Читать книгу Alcohol: A Dangerous and Unnecessary Medicine, How and Why - Martha Meir Allen - Страница 41

The organs of circulation are the heart and the blood-vessels. The blood-vessels are of three kinds, arteries, capillaries and veins. The arteries carry blood from the heart to the capillaries; the veins collect it from the capillaries and return it to the heart. There are two distinct sets of blood-vessels in the body, both connected with the heart; one set carries blood to, through and from the lungs, the other guides its flow through all the remaining organs; the former are known as the pulmonary, the latter as the systemic blood-vessels.

The smallest arteries pass into the capillaries, which have very thin walls, and form very close networks in nearly all parts of the body; their immense number compensating for their small size. It is while flowing in these delicate tubes that the blood does its nutritive work, the arteries being merely supply-tubes for the capillaries, through whose delicate walls liquid containing nourishment exudes from the blood to bathe the various tissues.

The quantity of blood in any part of the body at any given time is dependent upon certain relations which exist between the blood-vessels and the nervous system. The walls of the arteries are abundantly supplied with involuntary muscular fibres, which have the power of contraction and relaxation. This power of contraction and relaxation is controlled by certain nerves called vasomotor nerves, because they cause or control motion in the vessels to which they are attached. When arteries supplying blood to any particular part of the body contract, the supply of blood to that part will be diminished in proportion to the amount of contraction. If the nervous control be altogether withdrawn, the arterial walls will completely relax, and the amount of blood in the part affected will be increased correspondingly.

Alcohol, even in moderate doses, paralyzes the vasomotor nerves which control the minute blood-vessels, thus allowing these vessels to become dilated with the flowing blood.

“With the disturbance of power in the extreme vessels, more disturbance is set up in other organs, and the first organ that shares in it is the heart. With each beat of the heart a certain degree of resistance is offered by the vessels when their nervous supply is perfect, and the stroke of the heart is moderate in respect both to tension and to time. But when the vessels are rendered relaxed, the resistance is removed, the heart begins to run quicker like a clock from which the pendulum has been removed, and the heart-stroke is greatly increased in frequency. It is easy to account in this manner for the quickened heart and pulse which accompany the first stage of deranged action from alcohol.”—Richardson.

Dr. Parkes of England, assisted by Count Wollowicz, conducted inquiries upon the effects of alcohol upon the heart, with a young and healthy man. At first they made accurate count of the heart beats during periods when the young man drank water only; then of the beats during successive periods in which alcohol was taken in increasing quantities. Thus step by step they measured the precise action of alcohol on the heart, and thereby the precise primary influence induced by alcohol. Their results are stated by themselves as follows:—

“The average number of beats of the heart in 24 hours (as calculated from eight observations made in 14 hours), during the first, or water period, was 106,000; in the earlier alcoholic period it was 127,000, or about 21,000 more; and in the later period it was 131,000, or 25,000 more.

“The highest of the daily means of the pulse observed during the first, or water period, was 77.5; but on this day two observations are deficient. The next highest daily mean was 77 beats.

“If, instead of the mean of the eight days, or 73.57, we compare the mean of this one day; viz. 77 beats per minute, with the alcoholic days, so as to be sure not to over-estimate the action of the alcohol, we find:—

“On the 9th day, with one fluid ounce of alcohol, the heart beat 4,300 times more.

On the 10th day, with two fluid ounces, 8,172 times more.

On the 11th day, with four fluid ounces, 12,960 times more.

On the 12th day, with six fluid ounces, 20,672 times more.

On the 13th day, with eight fluid ounces, 23,904 times more.

On the 14th day, with eight fluid ounces, 25,488 times more.

But as there was ephemeral fever on the 12th day, it is right to make a deduction, and to estimate the number of beats in that day as midway between the 11th and 13th days, or 18,432. Adopting this, the mean daily excess of beats during the alcoholic days was 14,492, or an increase of rather more than 13 per cent.

The first day of alcohol gave an excess of 4 per cent., and the last of 23 per cent.; and the mean of these two gives almost the same percentage of excess as the mean of the six days.

Admitting that each beat of the heart was as strong during the alcoholic period as in the water period (and it was really more powerful), the heart on the last two days of alcohol was doing one-fifth more work.

“Adopting the lowest estimate which has been given of the daily work of the heart; viz. as equal to 12.2 tons lifted one foot, the heart during the alcoholic period, did daily work excess equal to lifting 15.8 tons one foot, and in the last two days did extra work to the amount of 24 tons lifted as far.

“The period of rest for the heart was shortened, though, perhaps, not to such an extent as would be inferred from the number of beats, for each contraction was sooner over. The heart, on the fifth and sixth days after alcohol was left off, and, apparently at the time when the last traces of alcohol were eliminated, showed in the sphygmographic tracing signs of unusual feebleness; and, perhaps, in consequence of this, when the brandy quickened the heart again, the tracings showed a more rapid contraction of the ventricles, but less power than in the alcoholic period. The brandy acted, in fact, on a heart whose nutrition had not been perfectly restored.”

Richardson quotes these experiments of Parkes and Wollowicz as if he agrees with them that increased heart-beat must of necessity mean increased work done by the heart. Dr. Nathan S. Davis, Dr. Newell Martin, Dr. A. B. Palmer, and some other investigators, show conclusively that mere increased frequency of beat above the natural standard is no evidence of increased force or efficiency in the circulation.

“The more frequent beats under the influence of alcohol constitute no exception to the general rule, for while the heart beats more frequently, its influence on the vasomotor nerves causes dilatation of the peripheral and systemic blood-vessels, as proved by the pulse-line written by the sphygmograph, which more than counterbalances the supposed increased action of the heart. The truth is, that under the influence of alcohol in the blood the systolic action of the heart loses in sustained force in direct proportion to its increase in frequency, until, by simply increasing the proportion of alcohol, the heart stops in diastole, as perfectly paralyzed as are the coats of the smaller vessels throughout the system. This was clearly demonstrated by the experiments of Professor Martin of Johns Hopkins University, to determine the effects of different proportions of alcohol on the action of the heart of the dog; and those of Drs. Sidney Ringer and H. Sainsbury, to determine the relative strength of different alcohols as indicated by their influence on the heart of the frog. Professor Martin states that blood containing ¼ per cent. by volume of absolute alcohol, almost invariably diminishes, within a minute, the work done by the heart.”

(This estimate would equal in an adult man an amount equal to the absolute alcohol in two or three ounces of whisky or brandy.)

“These investigations of Professor Martin, being directly corroborated by those of Drs. Ringer and Sainsbury, complete the series of demonstrations needed to show the actual effects of alcohol on the cardiac, as well as on the vasomotor, and also on the direct contractability of the muscular structure, when supplied with blood containing all gradations in the relative proportion of alcohol, leaving no longer any basis for the idea, popular both in and out of the profession, that alcohol in any of its forms is capable of increasing, even temporarily the force or efficiency of the heart’s action.”—Dr. N. S. Davis in Influence of Alcohol On the Human System.

The following letter will be of great interest to all students of the physiological effects of alcohol:—

“Chicago, Ill., March 3, 1899.

“To Mrs. Martha M. Allen,

“Syracuse, N. Y.,

“Madam: Your letter asking my attention to the apparent contradiction of authorities concerning the work done by the heart when influenced by alcohol was received yesterday.

“The explanation is not difficult. It depends entirely on the different views of what constitutes the work of the heart.

“One class of investigators, led by the original and valuable experiments of Parkes and Wollowicz base their estimate of the heart’s work entirely on the number of times it contracts or beats per minute. Thus Dr. Parkes, finding that moderate doses of alcohol increased the number of contractions of the heart from three to six beats per minute more than natural, readily estimated the number of additional contractions that would occur in twenty-four hours, and thereby demonstrated a large amount of increased work done by the heart under the influence of alcohol. All writers who speak of ‘stimulating’ or increasing the action of the heart by alcohol follow this method of measuring the amount of work done. They generally add that it is like applying ‘the whip to a tired horse.’

“The other class of investigators who claim that alcohol diminishes the actual work done by the heart base their estimates on the amount of blood the heart passes through its cavities into the arteries in a given time. This is the physiological function of the heart; i.e. to aid in circulating the blood. Professor Martin’s experiments were admirably contrived to determine, not how frequently the heart beat, but the amount of blood it delivered per minute under the influence of alcohol and without alcohol.

“He, and all others who take this basis of work, found that alcohol in any dose diminished the efficiency of the heart in circulating the blood in direct ratio to the quantity taken.

“My own original experiments, made fifty years ago, uniformly showed that alcohol quickly increased the number of heart beats per minute, but at the same time diminished the efficiency of the circulation generally. Every experienced practitioner knows that the weaker the heart becomes, the faster it beats. Consequently, the number of times the heart contracts per minute is no measure of the efficiency of its work in circulating the blood. Indeed the mechanism of the heart is such that there must be sufficient time between each of its contractions for its cavities to fill, or it is made to contract on an insufficient supply, and the efficiency of the circulation is diminished.

“Yours respectfully,

“N. S. Davis.”

The International Medical Congress of 1876 adopted as its reply to the Memorial of the National Temperance Society, and of the National Woman’s Christian Temperance Union respecting “Alcohol as a Food and as a Medicine,” the paper by Dr. Ezra M. Hunt, one conclusion of which was, “Its use as a medicine is chiefly that of a cardiac stimulant.”

As experiments conducted since that time show that it is not a cardiac stimulant, but a direct cardiac paralyzant, what excuse is there for using it as a medicine now?