the sanguineous sys tem. II. Moving ber in the beginning of his illness above twelve or sixteen powers of in a minute; though he suspects in this and all other instances, where it is below forty, that the artery beats oftener than it can be felt; because such slow pulses are usually unequal in their strength, and some of the beats are so faint as but just to be perceived; so that others, probably still fainter, are too weak to make a sensible impression on the finger. He had attended two patients, who, in the best health, had always very unequal pulses, as well in their strength as in the spaces between them, but which constantly became regular as the patient grew ill, and gave a never-failing sign of recovery in their once more returning to a state of irregularity*. In women women than the pulse is, generally speaking, six or eight strokes in a minute quicker than in men, and hence, many women of firm health and a lively disposition have a standard pulse of eighty-five. Quicker in in men. faney. In a weakly frame the pulse is usually rapid; for debility is almost always accompanied with irritability, and the heart partakes of the general infirmity. In this case, also, from the feebleness with which the heart contracts, the ventricle is but imperfectly emptied, and consequently soon filled again, and sooner stimulated to contraction. Rate in in- Hence, in infancy the pulse is peculiarly quick, and gradually becomes slower as the child increases in strength. Dr. Heberden, who paid particular attention to this subject, estimates the pulse on the day of his birth, and while asleep, from a hundred and thirty to a hundred and forty; and fixes it at little less than the same rate, or that of a hundred and twenty strokes, for the first month. During the first year he calculates it at from a hundred and twenty to a hundred and eight: during the second, at from a hundred to ninety: during the third, from a hundred and eight to eighty, at which it continues for the three ensuing years. In the seventh year it is frequently reduced to seventy-two; and in the twelfth, to In advanced seventy t. In advanced age, from the small quantity of life. powers of neous sys tem. sensorial power secreted, and the general inertness of II. Moving the organs, the pulse sinks often considerably below sixty the sanguistrokes in a minute. "I knew one", says Dr. Heberden, "whose chief distemper was the age of fourscore, in whom, for the last two years of his life, I only once counted so many as forty-two pulsations; but they were seldom above thirty, and sometimes not more than twenty-six. And though he seemed heavy and torpid, yet he could go out in a carriage, and walk about his garden, receive company, and eat with a tolerable appetite." I have at this moment under my care a case of still Singular greater anomaly, in which the pulse is never more than anomaly. thirty, and more commonly even after walking, not more than twenty-seven strokes in a minute. Mr. Alexander, the patient I refer to, is sixty-five years of age; about six years ago, from the bursting of a pipe for the conveyance of coal-gass, he fell down in a fit of asphyxy, from which he revived with great difficulty. The reducent plan was carried too far, and though he has recovered from the accident, and his head is uniformly clear, he is dyspeptic, and subject to palpitations of the heart. The pulse may be counted with great accuracy up to a hundred and forty or a hundred and fifty in a minute; and if the stroke be equal, and the wrist slender, so that we can take in more than half the artery by the pressure of two fingers, we can reach a hundred and eighty; Professor Frank gives an instance of two hundred in a case of complicated carditis; but beyond this there is great confusion and uncertainty: and it is difficult, therefore, to understand by what nice mode of measurement Dr. Wendt could distinguish, as he tells us he has done, a pulse of two hundred and forty-three strokes in a minute†. To what culable by the finger. number cal The pulse is quickened by very slight excitements Quickened both external and internal. The stimulus of the air, of by slight the light, and of sounds, is sufficient to make that of an • De Cur. Hom. Morb. Epit. Tom. 11. p. 175. 8vo. Manhem 1792. excitements. II. Moving powers of the sangui neous sys tem. In like manner ed. infant awake fifteen or twenty strokes more frequent than when it is asleep, and beyond their control. The pulse of an adult is usually quickened eight or ten strokes during the digestion of a meal; and running, or any sudden and rapturous emotion of the mind will double the ordinary scale. The depressing passions, on the soon check- contrary, check it, and have, sometimes, put a total stop to the heart's motion, with a deadly shock, and killed the patient in a moment. There are many drugs that have a like tendency, of which all the simple narcotic poisons afford examples. The digitalis and hyoscyamus are expressly used on account of this property: the prussic acid, and the plants that contain it, as bitter almonds and the leaves of the prunus Lauro-cerasus, when given in free doses, destroy the irritability, and Sometimes extinguish the pulse instantly: and this so effectually that the heart, when immediately examined, has been insensible, not only to puncture, but to concentrated acids. stopped in stantly. How quickened by morbid ex citements. Hence the pulse a no someter. Other circumstances to be no ticed in con nexion with its quick ness. As the excitement of the stomach during the natural process of digestion is capable of accelerating the pulse eight or ten strokes in a minute, there can be no difficulty in conceiving that it may be still more accelerated by a morbid excitement of any other large organ, and particularly where the primary seat of excitement is in the sanguiferous system itself. And as, generally speaking, the frequency of the beat is in proportion to the degree of excitement, the pulse becomes a sort of nosometer, or measurer of the violence and danger of the disease and it measures it equally, whether the return of the beat be below the standard of health or above it. How far, in either case, the pulse may vary from its natural number without great danger, depends upon a multitude of collateral circumstances, as the age of the patient, his idiosyncrasy, the peculiar disease he is labouring under, and the strength or weakness of the system. And hence, in addition to the number of the pulse, we should also attend to its degree of fulness, softness, firmness, freedom, and regularity; a critical knowledge of which can only be learnt by experience and a nice discrimination. II. Moving powers of the sanguineous sys tem. The doc It has been highly injurious, however, to the study of medicine, that this subject has been often too finely elaborated, and the variations of the pulse been ramified trine often into so many divisions and subdivisions, and nice un- rendered too complinecessary distinctions, as to puzzle the young and be of cated. no use to the old. And hence, some of the best pathologists of modern times have been too much disposed to shake off nearly the whole of the incumbrance, and pay no attention whatever to the pulse except in regard to its frequency. Amongst this number was Dr. Heberden: "Such minute distinctions of the several pulses", says he, "exist chiefly in the imagination of the makers, or, at least, have little place in the knowledge and cure of diseases. Time, indeed, has so fully set them aside, that most of these names of pulses are now as unheard of in practice as if they had never been given."* And in forming, therefore, his prognostic of a disease, while he appeals to the pulse merely in respect to its number, he draws his other grounds of decision from the nature of the malady, and the violence of its specific signs. too much But this is to limit the subject to too strict a Sometimes boundary; and to exclude ourselves from what, in many simplified. instances, are clear and even leading diagnostics. There are some practitioners, and of very high merit too, whose fingers are no more capable of catching the finer distinctions of the pulse than the ears of other persons are the niceties of musical sounds. I suspect this was the case with Dr. Heberden, as it was also with the late Dr. Hunter; of whom Mr. John Hunter observes, that, "though he was extremely accurate in most things, he could never feel that nice distinction in the pulse that many others did, and was ready to suspect more nicety of discrimination than can really be found. Frequency of pulsation in a given time is measurable by instruments; smartness or quickness in the * Med. Trans. Vol. 1. p. 20. II. Moving the sangui powers of neous system. Strength and regularity, or weakness and irregu stroke, with a pause, is measurable by the touch, but the nicer peculiarities in the pulse are only sensations in the mind. I think ", continues this distinguished physiologist, "I have been certain of the pulse having a disagreeable jar in it when others did not perceive it, when they were only sensible of its frequency and strength and it is, perhaps, this jar that is the specific distinction between constitutional disease or irritation and health. Frequency of pulsation may often arise from stimulus, but the stroke will then be soft; yet softness is not to be depended on as a mark of health, it is often a sign of dissolution; but then there must be other attending symptoms.' Dr. Fordyce's table of the pulse is, perhaps, unnecessarily complicated; but the strength or weakness, fullness or smallness, hardness or softness, regularity or irregularity of the pulse, are indications nearly as clear as its frequency or slowness, and, in many cases, quite as diagnostic of the general nature of the disease. Frequency and slowness of the pulse taken by themselves, indicate little more than the degree of irritability of the heart, or the force of the stimulus that is operating upon it. The strength and regularity, or weakness and irregularity of the pulse are as palpable to the finger as the preceding signs, and show, in characters nearly as larity of the decisive, the degree of vigour or debility of the heart; pulse. and hereby, except where this organ is labouring under some local affection, the vigour or debility of the system, which a mere variation in the state of the frequency of the pulse will not tell us. A full and a small pulse may be distinguished with almost as much ease as any other property it possesses; this Mr. John Hunter ascribes to the state of the arteries: but, if I mistake not, it gives us rather a measure of the quantity of blood circulating through the system, than of the muscular strength of the arteries, or of the heart itself; which is often a very important indication, and especially when combined with the pre Full and small pulse. • On Blood, Part 11. Ch. iii. p. 318. |