Elements of Surgery

by Robert Liston

Above all, disuse and a proper position of the affected part must not be neglected. Unless absolute repose is strictly enjoined and attended to, and the return of blood from the inflamed tissues is favoured, very great difficulty will, in the majority of cases, be experienced in removing any of the signs or symptoms of inflammatory action, even by the most energetic means, general or local. This will be more fully insisted upon in the progress of the work.

OF SUPPURATION AS A CONSEQUENCE OF INFLAMMATORY ACTION.

It has already been stated, that the blood is stagnated in the capillaries occupying the centre of the inflamed part, as well as extravasated in the contiguous cellular tissue. Pus has long been considered as a secretion; but, from the time of Mr. Hunter downwards, a great similarity between the globules of pus and those of blood has been recognised: the former, however, are spherical, larger, and rougher on the surface, and are not so regular in size as those of blood; their diameter is between 1/2000 and 1/3000 of an inch, although some of the globules may be occasionally seen a little larger or smaller than these measurements. Smaller particles are also detected, the molecules of the pus globules, each of which contains two or three. These molecules are insoluble in acids, soluble in caustic

alkalis, and can be freed from the fibrous capsule in which they are contained, and of which the pus globule is composed, when treated with acetic acid. The appearance of the pus globules and molecules is here shown upon a scale, the squares of which are 1/4000 of an inch. These small particles were pointed out to me by my friend, Mr. Gulliver, nearly two years ago, as constituting an important element in suppuration. It results from his observations that the entire pus globule is composed in its central part of these minute molecules, the diameter of which is from 1/10666 to 1/8000 of an inch, cemented together, as it were, by a superficial deposit of matter possessing all the properties of coagulated lymph. And these minute nuclei constitute a proximate animal principle, possessing such well marked characters as to justify us in regarding them as peculiar in their nature, and essential to the composition of the pus globule. Thus they resist putrefaction with remarkable pertinacity, are very dense, and spherical in form, and are insoluble in some acids which act with facility on albumen, fibrin, or the blood-corpuscle. They are easily seen by treating a little recent pus with sulphurous acid, which so acts on the pus-globule as to render the nuclei distinctly visible through its fibrinous capsule; by sulphuric acid the external part of the pus-globule is quickly dissolved, and the nuclei, somewhat shrunk, are seen in considerable numbers floating separately about the field of vision. The instrument used by Mr. Gulliver in these observations was a compound achromatic microscope, with a deep object glass, having one-eighth of an inch focal length.

In many constitutions, the slightest incited action of the vessels is followed by the formation of pus, and the appearance of a depôt of purulent matter is often the first indication that such action has existed; but in the majority of instances, the deposition of pus is preceded by the usual characters of well-marked inflammatory action. Suppuration occasionally occurs without previous solution of continuity; for pus is frequently contained in the serous and mucous cavities, when no breach of continuity can be discovered, at least we find a fluid not distinguishable from purulent matter; it may be a vitiated secretion, but still it presents the usual characters of pus. But it occurs, generally, when there has been a previous læsion of structure, and in this case its progress is most distinctly marked. In exposed cellular texture, for example, particles of blood are effused; the serum is afterwards absorbed, and the lymph remains; this latter gives transmission to minute vessels which deposit the purulent fluid, whilst others secrete particles of organised matter to form granulations, in order to repair the loss of substance. This process is often unattended with any great degree of constitutional disturbance, because the fibrin effused sets a bound to the pus, and is the provision against its being mixed in large quantities with the blood. In healthy suppuration, the separation of fibrin and pus from the blood in this way seems to have direct relation to each other; and in unhealthy inflammation, when this does not take place, the consequences are mixture of pus with the blood as formerly noticed. In the latter form of suppuration the fibrin, instead of being assimilated to the contiguous mass, is mixed with the pus; hence the proneness to putrefaction of such discharge, and its disposition to coagulate spontaneously when evacuated. This kind of suppuration, being matured generally without thickening of parts, has been sometimes pointed out as suppuration independently of previous inflammatory action.

After purulent matter has begun to accumulate under the surface, the pressure thereby occasioned produces condensation of the neighbouring cellular tissue, which, along with the previously effused lymph, forms the parietes of the abscess; and in proportion as the matter accumulates, the cavity enlarges by the successive processes of ulceration of portions of its parietes, by continued effusion of lymph, and by farther condensation of the surrounding parts. Thinning of the parietes takes place by ulcerative absorption, particularly towards the surface—or, if that be difficult, towards a mucous outlet—as is exemplified by the bursting into the bowels or bronchiæ of abscess of the liver.

But in some instances, when no lymph is previously effused, and no cyst is formed, the matter is not confined, but pervades the cellular substance extensively, and is generally followed by more or less sloughing of that tissue, and by great constitutional disturbance. This most frequently occurs in patients of a debilitated habit, in whom the incited action has been so slight as not to cause the effusion of lymph, by which nature usually sets bounds to the suppurating process.

M. Gendrin advanced the opinion that pus was nothing but transformed blood; but his experiments on frogs are at least doubtful, since Mr. Gulliver, on repeating them, could not by any means induce the process of suppuration in these animals. It has been rendered probable by this gentleman’s observations that suppuration is a sort of proximate analysis of the blood, the fibrin being added to the contiguous parts, as in causing them to swell, forming the cysts of abscesses; the blood globules altered into pus being discharged as useless and excrementitious matter.

Pure pus is heavier than water, of a yellowish-white colour, somewhat of the consistence of cream. It is very little inclined to putrefaction, less so, perhaps, than any animal fluid not oily. It is composed of globules, and a clear transparent fluid, coagulable, it has been said, by the muriate of ammonia. When a solution of this salt produces any change, it is by rendering the pus more ropy; not coagulation, but a sort of gelatinisation follows. It is said also to be sweet and “mawkish to the taste.”