If any ointment has been used about the fissure, the anus should be subjected to a hot-water douche before using the cocaine, as cocaine will not exert its anæsthetic influence on a greasy surface.[[27]] For this purpose Martin's irrigator (Fig. 8) answers admirably. The parts should subsequently be dried thoroughly with cotton or a sponge. A convenient sponge or cotton mop holder is shown in Fig. 10.
Fig. 10—Rectal Sponge-Mop Holder.
Among the different remedies that have been used for the local treatment of fissure of the anus may be mentioned the following: Nitrate of silver; acid nitrate of mercury; fuming nitric acid; carbolic acid; sulphate of copper; the actual cautery, etc.
Of these topical applications, the nitrate of silver is the best. Its effects are various: it lessens or entirely calms the nervous irritation which is so important a factor in producing spasmodic contraction of the sphincters; it shields the raw and exposed mucous surface, by forming an insoluble albuminate of silver; it destroys the hard and callous edges of the ulcer, and tends to remove the diseased and morbid action of the parts.
The form in which I usually employ this salt is in solution (from ten to thirty grains to the ounce). To attain the best results, the solution should be used once in twenty-four or forty-eight hours, according to circumstances. It may be applied by means of cotton attached to a silver applicator or cotton-holder (Fig. 11), or to a piece of wood. The application is made by separating the margins of the anal orifice with the thumb and index finger of the left hand, and introducing into the anus the probe charged with the solution.
Fig. 11—Cotton-Applicator.
According to Bodenhamer,[[28]] if the ulcer is more than one-third of an inch above the margin of the anus it will be necessary to use the speculum.
The solution is to be applied to the fissure only; a few drops are all that will be required. If thorough local anæsthesia has been induced by the use of cocaine, the application of the silver salt produces little if any suffering; for by the time the anæsthetic has lost its effect the acute pain caused by the nitrate of silver will have passed away.