Cautery.—­The actual cautery or Paquelin’s thermo-cautery is seldom employed to arrest haemorrhage, but is frequently useful in preventing it, as, for example, in the removal of piles, or in opening the bowel in colostomy.  It is used at a dull-red heat, which sears the divided ends of the vessel and so occludes the lumen.  A bright-red or a white heat cuts the vessel across without occluding it.  The separation of the slough produced by the charring of the tissues is sometimes attended with secondary bleeding.

Haemostatics or Styptics.—­The local application of haemostatics is seldom to be recommended.  In the treatment of epistaxis or bleeding from the nose, of haemorrhage from the socket of a tooth, and sometimes from ulcerating or granulating surfaces, however, they may be useful.  All clots must be removed and the drug applied directly to the bleeding surface.  Adrenalin and turpentine are the most useful drugs for this purpose.

Haemorrhage from bone, for example the skull, may be arrested by means of Horsley’s aseptic plastic wax.  To stop persistent oozing from soft tissues, Horsley successfully applied a portion of living vascular tissue, such as a fragment of muscle, which readily adheres to the oozing surface and yields elements that cause coagulation of the blood by thrombo-kinetic processes.  When examined after two or three days the muscle has been found to be closely adherent and undergoing organisation.

#Arrest of Accidental Haemorrhage.#—­The most efficient means of temporarily controlling haemorrhage is by pressure applied with the finger, or with a pad of gauze, directly over the bleeding point.  While this is maintained an assistant makes digital pressure, or applies a tourniquet, over the main vessel of the limb on the proximal side of the bleeding point.  A useful emergency tourniquet may be improvised by folding a large handkerchief en cravatte, with a cork or piece of wood in the fold to act as a pad.  The handkerchief is applied round the limb, with the pad over the main artery, and the ends knotted on the lateral aspect of the limb.  With a strong piece of wood the handkerchief is wound up like a Spanish windlass, until sufficient pressure is exerted to arrest the bleeding.

When haemorrhage is taking place from a number of small vessels, its arrest may be effected by elevation of the bleeding part, particularly if it is a limb.  By this means the force of the circulation is diminished and the formation of coagula favoured.  Similarly, in wounds of the hand or forearm, or of the foot or leg, bleeding may be arrested by placing a pad in the flexure and acutely flexing the limb at the elbow or knee respectively.