On examination of the chest during an attack we find general hyper resonance of the percussion note ; the vesicular murmur is either very fee ble or completely suppressed, and is often quite covered by large sonoro sibilant rhonchus. At the base copious subcrepitant riles may be heard.
The attack lasts for a variable time. It usually continues more or less severely for two or three days, and then gradually subsides. As a rule, the more severe the dyspnma, the shorter its duration ; but for days or even weeks after the attack is over the child may wake up wheezing in the morn ing, and his breath may be short for some hours after rising from his bed.
Sometimes the onset of the attack is heralded by severe coryza, with re peated sneezing, and this is quickly followed by distressing dyspncea. The oppression of breathing seems sometimes to threaten actual suffocation and in all cases the severity of the suffering from want of air is out of all pro portion to the insignificant character of the physical signs. The seizure, however, invariably ends in recovery. After a time the breathing becomes easier, and eventually all distress is at an end ; but before the termination of the attack is reached there may be many alternations in the intensity of the dyspnoea, and even after the days have become peaceful the nights may still be disturbed by a return of the paroxysms.
Diagnosis.—In cases of paroxysmal dyspncea it is important with regard both to prognosis and treatment to ascertain the exact cause of the dis tressing symptom.
When the clyspncea is due to occlusion of the larynx from spasm, from impaction of a foreign body, or from the pressure of a retro-pharyngeal abscess, the difficulty lies chiefly in inspiration. As each breath is drawn the soft parts of the chest sink in and the epigastrium is deeply retracted. The inspiration is excessively long and laborious, the expiration short and comparatively easy. At the same time crowing sounds are produced in the glottis and point unmistakably to the seat of the impediment.
In cases where the hindrance to respiration is seated at a lower level, as when a main bronchus is obstructed by a foreign body, or the trachea at its bifurcation is compressed by a mass of swollen glands, and also in cases of bronchial asthma, the distress is chiefly seen in expiration, which is prolonged, laborious, and ineffectual. Attacks of dyspucea from these causes require to be very carefully discriminated, as they are all commonly spoken of as " asthmatic attacks." The most frequent of these in children, beyond all comparison, is enlargement of the bronchial glands ; and most cases of "asthma " in early life are due to direct pressure by swollen glands upon the air-tubes. Scrofulous children are very sensitive to chills and readily take cold. They are consequently frequent sufferers from pulmo
nary catarrh. In these attacks the glands undergo a rapid temporary in crease in size, and their enlargement may set up serious pressure upon the windpipe at its bifurcation.
Dyspncea from this cause is often intense, and comes on in violent par oxysms which usually occur at night. The character of these seizures has been elsewhere described (see page 182). In such cases there is not al ways dulness at the upper part of the sternum, or between the scapulae ; for alteration of the percussion-note can only be noticed in cases where the swollen glands are in contact with some part of the chest-wall. The chief collection of bronchial glands lies in the bifurcation of the trachea ; but others are distributed along the course of the bronchi as far as the third or fourth subdivisions. Enlarged glands, therefore, may be found after death deep in the substance of the lung, as described by Cruveilhier. The effect of enlargement of these bodies is to press upon and flatten the air-passages ; and if the calibre of the tube be at the same time lessened by viscid secre tion, the channel for the time may be completely occluded. By such means the most serious clyspnom may be produced.
A little girl, between three and four years old, was said to be subject to feverish attacks which lasted from a few days to a week. In these the child first showed symptoms of catarrh and then began to suffer from urgent dyspncea. In the last of these attacks, as described to me, the breathless ness began quite suddenly at night and woke the child up from her sleep. She was said to have started up gasping in the utmost distress, and her voice was hoarse. After about an hour the paroxysm subsided and the child had a violent attack of spasmodic cough, retching up much phlegm. The seizures were repeated for six nights in succession, becoming, how ever, less severe towards the end of this period. In the daytime the pa tient seemed fairly well, although towards evening her breathing would be a little short. Her nose also bled a great deal. This little girl was brought to me some time after the last attack had subsided, when she had returned to her usual health. The jugular veins on each side of the neck were then noticed to be full, and the venous radicles on the front of the chest to be unnaturally visible. There was a suspicion of duhiess on the upper bone of the sternum, and when the child bent her head backwards a venous hum was heard at that spot, ceasing when the chin was again depressed. The lungs did not appear to be emphysematous, nor was there any dulness at either apex ; but the breath-sounds were very loud and hollow at the su pra-spinous fossee, especially in expiration.