The bacteriological side of this subject has been investigated by numerous observers, particularly Dr. E. R. McGuire, attached to the Buffalo Surgical Clinic, who reached the following conclusions: Absolute sterility of the hands is unattainable, but as toward this result nothing takes the place of long and vigorous mechanical scrubbing under aseptic precautions; the use of antiseptics on the skin is of questionable value and often distinctly harmful; the operator whose hands perspire freely should wear gloves in every case; the use of rubber gloves is not ideal, but gives the nearest approach to it.
No material should be used which is so harsh that it will injure or destroy the epithelial cells either upon the operator’s hands or upon the patient’s skin.
Solutions of gutta-percha in its different solvents, or of collodion in acetone, have been suggested as forming a covering for the hands by quickly drying upon the skin. The merit of these preparations is questionable, and the length of time required to dissolve the coating makes them impracticable. They have found little favor among surgeons.
Next to the sterilization of the parts to be operated, and the hands, may be considered treatment of septic tissues or fluids and protection against further infection. Clean and uninfected tissues need no other precautions than those already described, plus extra care in hemostasis, in order that there be no clot left in which germs may find a nidus, and the careful closure of the wound in such a way that no cavities or “dead spaces” may be left in which blood may later collect. Surgeons generally agree that the less clean tissues are handled and the less contact they undergo with foreign materials the more readily they heal. The ideal fluids with which to cleanse parts or to wash away blood clot are sterile salt solution and boiled water. Antiseptic solutions should not be used upon healthy tissue; but when abscess cavities have been opened and when pus or other infectious material have come in contact with fresh raw surfaces, every effort should be made to overcome its effects. It is customary in abdominal operations to “wall off” the site of a pus focus so that contamination of adjoining surfaces may be avoided, by placing gauze packing around it. Other expedients, e. g., the use of a rubber dam in any of its modifications, which will aid in this purpose, should be adopted. Upon brain surfaces, as upon the ruptured perineum, and in vaginal, rectal, and numerous other operations, a continuous fine stream of salt solution may be directed with great benefit.
An abscess of any kind, no matter where located, should be thoroughly cleansed, its cavity disinfected, and easy access made to the outer wound. The interior of such cavities should be scraped with a sharp spoon. After curetting, a thorough washing or swabbing, often with the use of hydrogen dioxide, will often prove serviceable. Even a treatment of this kind does not afford as complete disinfection as may be secured by free application of pure carbolic acid or of a strong solution of zinc chloride (50 per cent.). The effect of this is not only to more completely sterilize, but to so sear the cauterized surfaces as to make them incapable of absorption. Excess of the caustic should be wiped away, or antidoted, in the case of carbolic acid by further swabbing with alcohol, or in the case of zinc chloride by merely washing out. Such a surface should heal naturally after sloughing, yet it is rarely safe to completely close such a cavity. A light packing of clean gauze, or, as the writer is fond of using it, of gauze sopped in balsam of Peru, will permit such a cavity to quickly close by the granulation process without further disturbance. Bone cavities, especially, are well treated with zinc chloride, it being difficult to so thoroughly disinfect such a focus that it may be safely closed without drainage; or they may be filled with bone chips or paraffin.
Visible tissue which is sure to slough should be removed with scissors or the sharp spoon, in order to save valuable time. Sometimes the actual cautery may be used to great advantage, as in chancroidal buboes, where every particle of raw surface will be infected by the pus which flows over it, and where it is advisable to cauterize not merely the suppurative focus, but everything which may come in contact with its pus.
Instruments.
—Instruments are now all made of metal, usually nickel-plated, which will stand at least a certain amount of exposure to heat. It is not sufficient, however, to sterilize instruments alone, but basins, irrigator nozzles, and everything else which may be wanted during the course of an operation should be equally prepared for it. Inasmuch as hard rubber does not well stand even boiling water, instruments should be made, so far as possible, of metal or of glass. Boiling water, or “live” steam, are universally employed for this purpose; while to the water is often added 1 per cent. of ordinary washing soda, which enhances its serviceability. Fifteen to twenty minutes’ actual boiling, or its equivalent, will be sufficient for ordinary purposes. All instruments, such as knives and scissors, deteriorate after repeated use in this way and need to be frequently sharpened. Catheters also may be sterilized by boiling and should be constantly kept exposed to some volatile antiseptic, such as formalin (see [above]). Sterile material should be used upon the inhalers, and the metal parts of these, as well as mouth-gags, hypodermic syringes, and the like, should all be boiled.
Dressings, etc.
—Not only the dressings which are to be employed after an operation, but the gauze, the cotton, or the sea-sponges which may be used during the same should have been twice sterilized either by dry heat or steam, in order to ensure security. No absorbent material should be packed tightly if it is to be subjected to steam, as it is not easily penetrated, even under pressure. Moreover, not only these materials but the sheets, gowns, aprons, towels, splints, and everything which may come into near approach or actual contact with the wound should be prepared in the same way. After sterilization all these materials should be enclosed in germ-proof, sterile wrappers of some kind or in sterile jars or boxes.