When the case is moderately advanced, very mild doses, gr. ½, morning and evening, of the thyroid extract may be given. It is generally believed that the internal secretion of the thyroid and the adrenal are antagonistic. That the thyroid secretion lowers blood pressure in certain forms of hypertension is certain, possibly on account of its iodine content. Some combinations of iodine and thyroid such as the iodothyroidin have been used and have had some measure of success attributed to them.
Hypertension does not always demand active measures for its reduction. Viewed from the physiologic standpoint, hypertension is but the expression of a compensating mechanism which is designed to keep the blood moving through narrowed channels. Heart hypertrophy then is absolutely essential to the maintenance of life. It has been said that the highest blood pressures occur in chronic disease of the kidneys. The poisonous substances produced in the kidneys must exert their action through absorption into the general blood stream. This toxin may be completely eliminated, if we accept as our criterion the reduction of tension to normal together with the complete return of the affected individual to health. A concrete example is as follows: A man aged 44 years was brought to the Milwaukee County Hospital in coma. His systolic blood pressure was over 280 mm. Hg, diastolic 170 mm., his urine contained considerable albumin and many casts. He had general anasarca. Venesection was done at once and 300 c.c. blood obtained. Immediately following this operation the pressure was 210-150, but within twelve hours it was again above 280-170. He was given no medication to reduce pressure except that he was freely purged. He was given a steam sweat bath daily. Frequent blood pressure readings were taken. Within seven days the pressure was 130-86. He had, in the meantime, completely recovered from his symptoms. He was kept in the hospital for two weeks longer assisting in the work on the ward, and he was discharged with a pressure (systolic) between 130 and 136 diastolic 80-84. The treatment was rest in bed, free purging, venesection, and sweat baths, simple but exceedingly effective.
Should there be actual indications for reducing the blood pressure, I must admit that it can not always be done. The majority of cases will do well on the sodium nitrite or erythrol tetranitrate. However, these do not always lower blood pressure and keep it within normal limits. When a man has very high tension we do not wish to reduce it to what it should normally be for the age of the patient, as symptoms of collapse might set in at any time under such conditions.
Observations made with the sphygmomanometer[20] show that the effect of nitroglycerin is transient or of no effect except in doses which are relatively enormous (one drop of the one per cent solution given every hour). Sodium nitrite may lower the blood pressure but the effects will have worn off in two hours. It is the same with erythrol tetranitrate. Sodium sulphocyanate in doses of from one to three grains three times a day is highly recommended by some. My own experience with it does not lead me to believe that it is of any great value in hypertension. It, however, may be tried. Benzyl benzoate has been used recently to reduce the high blood pressure of hypertension. Macht has reported some success. In the author's hands it has been efficacious in a few cases. As long as the patient takes the drug the pressure may be slightly reduced, but upon the withdrawal of the drug the pressure returns to its former level. It is well worth a trial and further experimentation may reveal better methods of administration. The dose is from 2 to 6 c.c. mixed with water at intervals.
In the hypertension of the menopause some have had success with large doses of corpus luteum extract. As a matter of fact the drug treatment of hypertension, when it becomes necessary to treat this condition with drugs, has suffered a notable set-back since more careful control has been made with the blood pressure instruments. In giving any of the depressor drugs their action should be controlled by blood pressure measurements, for only in this way can we be sure that the drug is exerting its physiological effect and we may expect results. The individual reaction to these drugs varies greatly and no rule for dosage can be dogmatically laid down. The only successful therapy is rigid individualization. This is the keystone to treatment in cases of arteriosclerosis and high tension.
It must not be inferred from what has been said that the nitrites are of no value. They are of decided value but they have their limitations. The most evanescent of these drugs is amyl nitrite. This is put up in the form of capsules, or pearls, containing from one to three minims. When it is desired to dilate the peripheral vessels suddenly, one or two of these capsules are broken in a cloth held to the nose. The effect is almost instantaneous. There is flushing of the face and other peripheral vessels, particularly near the head, denoting a relaxation and widening of the bed of the blood stream, and a consequent decrease in pressure in the arteries. These effects are over in a short while. It is only used in attacks of cardiac spasm, as in angina pectoris. Nitroglycerin, the Spiritus Glonoini of the U. S. P., acts in about the same manner as amyl nitrite but the effects last usually a trifle longer. One drop of the one per cent solution may be given every hour until physiologic effects are produced. It may be given hypodermically. This may be a means of reducing pronounced high tension. This drug has been found of benefit especially in cases where arteriosclerosis combined with chronic nephritis causes cardiac asthma. The other drug which may be of service in these conditions, one whose sphere of action is somewhat broader, because its effects are more lasting, is sodium nitrite. This is given in water in doses of one to three or five grains every four hours. Some have objected to the use of this drug, but my experience has made me place considerable confidence in its harmlessness, provided that the patient is carefully watched. This, however, applies to all of the nitrite compounds. My experience with erythrol tetranitrate is not large. It may be used in place of sodium nitrite.
For a mild case, one often finds that sweet spirits of niter is sufficient to control the pressure and relieve the distressing symptoms, and it is undoubtedly the least harmful of all the nitrites. Drugs that are of great value, but of which little is noted in textbooks, are aconite and veratrum viride. Both of these drugs are well known to be marked circulatory depressors. Veratrum viride in my experience should be very cautiously used, and never used unless a trained attendant is constantly at hand. With regard to aconite I have no such feeling, and a mixture of tincture of aconite and spiritus etheris nitrosi may be given for several weeks with no fear of doing any harm. Personally, of all the drugs mentioned, I prefer the nitrite of sodium or the combination just given. They may be advantageously alternated.
My own feeling is that the most successful means of treatment of acute high tension is without the use of drugs. The most important measure is absolute rest in bed. This often suffices to lower the blood pressure and to arrest the symptoms produced by high tension. Venesection I believe is also of value. True the arterioles appear to contract almost immediately upon the lessened quantity of blood, or there is immediate interchange of serum from the tissues which brings the blood volume back to the original amount. Whatever happens the pressure is not greatly reduced, at times not reduced at all, but often the symptoms are relieved. Hot packs or sweat baths assuredly do reduce the pressure in many cases. This seems to me to be an exceedingly valuable measure. Finally the diet should be nourishing, but very light, not too much fluid should be ingested, and the bowels should be freely opened.
With the fibrolysin of Merck, I have had no experience. Some men assert that they have had good results from its use, but on the whole the evidence is not highly favorable.
Morphine is invaluable. No drug is of such value in the nocturnal dyspneic attacks that occur in the late stages of arteriosclerosis when the heart or the kidneys are failing. Morphine not only relaxes spasm and quiets the cerebral centers, but is an actual heart stimulant under such conditions, and should never be withheld, as the danger of the patient's becoming addicted to its use is more fanciful than real. However, morphine, at times, suppresses the secretion of urine. So that if after trial the urine becomes scanty and the edema increases, recourse must be had to other drugs. The various hypnotics may be used with caution. One which seems to be very useful is adalin.