Hydrothorax

“ Disconnected from such complications hydrothorax will often give way to an active treatment similar to that indicated above. In some cases however our only hope of even temporarily prolonging life lies in the operation for drawing off the fluid.
Tapping the chest or as it is technically called thoracentesis or paracentesis thoracis has proved sufficiently successful in the lower animals to warrant its continuance in cases that resist other modes of treatment. ”

“ The principal cause of collapse involving an entire lobe or the whole lung is the presence of liquid in the thorax in the form either of inflammatory serous effusion, empyema, or hydrothorax. The admission of air into the cavity of the chest by perforation of the lung or by a penetrating wound of the thorax may also lead to the same result by allowing atmospheric pressure on the lung. In such cases the lung may again expand on the absorption or withdrawal of the liquid or air, but it sometimes remains permanently compressed and carnified. ”

“ PATHOLOGICAL ANATOMY.—Hydrothorax being merely dropsy of the thoracic cavity, there is no lesion of the pleura. There is a collection varying from 100 grammes to many liters of fluid in the cavity. It differs from the effusion in subacute pleurisy in its small quantity of fibrin, in having far less of albuminoid material, and no white blood-corpuscles. The water collects almost always in both sides of the chest, more on the side on which the patient lies in bed. In the recumbent position the fluid gravitates posteriorly more than the effusions of pleurisy. ”

“ William Hamilton, the author of a valuable treatise on the digitalis purpurea, thinks the hydrothorax a more frequent disease than has commonly been imagined, because he conceives that it has often been mistaken for organic disease of the heart. He names, with some precision, many symptoms of the latter complaint; but how remote he is from an accurate knowledge of it may be discovered by his opinion, that, in diseases of the heart, “the patient can lie down with ease, and seldom experiences much difficulty of breathing.” ”

“ The exercise of walking slowly, in pleasant weather, although it increases the palpitations at the moment, is followed with relief from the distressing feelings, which are increased when she sits still for a long time. She has no suspicion of her hopeless situation, and confidently expects relief from medicine, yet labours under a melancholy which is unnatural to her.
CASE OF HYDROTHORAX.
The following case of hydrothorax will shew, that water may exist in the chest without the symptoms, which we have attributed to organic diseases of the heart. ”

“ Unlike what occurs in hydrothorax and hydrocephalus, the effusion in the present form of dropsy is of inconsiderable importance, compared to the visceral disease which is its remote cause. When, however, the accumulation becomes very considerable, the pressure of the fluid may affect the organs, and more particularly the peritoneal lining, which from the irritation induced in it, may take on a higher grade of inflammation, terminating in effusion of coagulable lymph or pus, and in death. ”

“ Auscultation.—The presence of fluid between the lung and parietes prevents us from hearing the vesicular murmur. The distant bronchial respiration is rarely heard in hydrothorax, as it is in pleurisy, because the lungs are not completely deprived of air, and when present is less intense. Ægophony is frequently heard over the upper limit of the fluid, the whispering voice being transmitted through the fluid. Owing to pulmonary oedema there are subcrepitant râles, but never pleuritical friction sounds. ”

“ Treatment, diuretic, tonic, derivative, thoracentesis, trochar and cannula or aspiration, point of election for puncture, method, asepsis, drainage by aspirator, or into an antiseptic solution, eligible cases, dangers attending thoracentesis, shock, rupture of false membranes and lung, infection of pleura, injection of antiseptics.
Hydrothorax or water in the chest is common to all domestic animals. It is as we have seen one of the most ordinary results of pleurisy, and may persist long after that disease has disappeared. ”

“ Exercise accelerates the rate of respiration and intensifies this sound. The vesicular murmur is heard only where the lung contains air and its function is active. The vesicular murmur is weakened as inflammatory infiltration takes place and when the lungs are compressed by fluids in the thoracic cavity, and disappears when the lung becomes solidified in pneumonia or the chest cavity filled with fluid as in hydrothorax. ”

“ General principles only can be inculcated and their adaptation to the varied phases of different cases left to the judgment of the student.
259 HYDROTHORAX. All animals liable. Causes, pleurisy, obstruction to pulmonary or intercostal veins, heart disease, Bright’s disease, anæmia, parasitic or otherwise. Effusion reddish gray or clear straw color, inflammatory and dropsical. Symptoms, troubles of respiration, as a secondary disease complicated by dropsies elsewhere, signs of hydrothorax without fever, shedding of hair. ”

“ Occasionally cases are met with in which the œdema is peculiarly localized and fugitive. If attention is directed to the heart, a bruit and other evidences of dilatation of the organ and of arterial relaxation, just as in the first case, are discovered. If the lungs be examined, one may or may not discover signs of single or double hydrothorax, although, probably, not to a very great extent. The lungs themselves are healthy. On getting him out of bed it is found that the patient can hardly walk ”

“ Lymph-channels are frequently obstructed, but no appreciable diffused retention of lymph results unless the thoracic duct is obstructed. This rare affection is followed by enormous distension of the thoracic and abdominal portions of the parts beyond the stenosis. Ascites and hydrothorax may follow, but not necessarily any considerable oedema of the peripheral parts of the body. As a result of the distension of the thoracic duct, rupture is not unlikely to take place, and the effused fluid contains chyle.26 ”

“ In the course of the disease, dropsical effusions, constituting Ascites, Hydrothorax and Anasarca, are not [Pg 31] unusual, as in other diseases where great debility is produced.
In the advanced periods of Consumption, diarrhœa constitutes a prominent and troublesome symptom. This is sometimes produced by any cause which checks the profuse sweats; while on the other hand, if the diarrhœa be checked, the cough and dyspnœa, which perhaps had been relieved by it, frequently return with redoubled violence. Under these circumstances, the condition of the patient is hopeless indeed. ”

“ Digitalis is often valuable in improving the heart’s action, and acting freely on the kidneys. Dry capping on the chest acts as a derivative.
206 ATELECTASIS. COLLAPSE OF LUNG. Atelectasis in bronchitis, congenital, etc. Airless condition in the absence of exudation. Causes, congenital persistence in butcher animals. Blocking of air tubes by exudate—ball valve. Desquamation of ciliated epithelium. Compression by hydrothorax, pneumothorax, and false membrane. Symptoms. Percussion flatness, juvenile respiration elsewhere, blowing sounds loud. Drum-like sounds on emphysema and pneumothorax. ”

“ 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. ”

“ 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. ”

“ The lungs are freely suspended by the windpipe, and are distended by the atmospheric pressure in opposition to their elasticity. Consequently, an opening in the walls of the thorax is liable to produce suffocation, by giving the air a more direct and easy route to the vacuum of the chest than through the trachea and lungs.
A delicate membrane called the pleura closely invests the lungs, and is then reflected to line the cavity of the thorax. By the secretion of a serous fluid, it prevents friction, which would otherwise result from the constant movement. ”

“ 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. ”

“ PATHOLOGICAL ANATOMY.—In traumatic pneumothorax and simple cases, such as from the bursting of emphysematous alveoli, the presence of air is the only pathological product. If the pleura and adjoining organs are not diseased, the rupture or tearing cicatrizes rapidly, and the air disappears in a few days by absorption. If a quantity of air be admitted, the pneumothorax may last for months; yet if the pleura is healthy, the air itself will not produce local changes. If blood or morbid products flow in with the air, then inflammatory changes occur, and we have deleterious products effused. ”

“ 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. ”

“ 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. ”

“ The symptoms, prognosis, and treatment vary accordingly. Through a patent orifice the air enters in inspiration, and goes out with the expired air from the lungs. As it cannot accumulate, there can be no positive air-pressure within the pleura. If, however, the orifice be valvular, although the air enters it does not escape, for it presses upon the valve and closes it. If the valvular fold be perfect, the air soon becomes excessive in quantity, and exerts dangerous pressure upon the lung and adjacent organs. ”

“ Pneumothorax is the only pathologic condition associated with signs similar to those of expiratory, valve-like bronchial obstruction by a foreign body.
3. Partial bronchial obstruction by an object such as a nail allows air to pass to and fro with some degree of retardation, and impairs the drainage of the subjacent lung. Limitation of expansion will be found on the invaded side. The area below the foreign body will give an impaired percussion note. Breath-sounds are diminished in the area of dullness, and vocal resonance and fremitus are impaired. Rales are of great diagnostic import ”

“ The lung must lose in size by its retractile force, and when that is overcome the fluid must press in all directions. The fluid gradually rises from the surface of the pleura over the diaphragm, and the lung, by negative pressure, draws it and the fluid upward. As long as the diaphragm is arched, although the lung recedes before the effusion, it is not really compressed. When, however, the diaphragm yields and falls from the large quantity of fluid, then the fluid conquers the lung. ”

“ The backward pressure of the fluid upon the bronchi, trachea, aorta, and oesophagus interferes with their functions and actions. There may be bronchial or blowing respiration heard over the lung, due to compression of the parenchyma. The fluid around the heart prevents free motion of the organ, although not to so great an extent as in adherent pericardium; complete diastole does not occur; the auricles and ventricles are not completely filled; the systemic and pulmonary circulations become engorged, and pressure is exerted upon the coronary arteries, thus disturbing the nutrition of the heart. ”