Sooner or later aneurism shows itself externally by wearing away the ribs, and forming a pulsating tumor on the front of the chest, or by pulsation, which can be felt when the finger is pressed deeply behind the sternum or clavicle, except in the case of the descending aorta, when it sometimes produces no symptoms upon which reliance can be placed : slight dysphagia or dyspncea, with pain in the back, caused by pressure and wasting of the vertebrae, some times leading to paralysis, may be the only symptoms: no bruit is usually audible in this situation ; but would be of considerable significance if heard in an adult ; in the child, cardiac murmurs are often very loud over the back. Solid tumors in the chest do not often pulsate, but the possibility of pulsation being only communicated should be borne in mind in attempting to discrimi nate their character.
Tumors in connection with the bones of the chest seldom oive rise to any likely to call for examination, until there is swelling externally: those forming in the anterior mediastinum, which cannot find exit from the chest, and press inwards on the heart, the arteries, the veins. and the bronchi, do, however, produce symptoms more or less resembling those of pressure on the root of the lung. The very marked dulness which they cause on perces*. ing the sternum leads at once to the recognition of their presence ; and the question is then only between enlarged heart or aneurism, and growth from bone.
The coexistence of active pleurisy, or of passive effusion into either pleura, sometimes greatly complicates the diagnosis of thoracic tumors.
§ 11. Hooping-cough.—As in many other diseases in which the group of symptoms is better known than the nature of the internal lesion, hooping-cough, when well marked, cannot be mistaken; and diagnosis has only to do with those cases which are obscure, because the whoop is imperfectly developed, or because the disease is simulated by or complicated with other affections. Simple catarrh of childhood may very readily pass into hooping-cough if it be at the time prevailing epidemically: in such circumstances we may reasonably conclude that it is only the precursor of such an attack when the cough is at all parox ysmal, or is as urgent or an early symptom, and when the fever 1/11 slight, and there is but little derangement of health, and espe cially when auscultation fails in detecting bronchial irritation proportionate to the severity of the cough. When the disease is fully formed, if a paroxysm occur in our presence the case can scarcely be mistaken ; but we must often trust to the report of others; and there is a tendency to error in listening to the state ments of mothers and nurses, who usually anticipate us in the conjecture of its possible presence, and are disposed at once to attribute any peculiarity in the child's cough to this cause. A very good indication is obtained in cases where the account of the paroxysm is defective, from the occurrence of vomiting, which is very common in this disease after a fit of coughing, while in other affections of the chest such an event is unusual : in the one case it is caused by the cough, without sickness or loss of appetite, and the child will take his food directly afterwards ; in the other, the stomach and bowels must be disordered, and the relation to the cough is fair less evident.
In the early period of an attack of alleged hooping-cough, the presence of much bronchial secretion should make us cautious in accepting the statement of the friends as to the nature of the dis order ; similar caution is necessary when the disease is said to have attacked a child who has been long suffering from cough before anything like a whoop was observed. In its latter stages there is usually much bronchial secretion, and the disease is fre quently complicated by inflammation of the lung or effusion into the ventricles of the brain ; in very protracted cases it may terminate in the development of tubercle : diagnosis must then take account not only of the present symptoms, but of the history at a time when the characters of the affection were simple and unmixed with those of subsequent complications. An ill-deve loped child in whom an attack of bronchitis is attended with excessive secretion, or one whose lungs are becoming stuffed with tubercles, when the secretion is scanty and adhesive, are each of them very liable to fits of coughing, in which, while there is no real whoop, the struggle for breath is very analogous to the abortive paroxysms which occur before whooping-cough is fully developed.
§ 12. Diseases of the Lungs in Childhood.—This chapter would be incomplete, if a few words were not said upon the differences in diagnosis between the diseases of children and those of adults. In the first place, the resiliency of the chest makes the indications from percussion much more obscure and uncertain ; at one time dulness seems to be well marked, which, after all, is only due to congestion ; at another, real consolidation produces only a differ ence in tone, which cannot properly, be called dull. Secondly, the respiratory sound is so much louder and shriller, that changes in character, except in its relative suppression, cannot be predi cated of it with anything like the same certainty as in adults. Thirdly, the loudness of the voice does not assist us much in de termining the sound-conducting power, and hence the degree of consolidation of the lung. And fourthly, the remark in regard to superadded sounds in adults, that no one is pathognomonic of any certain condition of lung, is infinitely more true of children. Crepitation, in its true sense, is not heard in pneumonia, clicking and squeaking sounds are heard when there are no tubercles, and gurgling noises are heard without cavities. The explanation of all these circumstances is simply that in the lungs of the child every sound generated anywhere throughout the lungs is beard with almost equal distinctness at any part of the surface; and therefore, whatever the affection may be, the bronchial sounds prevail; at the same time the mucous membrane is more easily irritated, and secretion excited by slighter causes; and hence it happens that sonorous sounds are very seldom present.