process will reach areas that died because they have been deprived of the elements necessary for life.
Start by injecting the remainder of the body as you would do in an "average case." It then will be necessary to either treat the gangrenous tissue by hypodermic injection or by applying cotton or gauze packs saturated with a penetrating preservative chemical and then wrapping the affected area in a plastic wrap such as Saran wrap.
Moist gangrene is a condition which can be found in almost any part of the body and is due to an invasion by saprophytic organisms. The invasion, which causes putrefactive changes, can be through a wound or from the respiratory or intestinal tract.
The embalmer needs to exercise great caution in personal cleanliness and safety in handling these cases. Furthermore, a liberal amount of disinfectant spray should be applied to the exterior of the body and a strong deodorant should be sprayed around the preparation room, as these cases generally produce a great and unpleasant odor.
A strong solution of embalming fluid (at least a 3 percent strength) should be used. The common carotid artery should be the initial place of injection, and drainage should be taken from the internal jugular vein. However, these types of cases usually show little drainage. It is also advisable to use multiple injection sites to ensure tissue saturation.
Cavity treatment should be the regular aspiration of the cavities and the injection of two 16-ounce bottles of a quality cavity chemical.