Ligature, or tying the artery, is a very old method of arresting hemorrhage, and cer tainly the best. It was not used generally, however, in operations until improved ana tomical knowledge and more efficient tourniquets allowed surgeons the time necessary for its application. See LioierunE.
Another method was introduced by the late sir James Y. Simpson of Edinburgh, and has been already extensively used. lie termed it acfi-pressure, or pressure from a long needle or pin inserted from without, so as to press the artery between it and the tissues. The pins are removed after 24 or 48 hours, the period being proportioned to the size of artery to be secured. This new plan promises to supersede the ligature, in amputations especially, where the vessels can be easily secured, and where occasionally they are found so brittle from disease (see AznEnomA) as to break under the pressure of a thread.
Venous B. is recognized by the dark color of the blood, and its continuous flow. Pressure is generally found sufficient to arrest it, and it should be applied directly over the wounded part. Ligatures are not used to secure cut ends of veins, as inflammation of the lining membrane of these vessels is apt to spread along them towards the heart (see Pm.Euens), and produce dangerous symptoms, and very frequently fatal results. There is not the same objection to the of acil-pressure pins. Of course, if a large vein is wounded in a part where compression cannot be readily applied, the surgeon should have no hesitation as to tying it; and if it is not cut quite through, he may pick up the cut edges in a forceps, and tie them so as to still permit a flow of blood throu0h the vein.
Oozing from cut surfaces of course partakes of the characters of venous and arterial B., but there is no vessel sufficiently large to demand a ligature pressure. The actual cautery and cold may then be used, or one of the many styptics, the strong perchloride of iron may be specially recommended; it may be applied on lint ova sponge; or astrin gents, such as alum and tannin; there are also the puff-ball, mushroom, agaric, and matico leaves, cobwebs, felt, etc., which act mechanically, and owe their reputation chiefly to the pressure used in their application. Some persons have a congenital ten dency to bleed (the hemorrhagic diathesis); if such a one have a trifling cut, or have a tooth pulled, he bleeds perhaps to death. A prudent surgeon trill not perform cutting operations on one of a hemorrhagic family.
B. from the free surfaces of mucous membranes occurs when they are much con gested. One may have fatal hemorrhage from the stomach, and yet no open vessels may be found after death, even on the most careful examination. In such a ease, we must trust to cold and internal remedies, such as acetate of lead combined with opium.