As the accession of inflammation depends upon a change of the natural action of the vital principle, so does its removal depend upon the reconversion of this into the natural action, which implies activity, or an active state. If, then, we bleed in the end of inflammation, we lessen the powers of the part so much, as to prevent restoration; gangrene, therefore, will take place: Or, if the part be less delicate, and the progress of the action consequently slower, the inflammation may continue stationary for a considerable time, and become chronic, or habitual. This state is not to be cured by bleeding, but will rather be made worse by it. Whenever, then, after inflammation has continued for a length of time, we find, that venesection does not produce the usual abatement; or, whenever, although there be a temporary abatement, the pain increases afterwards to a greater degree, we may be certain our treatment is improper. We likewise find, that the longer bleeding has been delayed, in the beginning of the disease, the sooner must we stop, and the less quantity must we take at a time; because, in this case, the inflammatory action is nearer its termination, and is more ready to produce gangrene, if the parts be delicate, or the action great, or, if otherwise, the inflammatio assuefacta. We are also to refrain from bleeding, when we find that the inflammatory action is about to terminate in another action; as, for instance, the suppurative; because, in the first place, bleeding, in this new action, can do no good, but, by weakening, will do harm; and, secondly, if there be only a tendency to this action, the action not being yet formed, or beginning to form, we may, by bleeding, interrupt the progress of the inflammation, and convert it into a more tedious disease, or the inflammatio assuefacta.
Bleeding has been used, not only as a cure for inflammation, but also as a preventative; but this must be considered as proper, only in particular instances. When, for instance, an wound has been inflicted, or an operation necessarily performed, on a robust person, bleeding immediately, or very soon after it, may be useful; because it will tend to lessen the chance of the natural action being carried so high as to become changed. These people cannot have their action much increased without disease; and, therefore, it is necessary to lessen it, and bring it down to a more proper medium. But there are other cases, where the action is naturally rather too low, and the patient weakly. In these cases, bleeding can do no good, but much harm; because it increases the previous weakness, and makes the inflammation, if it does occur, more dangerous, on account of the little power which there is to support the action. These people even bear bleeding worse than others, when inflammation has actually taken place. It ought never to be practised, in order to reduce the natural action, before disease has taken place; and, after the inflammatory action is induced, it ought to be used cautiously, and only to such an extent, as may be necessary for removing the tendency to immediate bad consequences. It ought, however, to be used very early in the disease; because, in weak people, the action does more harm in a given time, than in the strong; but it ought likewise to be sooner abandoned, otherwise we either hasten mortification, or prevent the act of restoration from taking place.
Bleeding is rarely necessary in inflammation of the cellular substance alone, unless the action be extensive; in which case, the system is so affected, as to require our interference. When the cutis is inflamed, producing erysipelas, the system suffers considerably; but, as this frequently ends in mortification, bleeding has been neglected by many; but it is evident, that, if the disease be simple, and not dependent upon any specific agens dissimilis, or epidemic contagion, venesection is the proper cure, provided it be early employed, as we thus diminish the action more certainly than by any other means. If, however, the disease have been neglected, and the action be nearer a termination, then we must either do nothing in the way of general treatment, or must give opposite remedies from bleeding, according to circumstances. When muscles are inflamed, bleeding is often necessary to a very great extent, as we observe in rheumatism; and, in the beginning, we must take a greater quantity at a time, in order to procure an abatement, than in many other cases. When the viscera are inflamed, bleeding is uniformly necessary, and generally requires to be frequently repeated.
It is a common opinion, that the blood ought to be taken, if possible, from a vein which arises from, or near the affected part; that, for instance, in phrenites, we should bleed in the jugular vein; in inflammation of the feet, we should bleed in the leg, &c.: And, when this can conveniently be done, it may be preferred; because, it not only possesses all the advantages of general bleeding from any other vein, but also may be supposed to produce, in a slight degree, a topical evacuation. If, however, the veins be so small, that we cannot detract enough of blood, and sufficiently quickly; or if, from any other cause, we cannot do so, then, if the general action be violent, we must have recourse to another vein, as the loss to be sustained, by confining ourselves to this vein, is infinitely greater, than any good which can be derived from it, as a local evacuation. Indeed, when we consider the laws of the circulation, we must allow, that very little good can be done in this way, as a local detraction; because one vein does not lose more blood than another, except during the moment of the flow.
The blood, when drawn during inflammation, has always a buffy coat, which is, in general, thicker, and more concave, in proportion to the violence of the inflammatory action; and the continuance of this condition, is one circumstance which points out the necessity of continuing our evacuation: But the mere existence of a buffy crust, is not, without these circumstances, any infallible sign of the necessity of bleeding; because this crust is to be found on the blood, after the inflammation has begun to become passive; and it is to be found also, when mortification is approaching; we observe it likewise very frequently upon the last cup of blood which we find it necessary to take away. In these cases, however, the crust is much softer, generally thinner, always flat, instead of concave, and looser in the texture; it is also more of a greenish hue. These circumstances, conjoined with the state of the pulse, will enable us to judge, whether we should totally desist from, or continue our evacuations with caution. Most frequently they forbid farther bleeding.
Cold, or the subduction of heat, is chiefly useful as a topical application; but it is also proper to be applied, in moderation, for the abatement of the general fever, unless we be desirous of procuring perspiration. The quantity of bed-clothes ought to be lessened, cold drink should be allowed, and a free circulation of cool air into the room. The application of cold, however, ought, in general, only to be carried to such an extent as shall be sufficient for diminishing the morbid degree of heat, and not so far as to produce sensible cold, or the sensation of cold; because this, in many instances, will be pernicious, upon the principle of the sympathy of equilibrium, the action of the internal parts being increased by the speedy application of cold to the surface; and, therefore, if the internal parts be inflamed, their morbid action must be still farther increased. If the cold be long applied, to any considerable degree, it will likewise, by the sympathy of association, weaken the whole system too much, and injure the act of restoration. As bleeding is to be used only until it restores a natural state, and abates pain, so also is cold only to be applied in such a degree as may be necessary for diminishing the preternatural heat, and sensation of the surface; which it does, by lessening the morbidly increased action, and reducing it to the natural state. The degree must therefore gradually be diminished, in proportion as the general disease subsides, otherwise we injure the system, and prevent recovery. There is, however, this difference betwixt bleeding and the application of cold, that the first may be used suddenly, and to a considerable extent at once, whereas, the second ought, especially in all cases of internal inflammation, to be employed more slowly, and its degree regulated by the degree of the general heat of the surface.
Nauseating medicines are also very useful, independently of the sweating which they frequently induce; and are a very powerful mean of abating action in general[5]. Employed, after bleeding has been used once or twice, they are productive of considerable benefit; but there are some affections, in which they cannot be used, such as inflammation of the stomach and intestines; but in inflammation of the lungs, of the throat, muscles, or surface, they may often be prescribed with benefit. The remedies usually employed for this purpose, are, small doses of emetics, given without drink. It must, however, be remembered, that these frequently produce considerable evacuations, either from the skin or bowels, and, therefore, may occasion a permanent weakness. We must likewise avoid raising the sickness to a great degree, and keeping it long up; because the same objection applies nearly to this as to bleeding ad deliquium.
Purging is frequently employed in the cure of inflammation, especially such purgatives as are called cooling, which, in this case, is an imaginary quality; but, unless in so far as they tend to abate the irritation of costiveness, they can do no more than bleeding can, and are, in many respects, inferior to it. They are, in one view, to be compared with the application of cold, which is only indicated when there is much heat; both are intended to diminish action, chiefly by removing stimuli from the part to which they are applied. Purging is very uncertain in the effects which it produces on the system, and in the degree of weakness which it causes; and, therefore, never can be put in competition with bleeding, as a general remedy; and, wherever bleeding is improper, or its propriety doubtful, purgatives are still more injurious. They operate likewise so slowly, at least comparatively speaking, that they do not influence the local action so much, as the loss of such a quantity of blood, as would produce an equal effect on the body, will do, unless in particular cases, when they act upon the principle of the sympathy of equilibrium; as, for instance, in pulmonic inflammation, when they sometimes are of service, by increasing the action of the intestines, and diminishing that of the lungs[6]. In the same way, emetics sometimes cure slight inflammation of the tonsils. One of the best and pleasantest saline purgatives, is the phosphate of soda, which may be given to an adult in the dose of an ounce, in order to obviate the effects of costiveness. If we wish to use it, upon the principle of the sympathy of equilibrium, we must give two ounces, or more. The same cautions which were given, with regard to bleeding, apply also to purging.
Sweating, considered as a mean of abating general action, is, in most cases, inferior to bleeding; and can never, when the general inflammatory action is considerable, be trusted to alone; but, after the use of the lancet, it is generally serviceable. It is useful, in particular, when the local disease is not confined to a small spot, but affects a considerable surface, or different parts of the body; as, for instance, in the rheumatism; but it acts, in these cases, rather by the sympathy of equilibrium, than by any other mode. At the same time, the induction of a sweat, preceded by bleeding, (which tends to abate the local action as well as the general one) will sometimes be useful, by giving a secretory termination to the general disease, and hastening its conclusion. In the first point of view, sweating may be used early in the disease, especially if preceded by bleeding. In the second, it will be chiefly useful toward the end, as it will then accelerate the termination, and thus influence the local action; for the abatement of the general action must also produce an abatement of the action of a particular part. Sweating, as well as purging, must be used with caution in weakly people, or in those who are reduced by disease; because, although the action of particular parts may be increased by it, yet, partly in consequence of this temporary increase, and partly on account of the fluid which is discharged, general weakness is induced. One of the best sudorifics is the pulvis ipecacuanhæ comp.; of which we may give ten grains every hour, until sweating be produced, giving warm lemonade alongst with it. The tartar emetic is also a very useful sudorific; the sixth part of a grain may be given every half hour, until the proper effect be produced[7].
Some of the agentes dissimiles may be considered as proper remedies in this complaint; such as, digitalis, laurel water, lead, &c.; But they are certainly inferior to blood-letting; and have been so little employed in this way, that their effects are not ascertained[8].