Not only the cause just mentioned, but every other by which the eschar might be disturbed, must, therefore, be carefully avoided; and especially, as the eschar begins to separate from the healed edges of the sore, it should be carefully removed by a pair of scissors.
To the surface of the wound the eschar supplies a complete protection and defence, and allows the healing process to go on underneath uninterruptedly and undisturbed. It renders all applications, such as plasters, totally unnecessary, as well as the repeated dressings to which recourse is usually had in such cases; and it at once removes the soreness necessarily attendant on an ulcerated surface being exposed to the open air. In many cases too, in which the patients are usually rendered incapable of following their wonted avocations, this mode of treatment saves them from an inconvenience, which is, to some, of no trifling nature.
It has already been stated how important it is that the eschar should be preserved adherent. To secure this still more effectually, I have found it of great utility to protect it by a portion of gold-beater's skin. The skin surrounding the wound is simply moistened with a drop of water, and the gold-beater's skin is then to be applied over it and over the eschar, to which it soon adheres firmly, but from which it may be removed at any time, by again moistening it for a moment with water; the same bit of gold-beater's skin admits of being again and again reapplied in the same manner.
The other circumstances which render the eschar unadherent will be mentioned hereafter. In the mean time the fact stated [p. 6], will sufficiently establish the propriety of treating distinctly of the adherent eschar.
I now proceed to mention some other effects of the application of the caustic. The first is that, in cases in which there would be much and long continued irritability and pain, as in superficial wounds along the shin, all this suffering, and its consequences in disabling the patient, are completely avoided. A blush of inflammation forms around the eschar, but this gradually subsides without any disagreeable consequences, and the inflammation which would otherwise have been set up is entirely prevented by the due formation of the eschar.
If inflammation be previously established, it is increased, at first, by the application of the caustic. But if this inflammation be not severe, and if the eschar remain adherent, all inflammation, both that induced by the application of the caustic, and that existing previously, entirely subsides. When the previous inflammation round the ulcer is considerable, however, the application of the caustic would induce vesication, and it should in such a case of course be avoided, and another mode of treatment to be described hereafter must be adopted.
I would introduce in this place some observations on the comparative effects of healing by eschar and by scabbing. On the subject of scabbing I must refer my reader to the well known work of Mr. John Hunter. The advantage of healing by eschar over that by scabbing is quite decided. By comparative trials, I have found that whilst the scab is irritable and painful, and surrounded by a ring of inflammation, the adherent eschar is totally free from pain and inflammation; and that whilst the scab remains attended by inflammation and unhealed, the eschar is gradually separating, leaving the surface underneath completely healed. To these observations I may add that the success of the plan of healing by eschar is infinitely more certain as well as more speedy than that by scabbing.
I shall, in conclusion, briefly recapitulate the advantages of this mode of treatment. In the first place, it will be found far more efficacious and speedy than any other; secondly, it has the great advantage of saving the patient much suffering and inconvenience; and thirdly, it renders the repeated application of dressings and ointments quite unnecessary. Its utility is extremely great, therefore, where the time of the poor, the expense of an establishment, and the labours of the medical officer, as well as the sufferings of the patient, require to be considered; and it will I imagine be found of no little advantage, in all these respects, in many cases which are incident to the soldier and sailor.