WOUNDS AND THEIR TREATMENT. 485 
HEMOSTASIA., 
By this term is meant the checking of the flow of blood. It may be 
accomplished by several methods, such as compress bandages, torsion, 
hot iron, and ligatures. The heat from a hot iron will cause the im- 
mediate clotting of the blood in the vessels, and this clot is further 
supported by the production of a scab, or crust, over the portion 
seared. The iron should be at a red heat. If at a white heat, the 
tissue is charred, which makes it brittle and the bleeding is liable to 
be renewed. If the iron is at a black heat, the tissue will stick to the 
iron and will pull away from the surface of the wound. Cold water 
and ice bags quickly stop capillary bleeding, while hot water is pref- 
erable in more excessive hemorrhages. Some drugs, called styptics, 
possess the power of contracting the walls of blood vessels and also 
of clotting the blood. A solution of the chlorid of iron placed on a 
wound alone or by means of cotton drenched in the liquid produces a 
rapid and hard clot. Tannic acid, alum, acetic acid, alcohol, and oil 
of turpentine are all more or less active in this respect. To check 
bleeding from large vessels compression may be adopted. When it is 
rapid and dangerous and from an artery, the fingers may be used for 
pressing between the wound and the heart (digital compression), but 
if from a vein, the pressure should be exerted on the other side of the 
wound. Tourniquet may also be used by passing a strap around the 
part and tightening after placing a pad over the hemorrhage. The 
rubber ligature has now replaced the tourniquet and is bound tightly 
around the limb to arrest the bleeding. Tampons, such as cotton, tow, 
or oakum, may be packed tightly in the wound and then sewed up. 
After remaining there for twenty-four or forty-eight hours they are 
removed. Bleeding may sometimes be easily checked by passing a 
pin under the vessel and by taking a horsehair and forming a figure 
8 by running it above and below the pin, thus causing pressure on the 
vessel. Torsion is the twisting of the blood vessel until the walls 
come together and form a barrier to the flow of blood. It may be ac- 
complished by the fingers, forceps, or by running a pin through the 
vessel, turning it several times, and then running the point into the 
tissue to keep it in a fixed position. 
Ligation is the third method for stopping a hemorrhage. The 
blood vessel should be seized with the artery forceps, a clean thread 
of silk passed around it, and tied about one-half inch from its end. 
The silk should be sterilized by placing it in an antiseptic solution so 
as not to impede the healing process or cause blood poisoning or 
lockjaw, which often follows the ligation of a vein with unsterilized 
material. Sometimes it will be impossible to reach the bleeding 
vessel, so it is necessary to pass the ligature around a mass of tissue 
which includes the blood vessel. Ligation is the most useful method 
