Elements of Surgery. Robert Liston

This may occur with or without rupture of the vessels, and to a greater or less extent, according to the violence of the action, and the texture of the part.

      When local inflammatory action exists to a considerable degree, the general circulation is more or less disturbed. The heart, and the larger vessels supplying the capillaries, which are more immediately concerned in the local action, subsequently sympathise with the part affected, and, acting with greater vigour than usual, propel the blood into the extreme branches; so that the inflammatory excitement may be said to be gradually communicated by the continuous sympathy, till the whole sanguiferous system becomes subject to its influence. The degree of this general excitement depends greatly on the texture and function of the part primarily affected.

      The term Passive Inflammation has been applied to that state in which the larger vessels are not excited, or have ceased to sympathise with the capillary branches. The term Chronic Inflammation is properly limited to the consequence of the acute inflammatory action, the part remaining turgid and swollen, the vessels over-distended with dark blood, but with little or no pain, and without heat or throbbing. Congestion is also employed to denote fulness of the vessels, large as well as small, when no sign of excited circulation, or of decided inflammatory action, has occurred. It is most frequently used, however, when describing the condition of an internal organ. An over-distention of a particular set of vessels may certainly exist (as a consequence of inflammation, or altogether unconnected with it), unattended with inflammatory action. These two states ought to be carefully distinguished from a similar condition of the vessels, attended with inflammation; for practice, which would be beneficial in the one case, is highly prejudicial in the other, and lamentable examples of the non-attention to this distinction are every day observed.

      It may here be mentioned, that some have denied the existence of vitality in the blood; and to some minds it may, perhaps, be difficult to conceive how a fluid should be possessed of this principle. But no one can either doubt or deny that the blood, in its distribution, in its manner of receiving increase, in the secretions furnished by it, and in its various morbid changes, is governed by certain laws and principles which cannot be explained by those of chemistry or mechanics, but must belong to some other power. It is allowed, and has been promulgated by all authors, that the blood is one of the most active agents in the animal economy—in repairing waste, in affording peculiar fluids necessary in that economy, in supplying organs with materials for carrying on their functions, &c.; and yet all this, according to some, is accomplished by a dead animal fluid; no one can plausibly object to the laws by which the blood is governed being referred to the power of life, and to their being called Vital Principles.

      Certain circumstances give rise to inflammation, and have been called its Exciting or Immediate Causes. Among the external applications producing inflammation, stimulants bear a conspicuous part; the effects of which, in causing this action, are well shown by many experiments that have been performed on the lower animals: by the application of ammonia, spirits of wine, or common salt, for example, to the diaphanous web of a frog’s foot. As stimulants usually causing inflammatory action, by their being applied to the surface of the body, may be enumerated acids, alkalies, certain salts, animal substances, such as cantharides, the juices of many plants, many poisons, an excessive degree of heat, &c. Any solid substance, though by no means acrimonious in its quality, may act as an exciting cause, as by pressure or friction.

      Wounds also, especially when of considerable size, and occurring whilst the constitution is in an unhealthy condition, give rise to local, and occasionally general, inflammatory action.

      This action is besides frequently produced by injury from an obtuse body causing a bruise or fracture; by the lodgement of extraneous substances, or of decayed portions of the system,—such as portions of bones, tendons, &c.; or by irritating matter generated in the system itself,—by concretions, tumours, vitiated secretions, &c.

      One of the most frequent causes of inflammation is cold; the action of which, however, cannot always be readily explained. In some instances, it appears to act directly on a part, as in inflammation of the mucous membrane lining the organs of respiration: in others, its action is indirect, probably by disturbing the equality of the circulation, the inflammation occurs in a part distant from the surface the temperature of which had been diminished. In the great majority of instances in which inflammation has occurred, in consequence of very intense cold, it is produced by the sudden application of heat whilst the temperature of the part is greatly below the natural standard, as will afterwards be more particularly illustrated. But the inflammatory action may be produced, even though no heat be afterwards applied directly to the part, by its vessels being too rapidly brought into a degree of action similar to that of the surrounding parts which are in their natural condition. Sudden and general diminution of temperature seems to act as an exciting cause, by producing an instantaneous suppression of the transpiration. Another exciting cause of the inflammation, is the retention of the secreted fluids, causing unnatural distension of canals or cavities, and is exemplified by cystitis occurring in consequence of retention of urine. Certain states of the constitution are justly supposed to excite inflammation, in particular textures. Other exciting causes of inflammation might be enumerated, but these will be more naturally explained, and more fully considered, whilst treating of inflammation of the various tissues and organs. Their effects are various and diversified, according to the intensity of the cause, the structure, function, and sympathies of the part affected, and the state of the system. And it is also to be remembered, that not unfrequently inflammatory action appears, whilst we can assign no cause for its production.

      Inflammation is said to terminate in Resolution, Suppuration, and Mortification. The application of the word termination, however, is injudicious; for in general the inflammatory action, though much abated, is not extinguished by the occurrence of suppuration or mortification, but often continues in the surrounding parts with unabated intensity; and not unfrequently several of the terminations occur combined with each other.

      Adhesion has also been mentioned as a termination of inflammation, but perhaps improperly; for, although in certain parts of the body, as in the serous cavities, adhesion is produced in consequence of inflammatory action, and during its progress, still the process of adhesion is altogether independent of this action in other textures, such as the cellular. In the uniting of a flesh wound, a certain degree of incited action of the blood vessels is necessary for the accomplishment of the adhesive process; but should that incited action reach the inflammatory pitch, the union by the first intention is interrupted, and the wound must heal by granulation with suppuration. The process of adhesion will be more properly attended to when treating of wounds.

      The various terminations of inflammation are salutary or destructive, according to circumstances; but resolution is, in general, the one most to be desired; complete resolution, however, perhaps seldom occurs; after the inflammatory action has attained a certain point, this cannot be expected to happen.

      Resolution takes place in consequence of the reëstablishment of the circulation in the capillaries, in which the blood had stagnated; hence the diminution of the increased action in the larger vessels—the effused fibrin, at the same time, if there was much swelling, is partly absorbed. The circulation in the part becomes again natural, and the circulating fluid also resuming its healthy properties, the redness and sensation of throbbing cease. In consequence of the bloodvessels regaining their contractility, the nervous system is no longer preternaturally stimulated, and thus the increased sensibility is done away with. In short, when inflammation terminates in resolution, the part is left in the same state in which it was previous to the supervention of the attack. It is not an instantaneous process, but gradual in its completion.

      Again, it not unfrequently happens, when inflammation has occurred in the surface, and continued for a short period, that it spontaneously disappears, and does not again return; the action is said to terminate in Delitescence, and of course this is always a favourable occurrence. But if the inflammation, after having suddenly disappeared, attacks another part at a distance from that first affected, the change is termed Metastasis. If the inflammation leaves an internal viscus, and appears on the surface of the body, the circumstance is favourable; but if it leaves the latter to attack the former, the result is highly dangerous.

      Treatment.—In