Commentaries on the Surgery of the War in Portugal, Spain, France, and the Netherlands / from the battle of Roliça, in 1808, to that of Waterloo, in 1815; with additions relating to those in the Crimea in 1854-55, showing the improvements made during and since that period in the great art and science of surgery on all the subjects to which they relate.

by G. J. Guthrie

297. In order to understand, or to become in any way acquainted with the changes from the natural structure which are going on under derangement in the chest, even from simple injuries, it is always necessary to have recourse to auscultation, and sometimes, although more rarely, to percussion, if the external parts are not too tender. Under all circumstances both sides of the chest should be examined by the stethoscope. As the ordinary breathing of an individual is rarely sufficiently strong to enable the auscultator to hear it with distinctness, the patient should be desired to inspire fully and more quickly than usual, without much effort, and without noise from the mouth or nose, or retaining his breath. The inspiration and the expiration are both to be carefully observed.

When the ear is firmly and equably applied to the chest of a healthy young person, a very distinct and long-continued sound is heard at the moment of inspiration, and another at that of expiration. This is called the vesicular or respiratory murmur, and is dependent on the air fully permeating and distending the air-vesicles of the lungs. It has been poetically compared to the sound of a gentle gale rustling in a thick summer foliage—to the whisper of a retiring wave on a sandy beach in a calm day. It is soft, scarcely sonorous, equable, and during inspiration continuous. In childhood it is louder than in adult persons, arising probably from the greater activity of the lungs in young than in elderly people. This is called, and especially when perceptible in adults, puerile respiration, as opposed to their ordinary, or what in old persons may be called senile. It is more marked during inspiration.

When the stethoscope is applied in the situation of the great bronchial passages, as over the first bone of the sternum, under the clavicle, in the center of or between the shoulder-blades, a different sound is usually but not always distinguishable, when the patient breathes fully, arising from the passage of the air through these bronchial tubes. It is compared to the noise made on blowing through a reed or quill, and is called bronchial or tubular respiration. When heard in other parts of the chest, it is a morbid sound. If the stethoscope be applied over the trachea, the sound is louder, rougher, and more intense, and is called tracheal respiration. On listening over the trachea during speaking, the voice sounds as if it were passing into the ear, and the words are distinct—tracheophony. This, if heard in any other part of the chest, is a sign of disease, for in the natural state the voice is heard only to resound through the chest, but the words are not heard if the other ear be stopped. When heard, the sound has been called pectoriloquy, and is supposed to imply the existence of a cavity at that part; but the word is unnecessary, or, if used, it means that the cavern or hollow communicating directly with the trachea gives forth a similar or nearly similar sound, a natural sound in an unnatural position. The essential difference between bronchophony and tracheophony in the investigation of disease is, that in the latter the voice apparently speaks through the stethoscope into the ear of the auscultator, while in the former it is heard with scarcely less distinctness, but at the distal end of the instrument. Over the larynx it is louder, hoarser, and rougher.

The length of the sound in inspiration, as compared with that of expiration, has been said to be as five to two. One is louder and longer than the other, a difference requiring attention from the circumstance that morbid sounds of great import are heard in inspiration, which do not prevail during expiration. When any other difference is perceptible between them, so that they more nearly resemble each other in duration or in intensity, or when expiration is prolonged, some structural alteration may be suspected in old persons, some disease in young ones. When little or no respiratory murmur can be heard after symptoms of inflammation have existed for some time, the case is very serious, implying that effusion into the cavity, or condensation of the lung, has taken place to a considerable extent.

298. The number of inspirations in a minute in the adult and elderly persons varies from eighteen to twenty-two in a state of health: from twenty-two to twenty-six in children. The stroke of the pulse is generally as four to one. If the inspirations are eighteen, the pulse will in general be seventy-two. Both may be slower, although they are often quicker under disease. When the breathing is slower, it commonly indicates some affection of the nervous system; when very rapid, some important lesion within the chest.

The theory of percussion is founded upon three elementary sounds, which are produced when a solid, a liquid, or a gaseous body is struck; all others are varieties of these. The sensation of resistance which is experienced at the same time bears an exact relation to the density of these bodies—hence the resistance when a solid substance is struck is greater than when a gaseous one is under percussion. The liver, the thorax in a case of pleuritic effusion, and the distended stomach after a long fast, afford good examples of these elementary sounds. To employ percussion successfully, it is necessary that the strokes be uniform in force and quickness, and that the finger or pleximeter be so applied to the surface that no space exists between them, otherwise such a sound will be elicited as may give rise to an incorrect diagnosis.

It having been stated that a sound lung never fills the bag of the pleura, particularly toward the diaphragm, at least during ordinary respiration, I requested Mr. Quekett, the Resident Conservator of the College of Surgeons, to ascertain this by experiments on some sheep at the moment of their being killed; and it appeared from them that the base of the lung is always in contact with the surface of the diaphragm.

299. In ordinary expiration the chest diminishes in size. The ribs which have been raised recede, by the elasticity of their cartilages, and by the return of the ligaments, to their state of rest; the elevated muscles become relaxed, while others belonging to the lower part of the trunk and abdomen contract. The diaphragm is relaxed, and pushed upward by the viscera of the abdomen, pressed upon by the muscles of its wall, if it should not be drawn upward by the attraction of the lung, which when distended endeavors by its elasticity to return upon itself, and to occupy less space than the capacity of the chest will afford. The lung, invested by an elastic, special, and transparent membrane, and covered by the pleura pulmonalis, is composed of an immense number of air vesicles, the largest being equal in size to the fourth part of a millet-seed. These air vesicles, crowded together, each communicating with a fine bronchial tubule, are separated from each other into groups by a condensed cellular tissue, thicker where it surrounds these lobules, which alternately form, when aggregated together, a lobe, whence it is called interlobular tissue. An artery and vein form a very minute net-work around each vesicle. These vesicles may become filled with water; when dilated by air, they constitute what is called emphysema of the lung. The lung in man is constantly applied to the internal surface of the chest, the pleura or serous membrane covering the lung being closely applied to the pleura lining the wall, and one surface glides upon the other, moistened by a secretion in just sufficient quantity to effect this object. If the lower intercostal muscles of a young animal be removed to a sufficient extent, the lung and the diaphragm may be seen applied to the inside of the pleura lining the rib, and ascending and descending in concert, the lungs moving vertically, not horizontally. The diaphragm ascending, covered by its pleura, is in a similar manner applied to the lower part of the wall of the chest, which had been filled by the lung during inspiration. After death the lung remains closely applied to the pleura, recedes on an opening being made into that membrane, and may collapse, provided no adhesions exist to prevent it.

300. When inflammation of the pleura takes place, the gliding motion is not effected silently, but with a peculiar noise, called by the French frottement. When the lung is inflamed, the respiratory murmur is changed in that part, or is overcome by a peculiar sound, which can be distinctly investigated by the ear—rhonchus crepitans. Hence the great value of auscultation.

In the following observations it is not intended to give a history of, or even the whole of the symptoms and consequences of inflammation of the pleura and the lungs; but only to draw attention to such of the principal facts as it may be necessary to consider when these inflammations and their consequences are caused by external injuries.