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tions that may be put to him. His back is rounded and his gait stooping ; indeed, his whole figure is deformed. His chest, back, shoulders and head are fixed; he cannot even turn his head from side to side, but when he looks from object to object merely turns his eyes, like a person with a stiff neck ; his shoulders are raised to his ears, and his head thrown back and buried between them. In order the better to raise his shoulders, and at the same time spare muscular effort in doing so, his elbows are fixed on the arms of his chair, or his hands planted on his knees, or he leans forward on a table, or sits across a chair and leans over the back of it, or he stands grasping the back of a chair and throwing his weight upon it,* or leaning against a chest of drawers or some piece of furniture sufficiently high to rest his elbows on in a standing position. At every breath his head is thrown back, his shoulders still more raised, and his mouth a little opened, with a gasping movement; his expression is anxious and distressed ; the eyes are wide open, sometimes strained, turgid, and suffused ; his face is pallid, and, if the dyspnoea is extreme and long, slightly cyanotic; the labour of breathing is such that beads of perspiration stand on his forehead, or even run in drops down his face, which his attendant has constantly to wipe. He is so engrossed with his sufferings and the labour of breathing, that he seems unconscious of what is going on around him; or else he is impatient, and intolerant of the assiduities of those who are in vain trying to give him some relief.

If the bronchial spasm is protracted and intense the temperature falls; the oxygenation of the blood is so imperfectly performed, from the sparing supply of air, that it is inadequate to the maintenance of the normal temperature; the extremities especially get cold, and blue, and shrunk; I have known the whole body deathly cold, and resist all efforts to warm it, for four hours. But while the temperature is thus depressed, the perspiration produced by the violent respiratory efforts may be profuse, so that the sufferer is at the same time cold and sweating. It is this union of coldness and sweat, combined with the duskiness and pallor of the skin, that gives to the asthmatic so much the appearance of a dying man, and that even sometimes makes the initiated fear that death is impending.

The pulse during severe asthma is always small, and small in proportion to the intensity of the dyspncea; it is so feeble sometimes that it can hardly be felt. The explanation of this is very simple. The imperfect supply of air produces capillary arrest-partial stasis-of the pulmonary circulation; but a small quantity of blood is therefore allowed to pass on to the left side of the heart, so that the volume on which the left ventricle contracts, and which it impels into the arterial system at each pulsation, is extremely small, and barely sufficient to register itself at the wrist. That the small pulse is due to pulmonary capillary arrest, itself due to the shutting off of air from the lungs, is proved by the fact that immediately the paroxysm yields, the pulse resumes its normal volume. I have never known the small pulse absent in severe asthma; its very explanation proves that it could not be. • I have known a patient stand in this position for two days and nights, unable to move,

One curious symptom of asthma, which I have found present in a large number of cases (I am not sure it is not universally present), but which I have never seen uoticed in any treatise on the subject, is itching under the chin. I have often known that the breathing of asthmatics was tight, and told them so, from seeing them scratching and rubbing their chins. The itching is incessant, and of an indefinite, creeping character, but although it is impossible to help scratching it, the scratching does not relieve it. It is often accompanied with the same itching sensation over the sternum and between the shoulders, especially between the shoulders. It appears the moment the first tightness of breathing is felt, and goes off when the paroxysm has become confirmed—indeed, I think it is more pronounced in those slight and transitory tightenings of the breathing to which asthmatics are so liable (as, for example, after laughing), than in regular attacks. But I think it is the most strongly marked of all in the asthma that accompanies hay-fever. The sternal and interscapular portion of this itching is, I think, of easy explanation, its distribution to the chin is less easy to understand. According to the law that the pain arising from the irritation of a viscus shall be referred to the superficies, front and back, in the middle line and at a level with the viscus (a law illustrated by the seat of the pain in stoniach, bowel, and uterine disease), the seat to which the sensation from bronchial irritation is referred is the sternum and between the blade-bones. Thus, in bronchitis, the raw, scraping feeling that accompanies cough is sternal and inter-scapular; so that in relation to this asthmatic itching, the fact would appear to be simply this —that while the impression on the bronchial nervous system produced by inflammation of its mucous membrane gives rise to sternal and interscapular pain, that produced by spasm of these tubes gives rise to sternal and interscapular itching. The itching of the chin must, I think, be of the same reflex character, and admit of the same explanation, but the reason of its locality is less apparent.

On stripping an asthmatic in the height of a paroxysm, an admirable example is seen of the immense array of muscles that become, on an emergency, accessory to respiration, and some idea is formed of the toil of the asthmatic, and the extremity of those sufferings that necessitate for their relief such intense labour. All the muscles passing from the head to the shoulders, clavicles, and ribs are rigid, and the head is rendered a fixed point from which they can act on their respi. ratory attachments. Ordinarily these muscles, such as the splenii and scaleni, have their inferior attachments fixed, and move the head and neck, but now their upper attachment is fixed, and from it they act as mediate or immediate elevators of the ribs and distenders of the thoracic cavity; and this is how it is that the asthmatic is incapable of moving his head. By the contraction of the trapezius and levator anguli scapulæ, the shoulders are raised to the ears, in order that the muscles proceeding from the shoulders to the ribs may act at an advantage as elevators of these latter. The muscles of the back are so engaged in respiration, that they cease to support the trunk, and the gait becomes stooping. At every inspiration the sterno-mastoids start out like cords, and produce by their sudden prominence a deep pit between their sternal attachments. I have already referred to the gaping descent of the lower jaw at each inspiration. Now, what is the explanation of this? What is its mechanism ? I think the rationale of it is this : by its endeavours to raise the scapula, the homo-hyoid muscle is strongly contracted at each inspiration, but its hyoid attachment being by far its most moveable extremity, the contraction of the muscle tends rather to draw the hyoid bone down than to elevate the shoulder; and as the elevators of the hyoid bone—the mylo-hyoid, genio-hyoid, and digastric-are firmly contracted with the view of fixing it, the drawing down of the hyoid bone also draws down the jaw, and thus is produced the descent of the jaw at each inspiration; so that this gasping movement really depends on one of the depressors of the hyoid bone being, by virtue of its scapular attachment, also an accessory muscle of respiration, and being at the same time, from the loose and floating character of its superior attachment, unable to effect that interchange of its fixed and moving points that takes place with regard to the other extraordinary muscles of respiration. In the case of other accessory muscles of respiration, either extremity can be made the fixed one, and thus render the action of the muscle respiratory or non-respiratory, according to circumstances; if the lower extremity is fixed, as is ordinarily the case, the head or neck is moved, and the muscle is non-respiratory; if the upperextremity is fixed, the shoulders or ribs are raised, and the muscle is respiratory. But the upper attachment of the homo-hyoid not being firmly fixable, the muscle cannot transfer its contractions to its respiratory extremity, and thus, though theoretically, it is not actually a respiratory muscle. This explanation, if correct, is not uninteresting, as it offers an example of the maintenance of a type of action in spite of disturbing circumstances that necessarily make the action inoperative; it is an instance, if I may so express it, of morphological physiology, bearing the same relation to function as the retention, in obedience to type, of superfluous or modified appendages does to structure. I am not sure that the other depressors of the hyoid bone do not share in the action.

Meantime all the muscles that increase the capacity of the chest are straining their utmost and starting into prominence at each inspiration; as each breath is drawn every muscle is thrown out into bold relief, and since there are hardly any muscles of the trunk that are not mediately or immediately respiratory, the whole muscular system of the trunk may be mapped out in every part of its detail. The straining muscles are rendered all the more conspicuous from asthmatics being generally so thin.

But violent and laborious as are these respiratory efforts, they are abortive; although the muscles that should move the parietes of the chest are contracting to their utmost, no corresponding movements take place—the chest is almost motionless, its walls are fixed as in a vice, as if they could not follow the traction of their muscles; and this 47-XXIV.

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is really the case. This immobility, in spite of the violent action of the moving agent, is one of the most singular and striking appearances of asthmatic breathing. How different from the wide range of movement that follows even less considerable respiratory effort in one to and from whose lungs the ingress and egress of air is free !

One result of these straining efforts to fill the chest is a permanent distension of it-its walls are kept fixed in a condition of extreme inspiration. So great is this enlargement of the chest during the paroxysm, that a waistcoat that would ordinarily fit cannot be brought together by two inches. But the chest is enlarged in every way, the diaphragm therefore descends, the abdomen therefore seems fuller, and its girth is increased. This, I believe, is the principal cause of that abdominal distension of which asthmatics complain, and which is generally assigned to flatulence. As soon as the paroxysm goes off, the chest and abdomen resume their original size. I do not see that anything is gained by this distension of the chest; the only difference is that the volume of air locked up in the chest is rather larger, but no more is changed at each respiration, and it is the amount so changed, and not the quantity contained in the lungs, that relieves the demand of respiration. Air is the thing that is wanted, and inspiration is the act that ordinarily relieves that want: this keeping the chest, therefore, at a condition of extreme inspiration must be looked upon as an instinctive, but blind and abortive effort to remedy that which is irremediable.

Such being the external phenomena of the breathing of asthmatics, what are the auscultatory sounds that accompany it? They are exactly such as we should expect-exactly such as are consistent with these external phenomena, and such as imply, if the spasm is severe, an almost impassable bar to the ingress and egress of air. On applying the ear to the chest we hear-respiratory murmur none; and this is not because it is drowned by other sounds; if no other sounds are present it is equally inaudible; it is because the conditions of its production do not exist, because sufficient air is not admitted to generate it; just as there is no respiratory murmur in the long-drawn inspiration of hooping-cough, or beneath thoracic parietes fixed by pleurisy or intercostal rheumatism. And this suppression of the ordinary breathing sound is a proof of the depressed standard at which respiration is being carried on, and of the completeness with which air is locked out of and into the chest. The sounds that are heard are dry tube-sounds, large and small-rhonchus and sibilus of every variety, of every note and pitch, and in all parts of the chest, converting it into a very orchestra; but the sounds are mostly sibilant, high and shrill, resembling the chirping of a bird, the squeaking of a mouse, or the mewing of a kitten. And this smallness of sound makes me think that it is almost exclusively the smaller tubes that are the seat of the constriction, whilst the diffusion of the sounds all over the chest shows that constricted tubes exist everywhere.

There is one other fact, in relation to the sounds of asthma, that I think is instructive, and that seems to me to imply that the points of stricture are constantly changing their place, that spasm is constantly

grant that

disappearing in one part and making its appearance in another, and that fact is, that the sounds are continually changing their character and site. On listening over a part of the chest where a few minutes before you heard a loud shrill sibilus you find it gone, while a part that just before was silent is the seat of a chorus of piping. Now, if the sounds were of a moist character, if they were caused by mucus,

I such an inference could not be drawn, for sounds so caused may be, and constantly are, suddenly removed by cough, or other dislodgment of the accumulated secretion; but in the early part of an attack of uncomplicated spasmodic asthma there is no accumulation of mucus in the air tubes—they are dry; the narrowing of the tube, therefore, that gives rise to the musical sound, being solely dependent on bronchial spasm, solely admits of removal by the relaxation of that spasm; and the frequent cessation and change of place of the pipings shows that the spasm that causes them is transient and wandering.

The auscultation, then, of the asthmatic shows us these things: a. The almost perfect stagnation of air in the chest, in spite of the

violent respiratory efforts. B. That the tubes affected are generally very small. 7. That tubes in all parts of the chest are simultaneously affected. &. That the points of constriction are constantly changing place.

ART. IV. On the Effects of Rupture of the Internal and Middle Coats of Arteries.

By GEORGE SCOTT, M.D., Southampton, formerly one of the

Physicians to the British Hospital at Renkioi, Dardanelles. The following causes of arterial obstruction are usually enumerated :viz., 1. Acute inflammation of the artery, or arteritis. 2. Rupture of the internal and middle coats. 3. Degenerations of the arterial coats, such as ossification, calcification, &c., of such a degree as to cause great rigidity of the vascular walls, and great diminution in the calibre of the artery. 4. Coagula or pieces of valves, &c., becoming loosened from the central organ of the circulation—the heart, or from the internal surface of some of the larger arteries, and conveyed to, and impacted in, a more distant arterial canal. 5. Coagula which have formed in the veins, have become loosened thence, been carried into the right cavities of the heart, and ultimately propelled into some of the branches of the pulmonary artery.

As regards the first cause usually assigned for arterial obstruction, it seems to me that the experiments made by Professor Virchow in 1847, and detailed in his collected Memoirs,' at p. 395,* satisfactorily prove that simple acute inflammation of the arterial walls is not alone sufficient to cause coagulation of the blood in the vessel at the inflamed part; and the experiments described below also show that inflammation of the arterial walls of such a degree as to cause great thickening of the latter, is unattended with coagulation of the blood in, and consequent obstruction of, the vessel. The proper subject of this paper, however, is with the second of the

* Gesammelte Abhandlungen zur wissenschaftlichen Medicin, pp. 395-400.

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