ASTHMA, as'ma, or az'rna, a disorder of respiration characterized by more or less severe paroxysms of difficult breathing accompanied by coughing, wheezing and, in severe attacks, by slight asphyxia. The attacks usually come on suddenly, last from a few minutes to many hours and are generally followed by complete relief, and recur at more or less frequent in tervals. They are characterized by extreme difficulty both in inspiration and expiration. Numerous theories have been advanced in regard to the causation of the disease, but the symptoms are best explained by ascribing it to a spasmodic contraction of the muscles of the bronchioles (small bronchial tubes). The underlying causes of this are manifold, but there are a few which are of special import ance and attention to these may help greatly in avoiding or lessening the severity of the attack. The predisposition of asthmatics is usually a hypersensitive nervous system or an irritable nasal mucous membrane, or the at tack may be started by some external irritant. Asthma occurs oftener in men than in women, and frequently in children, especially after bronchitis, measles or whooping cough. It may occur in any climate or locality, in the mountains or at the seashore. A change of air or of locality is an important factor in some cases. The affection is most common during spring and autumn, which may be due to the larger amount of dust and pollen in the air at inherited, seasons. The malady is often times nherited, passing from one generation to another; statistics show this to be true in 50 per cent of the cases. Gout and rheumatism are causes frequently associated with the dis ease. Among reflex causes are constipation, indigestion, uterine disturbances, nasal catarrh and growths of the nose pressing upon the septum higher up. Touching certain spots in the nose causes some persons to sneeze and may excite a paroxysm; pregnancy has been recognized as causing asthma in some cases. Disorders of the heart and kidneys produce respectively cardiac and renal asthma. Dust, fog, pollen, sulphur from matches, emanations from horses, cats, dogs, etc., fumes from cer
tain chemicals are all external irritants which may cause an attack in a person constitution ally predisposed. Physical excitement, anger, grief, etc., are also causes. Asthma is never i due to disease of the lungs and is never directly associated with tuberculosis. Some times cases occur with no apparent cause to account for the onset of the symptoms.
The symptoms may come on at any time during the day or the night, but in the majority of cases the attack begins during the night, sometimes abruptly but often by degrees. A sense of marked fatigue, sneezing or heavi ness in the pit of the stomach are signs which the patient soon learns to recognize as the forerunners of an approaching attack. He is aroused from sleep after midnight with a choking sensation. In some cases this condi tion increases slowly, not becoming acute for an hour or more. In sudden, severe attacks the patient springs from bed and rushes to an open window for air or else he will place himself in a chair and try to get into a position most comfortable for breathing. Most asth matics have some special attitude which best enables them to use all the auxiliary muscles of respiration and which they assume at the onset of the attack and keep until it begins to subside. The face becomes pale and anx ious, the voice is gasping and speech is diffi cult, the eyes bulge and the face becomes cya notic as the paroxysm continues; cold clammy perspiration covers the face, breathing becomes more difficult and laborious as the chest is now expanded and the expiration of air is very much prolonged. This breathing is ac companied by wheezing sounds upon the chest. The attack may last from one hour to several days; it subsides gradually, the patient begins to cough and rids his lungs of some frothy mucus in which is mixed grayish-white masses; he then feels greatly relieved, the color returns to his face, and he goes off into a sound sleep from which he awakens feeling greatly re freshed. A patient rarely, if ever, dies during i a paroxysm as it is of spasmodic character, and once over it, he quickly regains his normal condition.