Thyroid Extract: In slow hearts and in sluggish circulation, often in old age, quite frequently in arteriosclerosis and in every condition of insufficient thyroid secretion (these instances are frequent), small doses of thyroid extract will benefit the circulation. Its satisfactory action is to increase the cardiac activity, slightly lower the blood pressure, and increase the peripheral circulation and the health of the skin. If it causes tachycardia, nervous excitement, sleeplessness or loss of weight, it is doing harm and the dose is too large, or it is not indicated. The dose for the cardiac action desired is a tablet representing from 1/2 to 1 grain of the active substalice of the thyroid gland, given once a day, continued for a long period.
When an improved peripheral circulation is desired, and especially when a reduction of the pressure in the heart is desired and a diminished amount of blood in overfilled arteries is indicated, the value of the sitzbath, hot foot-baths, warm liquids (not hot) in the stomach, and warm, moist applications to the abdomen should all be remembered.
4. Cardiac Nutritives.—Iron: Nothing is of more value to a weakened heart muscle, when the nutrition is low, the patient anemic, and the iron of the food not properly metabolized, than tonic doses of some iron salt. It has frequently been repeated, but should constantly be reiterated, that there is no physiologic reason or therapeutic excuse for the patient to pay a large amount of money for some organic iron preparation.
Small doses of an inorganic salt act perfectly, and nothing will act better. As previously suggested, a drop or two of the tincture of iron, a grain or two of the reduced iron, or 2 or 3 grains of saccharated ferric oxid, given once or twice in twenty-four hours, is all the iron the body needs from the points of view of the blood and the heart.
Calcium: It has lately been learned that calcium is an element which a heart needs for perfect activity. Many patients who are ill lose their calcium, and they may not receive a sufficient amount of it unless milk is given them. Even if such patients are taking milk, the heart and the whole general condition sometimes such; to improve when calcium is added to the diet. It may be given either in the form of lime water, calcium lactate or calcium glycerophosphate. If a medium-sized dose is given three or four times in twenty-four hours, it is sufficient and will often act for good.
Whether calcium can do harm in a chronic endocarditis or an arteriosclerosis to offset the value that it seems to have in quieting the nervous system and in being of value to a weak or nervously irritable heart is a question which has not been decided. Theoretically lime should not be given when there is a tendency to calcification, or when a patient is past middle age. Lime seems to be essential to youth, and to the welfare of nervous patients.
EMERGENCIES
5. Cardiac Emergency Drugs.—Besides some of the drugs already mentioned (such as camphor hypodermically, nitroglycerin when indicated, strophanthin hypodermically or intravenously, caffein and strychnin), often ergot, suprarenal vasopressor principle, pituitary vasopressor principle, atropin and morphin should be considered.
When there is low blood pressure, venous stasis, pulmonary congestion, cyanosis and a laboring, failing heart, intramuscular injections of ergot, with or without coincident venesection, may be the most valuable method of combating the condition. Life has been saved in this kind of sudden acute cardiac failure in valvular disease. When venesection is not indicated in certain conditions of low blood pressure and heart failure, ergot has saved life. It causes contraction of the blood vessels and seems to tone the heart. Incidentally it quiets the central nervous system. If the blood pressure is much increased by it, the ergot should not be repeated, as too much work should not be thrown on the heart muscle. Often, however, it may be administered intramuscularly with advantage in aseptic preparation as offered in ampules, at the rate of one ampule every three hours for two or three times, and then once in six hours for a few times, the future frequency depending on the indications.
Epinephrin and Pituitary Extract: The blood pressure-raising substance of the suprarenals or of the pituitary gland (hypophysis cerebri) has been much used in heart failure. These substances certainly would not be indicated in high blood pressure; they are indicated in low blood pressure. They have been given intravenously; they are frequently given hypodermically. They often act rapidly when a solution in proper dose is dropped on the tongue. The blood pressure rise from epinephrin is quickly over; that from the pituitary extract lasts longer. In large doses, or when it is too frequently repeated, epinephrin depresses the respiration. Pituitary extract acts as a diuretic. Sterilized solutions of both, put up in ampules ready for hypodermic medication, are obtainable, the strength offered generally being 1 part of the active principle to 10,000 of the solution. Hypodermic tablets of epinephrin may also be obtained. Stronger solutions of 1 part to 1,000 may be dropped on the tongue, or tablets may be dissolved on the tongue. The blood pressure is temporarily raised and the heart stimulated by these treatments, but epinephrin is not used so often for cardiac failure as it was a short time ago.