8S9 



EMPYEMA. 



EMULSION. 



870 



as pure dogmatism ; for, how can we judge by analogy, if we do not 

 assume gome general laws to which the particulars are subjected ? 



If the empirics had remained true to their principles, their name 

 would stand high among the medical profession. But having aban- 

 doned the study of nature, and with it all scientific pursuits, they 

 sank into such disrepute, that their name became a stigma. And 

 even in our days when the natural sciences have, by the impulse given 

 by Lord Bacon to genuine experiment, risen to a high degree of per- 

 fection, and empiricism is the character of modern science and philo- 

 sophy, the name of empiric is still bestowed as an opprobrious term 

 upon all ignorant pretenders in the medical art. 



(Curt Sprengel, Getchichte der Medizin.) 



KMPYE'MA (ifanhiiui, from iv, ' in,' and tvov, ' pus,' a. word which 

 signifies an internal collection of pus). Although this term was 

 restricted by the ancients to purulent collections in the thorax, it is 

 now employed to signify all collections in the pleura which do not 

 arise from an obstruction to the circulating system, and are not of a 

 gaseous nature. In a natural state the pleura, like other serous mem- 

 branes, secretes a clear fluid, which is removed by absorption as 

 quickly as it is formed. But from the existence of inflammation or 

 the presence of foreign bodies, other fluids often accumulate. The most 

 common of these are serum, blood, pus, and fibrinous matter. Any of 

 them may be present alone, or may be mixed in varying proportions. 

 It is, however, almost impossible to ascertain by any external means 

 the nature of the fluid which has accumulated. Dr. Townsend relates 

 two cases of empyema : in the one, a cage of two months' standing, 

 produced by the bursting of a tubercular abscess in the lungs ; on the 

 fluid being removed, it presented all the characters of pug ; in another 

 cage, arising from the same cause, a perfectly transparent and colour- 

 less fluid was found. It is therefore not only difficult to discover the 

 nature of the fluid, but the same exciting cause may give rise to the 

 presence of different kinds of fluid. 



Whatever may be the nature of the fluid in the lungs, it always 

 exists in conjunction with a peculiar state of the pleura. This mem- 

 brane is covered over to a greater or less extent with a fibrinous 

 secretion, which, in this and other cases becoming organised, con- 

 stitutes what are known by the name of false membranes. This 

 fibrinous matter Is sometimes deposited in so large quantities on the 

 pleura, which covers the lungs, that even after the fluid is removed, 

 the lungs, which have been compressed, cannot expand, and con- 

 sequently the parietes of the chest fall in and occupy the vacant 

 space, and contraction of the chest is produced. The false membranes 

 thus produced are liable to various diseases, and they may inflame, 

 ulcerate, or become ossified, and thus produce various secondary 

 diseases. Sometimes the false membranes extend from one side of the 

 cavity of the pleura to the other, and a cage is related by Dr. Townsend 

 of a person " in whom the effusion wag divided by these partitions into 

 three compartments, so perfectly distinct from each other, that had the 

 operation of paracentesis been performed during life, that compartment 

 only could have been evacuated into which the incision had been 

 made ; so that in order to draw off the entire effusion it would have 

 been necessary to perform three several operationg." 



The worst effect of the presence of fluid in the pleura is exerted on 

 the lung. By its pressure the lung becomes incapable of expanding 

 for the admission of air. Its position is generally by the side of the 

 spinal column, but through the deposition of the fibrinous matter the 

 pleura of the lungs and of the ribs often contract adhesions, and in this 

 manner the lungs may be forced to occupy very varied positions in the 

 cavity of the thorax. When the effusion is extensive the lung becomes 

 flattened and flaccid, it* surface is corrugated, and its tissue becomes 

 soft, pliant, and dense, exhibits no crepitation, and is almost entirely 

 deprived of blood. It does not often inflame in this state, but fre- 

 quently becomes the seat of the deposition of tuberculous matter. 



Empyema is always attended with inflammation acute or chronic of 

 the pleura [PLEt'BiTis], although the bursting of an abscess or the 

 wounding of a blood-vessel may assist in producing the accumulated 

 fluid contents of the pleura ; at the same time it frequently happens 

 that the inflammatory symptoms are of so mild and insidious a nature 

 that they are entirely overlooked. This was more frequently the case 

 previous to the use of percussion and auscultation than at the pregent 

 day. It is in fact impossible by general symptoms alone to infer the 

 presence of empyema. The following symptoms however, taken with 

 the physical irigns, may be regarded as characterigtic : Difficult res- 

 piration, increased by motion, exertion and lying on the sound side ; f ul- 

 neas and oppression at the chest ; enlargement of the diseased side ; 

 protrusion of the intercostal spaces, with an obscure gense of fluctuation 

 and oedema of the integuments ; dulness of sound on percussion, and 

 absence of the respiratory murmur on the diseased side, which remains 

 perfectly motionless; noisy respiration in the opposite lung with 

 violent action of the respiratory muscles ; displacement of the heart ; 

 protrusion of the abdomen; a harassing short cough, small rapid 

 pulse, and the other symptoms of hectic fever. To these symptoms 

 some would add segophony, a sound on speaking like the bleating of a 

 goat, but this only occurs when there is a thin stratum of fluid in 

 the pleura, and it is absent when the empyema is extensive. The 

 intensity of all these symptoms is proportionate to the quantity of 

 fluid effused, the duration of the disease, and the constitutional 

 itrength of the patient. The difficulty of breathing is in proportion 



to the quantity of the fluid which presses on the lungs. The inability 

 to lie on the sound side arises from the pressure of the fluid upon the 

 sound lung when a person lies so that its weight comes directly upon 

 it. The cough is not a constant symptom, and may be entirely absent 

 where there is no inflammation of the lungs or bronchise. The hectic 

 symptoms will vary according to the strength of the individual and 

 the duration of the disease. Night-sweats do not occur in conjunction 

 with the other hectic symptoms in empyema, unless the lung is in a 

 state of tuberculous ulceration. 



There are few diseases with which empyema is likely to be con- 

 founded. Its general symptoms resemble those of tubercular phthisis, 

 but the history of the disease, and more particularly the stethoscopic 

 signs will point out the distinction. In phthisis there is no displace- 

 ment of the heart; absence of the respiratory murmur is usually 

 found at the upper part of the lung, and ia followed by mucous rale, 

 pectoriloquy, &c. Hepatisation of the lungs has been referred to as 

 likely to be confounded with empyema, but this is so rare a disease in 

 a chronic form, as to render it unnecessary to point out the distinction 

 between the two diseases here. The same remark applies also to 

 tumours in the sac of the pleura, which, although they have been 

 recorded, are too rare to need a description. Enlargement of the liver, 

 with that organ pressing upon the diaphragm and lungs, might 

 produce the same symptoms as in empyema, but a careful examina- 

 tion in connection with hepatic symptoms would soon indicate the 

 diagnosis. 



The treatment of empyema may be of two kinds, medical and sur- 

 gical. The general principles on which the first should be conducted 

 are those which would be applied in pleuritis. [PLEURITIS.] It, how- 

 ever, often happens that the resources of medicine fail, and that no 

 other chance of relief can be offered the patient than that of drawing 

 off the effused fluid by means of an operation. This is called the 

 operation of empyema, or paracentesis thoracis. This operation, 

 although in modern times it has got much into disrepute, was per- 

 formed by Hippocrates (Hipp., ' De Morbis,' lib. ii. 576 ; Galen, ' Com- 

 ment.,' Aph. 27) and the older practioners of surgery with apparently 

 much success. It has recently been recommended, especially by 

 Laennec, in cases of empyema which do not offer a chance of being 

 cured by medical treatment. In such cases, where all other remedial 

 means have been tried, there seems an increasing conviction that this 

 operation may be had recourse to with every chance of benefit : and 

 cases have now been recorded, both in the practice of the French and 

 English hospitals, in which a large proportion of those operated on 

 have recovered. Another class of cases in which paracentesis has been 

 recommended, are those in which the empyema is dependent on acute 

 inflammation of the pleura, and in which the fluid accumulates so 

 rapidly as to threaten suffocation unless removed. 



In the performance of paracentesis, the most eligible spot for the 

 operation is between " the fifth and sixth, or the sixth and seventh 

 true ribs, at the point just in front of the indigitations of the serratus 

 magnus, or midway the anterior and lateral parts of the chest." Some 

 surgeons however recommend that it should be done between the third 

 and fourth ribs on the left side, and the fourth and fifth on the right, as 

 they suppose there is danger of wounding the liver or diaphragm by 

 operating lower down. The integuments should be drawn on one side, 

 if it be intended that the wound should close after the operation, and 

 the incision through them should be about two and a half inches long. 

 The intercostal muscles will thus be exposed, and should then be 

 cautiously divided ; and when the pleura which lines the ribs is 

 exposed, a small puncture should be carefully made in it. In dividing 

 the intercostal muscles, the knife should be kept close to the upper 

 edge of the lower rib, in order to avoid the risk of wounding the inter- 

 costal artery, which runs in a groove upon the lower edge of the upper 

 rib. The size of the opening into the pleura must be regulated by the 

 nature of the effused matter. A cauula, supplied with a stopper, 

 should then be introduced and kept in the wound, so that the whole 

 or a part of the fluid may be drawn off. 



(Cifclopifdia of Practical Medicine, article ' Empyema ;' Cooper, 

 ikrtlimary of Surgery ; First Lines of Surgery.) 



EMPYREUMA denotes the peculiar and disagreeable smell and 

 taste resulting from the action of a considerable degree of heat upon 

 vegetable or animal substances in close vessels, whicli prevent such 

 an access of air as is required for perfect combustion : in this way 

 destructive distillation goes on so as frequently to produce an oil 

 which has a strong, burnt, or, as it is termed, empyreumatic smell and 

 taste. 



EMULSIC ACID. [FERMENT, EmMn.] 



EMUL8IN. [FERMENT.] 



EMULSION, a term applied to mixtures which generally have a 

 milky appearance, and which in some cases, are partial solutions, in 

 others merely mechanical suspensions of oily or resinous substances : 

 thus, the oil of the almond seed may be for a time diffused through 

 water by trituration, but will ultimately separate and float on the 

 surface. Many resins are formed into emulsions by means of the yolk 

 of an egg, or of gum-arabic ; while gum resins contain in themselves 

 the means of forming emulsions with water. Frequently syrups and 

 distilled waters are added to render the compound more palatable ; but 

 alcohol and acids should never be used. Emulsions should be used 

 soon after being formed, as in a few hours the constituent parts sepa- 



