ASTHMA (_____, a gasping, ______, to gasp for breath), a disorder of respiration characterised by severe paroxysms of difficult breathing, usually followed by a period of complete relief, with recurrence of the attacks at more or less frequent intervals. The term is often incor-rectly employed in reference to states of embarrassed respiration, which are plainly due to permanent organic disease within the chest, and which have none of the distinctive characters of true asthma. The onset of an attack of asthma is usually sudden, although there may exist certain premonitory symptoms which warn the sufferer of its approach, such as a feeling of discomfort, drowsiness, irritability, and depression of spirits. The period when the asthmatic paroxysm comes on is generally during the night, or rather in the early hours of morning. The patient then awakes in a state of great anxiety and alarm, with a sense of weight and tightness across the chest, which he feels himself unable to expand with freedom. Respira-tion is performed with great difficulty, and is accompanied with wheezing noises. His distress rapidly increases, and he can no longer retain the recumbent position, but gets up, and sits or stands with his shoulders raised, his head thrown back, and his whole body heaving with his desperate efforts to breathe. His countenance is pale or livid, and wet with perspiration, while his extremities are cold ; his pulse is rapid and weak, and frequently irregular nr intermitting. All his clothing must be loose about him ; he cannot bear to be touched, and the very presence of others around him seems to aggravate his distress. His one desire is to breathe fresh air ; and he will place himself by an open window and sit. for hours in the middle of the night, unmindful of the exposure. His appearance ia alarming in the extreme, and it often seems as if each breath would be bis last. The paroxysm, after continuing for a variable length of time, often extending over many hours, begins to abate, the breathing becomes easier, and the subsidence of the attack is frequently marked by the occurrence of coughing with expectoration. When the expectoration is abundant the asthma is called humid, but where there is a little or none it is termed dry. After the cessation of the attack the patient appears to be and feels comparatively well. In cases, however, of long standing the subject of asthma comes to bear permanent evidence of its effects. He is easily put out of breath on exertion and he requires to lie with his head elevated, circumstances to be ascribed to organic changes in the chest, which oft-recurring attacks of asthma are liable to induce. The asthmatic paroxysms, although occasionally periodic, do not generally observe any regularity in their return. They may recur each successive night for several days, or there may be no return for many weeks or months, this being to a large extent dependent on a renewal of the exciting cause. Asthma is much more common in men than in women. In may be developed at any age, but is most fre-quently observed in early and middle life. A large number of cases take their origin in diseases affecting the respiratory system during infancy, such as hooping-cough, measles, and bronchitis. Asthma is often hereditary, and in all cases one attack appears to predispose to others.

With respect to the pathology of asthma, it is now gene-rally held that the essential nature of the disease consists in a spasmodic contraction of the bronchial tubes. This ia due to some deranged condition of the nervous system, affecting, either directly or by reflex action, the nerves supplying the contractile fibres lining the bronchi and regulating their calibre. The bronchial tubes being thus spasmodically narrowed, and losing for the time their expansile power, air can only, with the utmost difficulty, be got into or out of the chest. In these circumstances the muscles of the trunk concerned in respiration are called on to act with great violence to expand the chest, but with little avail, and hence the distress and threatened suffoca-tion. But while asthma is thus to be regarded as essentially a nervous ailment, its occurrence, apart from some organic disease in the chest or elsewhere, is admitted to be com-paratively rare. Some cases, however, appear to be of purely nervous origin. To these the term Nervous or Spasmodic Asthma is applied, and it is more particularly to this form that the symptoms above narrated refer. In such cases no actual disease can be discovered with which the asthma could be directly connected. Attacks of this nature appear capable of being excited in those subject to them in very various ways. Thus violent emotions are not unfrequently the cause of asthmatic paroxysms. The effect of the inhalation of certain effluvia in exciting attarjes of asthma is undoubted, as in the familiar instances of the odour of hay and of ipecacuan. In no particular is the eccentric character of this disease more remarkable than in that of locality. Changes of air, otherwise inappreciable, may give occasion to the most severe attacks of asthma, as. on the other hand, they may be the means of accomplishing a cure of the disease where it exists. Circumstances, ap-parently the most trifling, have been known to give rise to severe paroxysms of asthma, as the extinguishing of 8 light in a sleeping apartment or the shutting of a door o But asthma is very frequently associated with some form of chest complaint, more particularly bronchitis, and hence the term Bronchitic Asthma. The relation between the two ailments in such cases is rendered sufficiently obvious by the fact that the one does not occur without the other; and it is evident that Che irritation of the bronchial mucous membrane gives rise by reflex nervous action to narrowing of the tubes. When the bronchitis is cured the asthma disappears. Asthmatic-like paroxysms are also of occa-sional occurrence in some forms of heart disease, and the term Cardiac Asthma is used to describe such cases. They can, however, scarcely be regarded as cases of asthma, but rather as attacks of difficult breathing referable to some impediment to the pulmonary circulation, the result of the heart disease.

The treatment of asthma consists in the employment of remedies to allay the paroxysms, and in the adoption of measures likely to prevent their recurrence. During the attack the patient should be placed in as favourable circumstances for breathing as practicable. He usually selects the position easiest for himself. Abundance of air should be admitted to the apartment, and he should be interfered with as little as possible. The remedial agents employed with the view of relieving the paroxysms are very numerous, and only a few of the more important of them can be alluded to. Opiates administered internally or hypodermically are of known efficacy, as is also the inhalation of anaesthetic vapours. Much value is attached by many to the smoking of stramonium, and even tobacco smoking appears in some instances to give relief. The fumes of nitre-paper (blotting-paper prepared by being dipped in a saturated solution of nitre and dried) burnt in the apartment often succeed in mitigating the paroxysm. The use of the tincture of Lobelia inflata is recommended by many high authorities, as are also the employment of emetics, the latter more especially where the attack can be traced to errors in diet. None of these remedies, however, ought to be tried without medical advice. Coffee is a popular and useful remedy, but to do good the infusion must be very strong, and taken upon an empty stomach. To prevent the recurrence of the paroxysms special care must be taken by the sufferer to avoid those influences, whether connected with locality or mode of life, which his experience may have proved to have been the occasion of former attacks. Where the paroxysms are of periodic occurrence the use of quinine or arsenic has been tried with good results. (J. O. A.)