The cause of the pulsation lies in the fact that, at each heartbeat, 80–90 millilitres of blood are driven into the AORTA, and a ?uid wave, distending the vessels as it passes, is transmitted along the ARTERIES all over the body. This pulsation falls away as the arteries grow smaller, and is ?nally lost in the minute capillaries, where a steady pressure is maintained. For this reason, the blood in the veins ?ows steadily on without any pulsation. Immediately after the wave has passed, the artery, by virtue of its great elasticity, regains its former size. The nature of this wave helps the doctor to assess the state of the artery and the action of the heart.
The pulse rate is usually about 70 per minute, but it may vary in health from 50 to 100, and is quicker in childhood and slower in old age than in middle life; it is low (at rest) in physically ?t athletes or other sports people. Fever causes the rate to rise, sometimes to 120 beats a minute or more.
In childhood and youth the vessel wall is so thin that, when su?cient pressure is made to expel the blood from it, the artery can no longer be felt. In old age, however, and in some degenerative diseases, the vessel wall becomes so thick that it may be felt like a piece of whipcord rolling beneath the ?nger.
Di?erent types of heart disease have special features of the pulse associated with them. In atrial FIBRILLATION the great character is irregularity. In patients with an incompetent AORTIC VALVE the pulse is characterised by a sharp rise and sudden collapse. (See HEART, DISEASES OF.)
An instrument known as the SPHYGMOGRAPH registers the arterial waves and a polygraph (an instrument that obtains simultaneous tracings from several di?erent sources such as radial and jugular pulse, apex beat of the heart and ELECTROCARDIOGRAM (ECG)) enables tracings to be taken from the pulse at the wrist and from the veins in the neck and simultaneous events in the two compared.
The pressure of the blood in various arteries is estimated by a SPHYGMOMANOMETER. (See BLOOD PRESSURE.)... pulse
Arrangement of the bones In childhood, the bones are independent, gradually fusing together by sutures, and in old age fusing completely so that the cranium forms a solid bony case. At the time of birth the growth of several bones of the infant’s head has not been quite completed, so that six soft spots, or fontanellas, present; here the brain is covered only by skin and membranes, and the pulsations of its blood vessels may be seen. One of these spots, the anterior fontanelle, does not close completely until the child is 18 months to 2••• years old.
Parts of the skull The cranium, enclosing the brain, consists of eight bones, while the face, which forms a bony framework for the eyes, nose and mouth, consists of 14 bones. These two parts can be detached.
Shape of the skull The development of large central hemispheres of the brain in humans has in?uenced the skull shape. Unlike in other mammals, the cranium extends above as well as behind the face which therefore looks forwards. The skull’s proportions change with age: the cranium in children is larger in comparison with the face – one-eighth of the whole head – than is the case in adults, where sizes are about the same. Old age reduces the size of the face because of the loss of teeth and absorption of their bony sockets. Women’s skulls tend to be lighter and smoother with less obvious protuberances than those in men.... skull
Action: vein-restorative, hypotensive, anti-haemorrhage, vasodilator. Contains Rutin, an anti-coagulant. Source of magnesium.
Uses: Radiation damage, high blood pressure, capillary fragility, varicose veins, petechiae, retinal haemorrhage, spontaneous bruising, circulatory stasis, purple patches on skin due to capillary haemorrhages, temporal arteritis, visible pulsation of carotid artery in the neck, frostbite, chilblains. Preparations. Green Buckwheat tea (Rutin); a caffeine-free tea. One heaped teaspoon to each cup boiling water. Half-1 cup as desired.
Formula. Tablets or capsules: Rutin 60mg; Vitamin C 20mg; Chlorophyll 20mg. ... buckwheat