_Treatment._--The head should at once be lowered--in imitation of nature's method--to encourage the flow of blood to the brain, the patient, if necessary, being held up by the heels. All tight clothing, especially round the neck or chest, must be loosened. The heart may be stimulated reflexly by dashing cold water over the face or chest, or by rubbing the face vigorously with a rough towel. The application of volatile substances, such as ammonia or smelling-salts, to the nose; the administration by the mouth of sal-volatile, whisky or brandy, and the intra-muscular injection of ether, are the most speedily efficacious remedies. In severe cases the application of hot cloths over the heart, or of the faradic current over the line of the phrenic nerve, just above the clavicle, may be called for. #Surgical Shock.#--The condition known as surgical shock may be looked upon as a state of profound exhaustion of the mechanism that exists in the body for the transformation of energy. This mechanism consists of (1) the _brain_, which, through certain special centres, regulates all vital activity; (2) the _adrenal glands_, the secretion of which--adrenalin--acting as a stimulant of the sympathetic system, so controls the tone of the blood vessels as to maintain efficient oxidation of the tissues; and (3) _the liver_, which stores and delivers glycogen as it is required by the muscles, and in addition, deals with the by-products of metabolism. Crile and his co-workers have shown that in surgical shock histological changes occur in the cells of the brain, the adrenals, and the liver, and that these are identical, whatever be the cause that leads to the exhaustion of the energy-transforming mechanism. These changes vary in degree, and range from slight alterations in the structure of the protoplasm to complete disorganisation of the cell elements. The influences which contribute to bring about this form of exhaustion that we call shock are varied, and include such emotional states as fear, anxiety, or worry, physical injury and toxic infection, and the effects of these factors are augmented by anything that tends to lower the vitality, such as loss of blood, exposure, insufficient food, loss of sleep or antecedent illness. Any one or any combination of these influences may cause shock, but the most potent, and the one which most concerns the surgeon, is physical injury, _e.g._, a severe accident or an operation (_traumatic shock_). This is usually associated with some emotional disturbance, such as fear or anxiety (_emotional shock_), or with hæmorrhage; and may be followed by septic infection (_toxic shock_).