If bleeding does not stop quickly with pressure from the thumb, a substitute can be arranged in the form of a clean pad, such as a roll of lint or a tightly folded handkerchief firmly fixed by means of a bandage, such as the triangular bandage described in the first article of this series. (page 62).
If the bleeding is recognised as arterial, it should be controlled by pressure on some part of the injured artery between the wound and the heart-that is to say. at one of the special places known as pressure points. This will be de- scribed later.
Styptics are often of service. They are sub- stances which check the flow of blood by causing it to cover the injury with a clot. Most styptics must be regarded as within the province of the doctor, but there are certain homely ones available. Such are fresh air. cold water, ice, cold tea, tobacco leaf, ravellings of clean linen or flannel, etc. A clot once formed must never be washed away. It is Nature's dressing, which guards the wound against the intrusion of harmful germs. Position is of great im- portance in cases of haem- orrhage. Exertion makes the heart beat rapidly. When one is sitting still the heart movement is slower than when standing erect, and when the body is reclining it is slower still. The flow of blood from a wound varies in severity according to the pulsation of the heart. Patients, therefore, should be placed so as to retard the circulation. When the injured blood-vessel belongs to an arm or leg, keep the limb in an elevated position until the bleeding has ceased. Arterial Haemorrhage The course of the main arteries through the body must be understood, so that pressure may be exerted at the proper pressure points. The blood-vessel through which blood first passes from the heart is known as the aorta. The first part is arched like a shepherd's crook, and from the top of this three smaller vessels spring. These are known as the left subclavian, left common carotid, and innominate respec- tively. The innominate soon divides again into th'i right subclavian and right common carotid, which correspond with those of similar name on the other side. Tracing the course of these vessels, we find that the right and left subclavians pass up to the root of the neck, lying between the collar- bone and the first rib. When the head is turned aside and the thumb inserted in the hollow or " salt cellar," thus made, the pulse can be felt, and when the artery is pressed against the bone behind it. the circulation between this point and the finger-tips is arrested (see illustration). The subclavian artery passes next into the arm-pit. and. here again, the pulse can be felt when the clothing is removed. Leaving the arm-pit, the artery takes a half-turn over the bone of the arm to reach the inner or flexure side of the elbow joint. By grasping the arm firmly from back to front, so that the fingers press along the inner edge of the biceps muscle, the pulse can be again arrested (see illustration). The next point is on the inner side of the elbow joint. There the artery divides into two vessels of equal size, which pass down the forearm, lying close to the bones of the forearm and well^ protected by the surrounding muscle. At either side of the wrist the arteries are near the surface, and this is the point which is most conveniently utilised for testing the action of the heart by " feeling the pulse." The artery on the little finger side passes to the front of the wrist and runs along the " line of life " at the ball of the thumb. The other passes to the back of the wrist and is placed deeply between the thumb and forefinger to reach the palm of the hand. In the palm both arteries form arches from which branches con- tinue forward along the sides of the fingers where they are best protected. The common carotids lie on either side of the wind- pipe until they reach the skull, and their pulsation may be felt by light digital Control of bleeding below elbow by pressure on brachial artery Control of the subclavian artery pressure against the windpipe. Each vessel crosses the lower jaw, a little in front of the angle of the jaw, whence it sends branches to the chin, lips, nose, and cheek. The temporal artery may be felt in front of the upper part of the ear, while the occipital artery is as plainly felt four fingers' breadth behind the ear Following the aorta downwards, it is known as the thoracic and abdominal aorta as it passes through those parts of the trunk respectively. About halfway down the abdomen it divides into two. One branch is known as the internal iliac, and supplies the organs situated in the pelvis. The other, the external iliac, divides and enters the lower limbs exactly at the centre
