Thoracic cavity

“ The intercostal muscles, or those between the ribs, also exert a very considerable influence in raising the ribs during inspiration, and thus increasing the size of the thoracic cavity; and if these be prevented from performing their natural functions, breathing must be carried on solely by the action of the diaphragm, as we find to be the case in almost every instance of consumption or thoracic disease. ”

“ We may perhaps discover a point of flatness at the base or about the centre of the lung, but often this flatness is very incomplete, because the collection of pus does not always reach the thoracic wall. It may, indeed, be separated from it by healthy lung-texture. Auscultation may discover coarse râles or even gurgling with cavernous respiration. The voice sometimes has the character of pectoriloquy, at other times of bronchophony: the cavity is rarely large enough or the walls sufficiently firm to give the amphoric tone. ”

“ When, in addition to the natural opening of the glottis, a false opening is made in the side at the point K, the air within the lung at I, and external to it in the now open pleural cavity, will stand in equilibrio; the lung will collapse as having no muscular power by which to dilate itself, and the thoracic dilator muscles will cease to affect the capacity of the lung, so long as by their action in expanding the thoracic walls, the air gains access through the side to the pleural sac external to the lung. ”

“ By compressing the thoracic viscera, through the operation of an emetic. The beneficial results which frequently attend the concussion of an emetic, in cases of mucous accumulations in the lungs, are too well known and understood to require much elucidation: in the act of vomiting the thoracic viscera are violently compressed, the neighbouring muscles are also called into strong action, and both expiration and inspiration are thus rendered more forcible, and the expulsion of mucus from the cavity of the lungs necessarily accomplished. ”

“ The thoracic duct has a length of from sixteen to eighteen inches, and is about as large around as a goose quill. The lower end terminates in an enlargement in the abdominal cavity, called the receptacle of the chyle. It is provided with valves throughout its course, in addition to one of considerable size which guards the opening into the blood vessel. ”

“ S21.451 Open bite of right back wall of thorax with penetration into thoracic cavity S21.452 Open bite of left back wall of thorax with penetration into thoracic cavity S21.459 Open bite of unspecified back wall of thorax with penetration into thoracic cavity S21.9 Open wound of unspecified part of thorax Open wound of thoracic wall NOS S21. ”

“ If the thorax be pierced from any point whatever, provided the instrument be directed towards a common centre, A, Plate 1, the lung will suffer lesion; for the heart is, almost completely, in the healthy living body, enveloped in the lungs. So true is it that all the costal region (the asternal as well as the sternal) is a pulmonary enclosure, that any instrument which pierces intercostal space must wound the lung.
As the sternal ribs degenerate into the “false” asternal or incomplete ribs from before, obliquely backward down to the last dorsal vertebra, so the thoracic space takes form. ”

“ It will be observed that when the sides are spread apart air flows into the bellows. When they are pressed together the air flows out. If an air-tight sack were hung in the bellows with its mouth attached to the projecting tube, the arrangement would resemble closely the general plan of the breathing organs (Fig. 41) . One respect, however, in which the bellows differs from the thorax should be noted. The thorax is never sufficiently compressed to drive out all the air. Air is always present in the lungs. This keeps them more or less distended and pressed against the thoracic walls. ”

“ In all cases of double pleurisy, where the total amount is sufficient to fill one whole cavity, we ought not to postpone operating. Even when the effusion is not very large, if there are other diseases of the respiratory or circulatory systems to cause grave complications, and danger of increased impairment of their functions, thoracentesis is rendered necessary. That these conditions justify thoracentesis we believe no one who has any practical experience will question. ”

“ Its hemostatic power is also observed in bone cavities. Care should be taken never to use it unless there is a free [Pg 25] exit, as it increases rapidly in volume after coming in contact with dead tissue or pus, and serious accidents have happened from its improper use; for instance, if it is injected into an abdominal sinus where free escape is not provided for, the distention will result in ruptures of the sinus and infiltration of the surrounding tissues; possibly of the peritoneal cavity. ”

“ If the air enters the pleura and takes the place of the pus, the chest remains enlarged. Indeed, it sometimes increases in size to such an extent as to cause suffocation unless the pus and gas are withdrawn. The valve made by the false membrane allowing the air to enter the cavity, but not to escape from it, causes the fluid to accumulate rapidly, and we have pneumothorax to a very painful degree. The diaphragm is pushed down, and, if the disease is on the right side, the liver is forced down, and descends to a level with the umbilicus. ”

“ Though the lungs are closely applied to the costal sides at all times in the healthy state of these organs, still they slide freely within the thorax during the respiratory motions—forwards and backwards—over the serous pericardium, E, and upwards and downwards along the pleura costalis. The length of the adhesions which supervene upon pleuritis gives evidence of the extent of these motions. When the lung becomes in part solidified and impervious to the inspired air, the motions of the thoracic parietes opposite to the part are impeded. ”

“ It is irrefutable that the variations in the circumference of the thorax (and, of course, in its diameters) are so considerable that no certain normal mean for a thorax that has breathed, and for one that has not breathed, can be laid down. In most cases the measurements of the thorax are incapable of determining whether the lungs contain air or not. The reasons for these variations is, without doubt, to be referred to the congenital differences in the volume of the osseous thorax; partly, also, to the thickness of the soft parts, particularly of the subcutaneous fat and the thoracic muscles ”

“ The two lungs must, therefore, be alternately affected as to their capacity according as the heart occupies space on either side of the thorax. In expiration, the heart, E, is more uncovered by the shelving edges of the lungs than in inspiration. In pneumothorax of either of the pleural sacs the air compresses the lung, pushes the heart from its normal position, and the space which the air occupies in the pleura yields a clear hollow sound on percussion, whilst, by the ear or stethoscope applied to a corresponding part of the thoracic walls, we discover the absence of the respiratory murmur. ”

“ If, as is sometimes the case, the difficulty proceeds from a relaxation of the diaphragm, with general sagging down of the thoracic and abdominal viscera, so as to draw upon the trachea, then treat the whole trunk tonically, using the B D current. Place the N. P. low on back of neck, and treat with P. P. over the abdomen and thorax, and especially all around the edge of the diaphragm—along the lower line of the false ribs. Treat with medium strength of current, ten minutes, three times a week. The aim is to contract all the relaxed parts, so to relieve the larynx from the strain upon it. ”

“ The lung itself has sometimes to be operated on, as when it is the seat of an hydatid cyst, or when it contains an abscess cavity which cannot otherwise be drained, or when it becomes necessary to remove a foreign body the exact situation of which has been revealed by the X-rays. Portions of some of the ribs having been resected, the pleural cavity is opened, and if the lung has not already become glued to the chest-wall by inflammatory adhesions, it is stitched up to the chest-wall, and in a few days, when adhesions have taken place, an incision is safely made into the lung-tissue. ”

“ The above operation may be performed before closing the wound in the abdomen or replacing the intestine into the cavity, as it will then leave more room to collect the fluid which may escape from the lungs.
The lungs should in all cases be well injected, either through the trachea or by the process given above. The air passages must be carefully stopped with cotton. The mouth being closed, the nostrils are about the only air passages which require the attention of the operator. The eyes, after a few days, are liable to sink in the sockets, which gives the body an unnatural appearance. ”

“ The study of their development shows that they grow into the tissue as a closed system of minute tubes, which indicates that in all probability they remain permanently closed. If we trace the lymphatic vessels towards the thorax we find that in some part of their course they terminate in structures known as lymphatic glands. From these again fresh lymphatic vessels arise which carry the fluid towards the main lymph-vessel, the thoracic duct. This runs up the posterior wall of the thorax close to the aorta, and finally opens into the junction of the internal jugular and left subclavian veins. ”

“ Expectoration continued the same, of tough, ropy mucus, small in quantity, and got up with difficulty from the air-passages. In repeated examinations with the stethoscope, there was considerable dulness over the whole thoracic region, no bruit whatever could be discovered in the left side of the chest, no cavernous indication, although that side of the thorax was fully developed. The mucous râle was heard very strong in the upper lobe of the right lung, and some little crepitation at the inferior angle of the scapula on the same side. ”

“ Now if we examine in a dog the thoracic duct during digestion, which can easily be done by opening quickly the thorax on the right side, raising the lungs of that side, and by cutting the pleura along the aorta, which allows you to see immediately this canal then very white on account of the chyle that is passing through it, if, I say, we examine the thoracic duct in action, we shall see that the circulation goes on there nearly as in the veins. By opening it then, a more powerful throw of fluid does not indicate a greater velocity than that of the venous blood. ”

“ Ligature of the aorta may result in either an increased or decreased flow of direct lymph. One explanation of these results has been offered from a study of the changes in capillary pressure set up in the main organs involved. Thus, after ligature of the portal vein the capillary pressure in the intestines rises, and it was proved that the increase in thoracic duct lymph came from the intestines. Ligaturing the inferior vena cava causes a big rise in the pressure in the liver capillaries, the intestinal capillary pressure remaining practically unaltered. ”

“ Cancer of the lung or pleura may, by pressure, produce absorption and destruction of the walls of the blood-vessels, and cause discharge of their contents into the pleural cavity. Sir Thomas Watson253 reports a case where enormous hæmothorax caused enlargement of the left side, pushing the heart to the right of the sternum from caries of two ribs with ulceration through an intercostal artery. The blood never escapes from the lung into the pleura when there is considerable pulmonary apoplexy. ”

“ The consequences of the obstruction to the lymphatic and pulmonary-artery circulation may be very serious. In grave cases the lung breaks down, forming a gangrenous-like cavity, which differs from an ordinary cavity in not being rounded; it is more like a gangrene or slough. In a few cases the pathological appearances indicate phthisis, chiefly interstitial, with formation of cavities; sometimes traces of cavities are found which have cicatrized. More commonly oedema is developed in the lung and the bronchial passages. ”