The Actual Cautery.
—In some one of its improved forms the Paquelin cautery has replaced all the old cruder methods of cauterization. When properly employed its counterirritant effect can be made most serviceable for the relief of pain, or for any desired form or degree of counterirritation. Applied over the upper abdomen, with the lightest possible touch, in such a way as to deserve the term “flying cautery,” it will sometimes afford great relief in nausea and vomiting, especially when these symptoms are purely reflex.
Used over the course of the larger nerves it does much to relieve the pain of neuritis; while over swollen joints and swollen testicles it affords great relief from the pain of chronic arthritis and chronic or acute epididymitis. In deep-seated congestions and inflammations ignipuncture may be made with a small cautery point, by plunging it through the skin into the underlying tissues, and into bone. The relief of tension as well as the counterirritation will give great relief. When practised in this manner local or general anesthesia may be used. Except when thus used it will rarely be necessary to do more with it than to disturb the exterior of the skin. When skilfully used this can be done with the production of very little pain.
PARACENTESIS.
Paracentesis is the technical name given to the act of tapping, or the withdrawal of fluid from any of the closed cavities of the body. It includes aspiration, tapping, and incision.
Aspiration.
—By aspiration is meant the removal of fluid without the admission of air; it comprises the use of a suction apparatus, usually known as an aspirator, which may be had in various forms and sizes. A small so-called exploring syringe will answer for small cavities, while for large collections of fluid, such as may be met with in the thorax, more elaborate apparatus is used, consisting of a suction pump connected by tubing with a bottle in which the vacuum is produced. By another tube this bottle is connected with a hollow needle used for the withdrawal of the fluid. Absolute asepsis should be observed, even in this minor procedure. The skin should be cleansed, and the needle, instrument, and hands should be sterilized. The pain of puncture may be prevented by use of the freezing spray, of cocaine injected locally, or by touching the skin with a drop of pure carbolic acid. The vacuum is commonly resorted to in the removal of fluid from the thorax, the spinal and the cranial cavities, and from joints; also in small collections of pus in any part of the body.
Tapping.
—Tapping means a somewhat similar procedure with a larger instrument known as a trocar and a surrounding cannula, without the aid of the vacuum. Precaution should be taken in every regard that the instruments and the parts should be sterilized.
The trocar, inserted in the cannula, should be plunged quickly into the cavity at the site selected. Considerable resistance will be offered by the skin. If the trocar be small it is enough to anesthetize the skin; if large, a small incision will permit of its better use. The instrument makers have provided cannulas of various descriptions, to which tubing may be attached, so that the fluid may be conducted into a suitable receptacle, and wetting the patient avoided. It is well to draw the skin aside and not to make the instrument pass directly into the cavity to be tapped unless it contain pus and it be desired to keep it open. If this precaution is taken the skin will cover the deep opening after it slips back into its position, and will act as a valve to prevent leakage. In this way infection may be avoided.