Stovaine and alypin are among the latest synthetic substitutes for cocaine. The latter seems to offer promise of usefulness.
Adrenalin may be added to any of these solutions in proportion of 1 per cent. of a 1 to 1000 solution, and will have a beneficial effect in all cases.
INTRASPINAL COCAINIZATION.
The intraspinal injection of remedies was first suggested by Corning, of New York, in 1885; it remained, however, for Bier to perfect the technique in 1899, and to make it so popular that the same maneuver has been practised for various other purposes; as, for instance, for withdrawal of cerebrospinal fluid in cases of hydrocephalus, etc., or the injection of tetanus antitoxin. (See chapter on [Tetanus].)
The intent in this use of cocaine is to spread the solution over the surface of the cord and beneath the arachnoid. For this purpose a needle about 4 inches in length, with a point not too sharp, preferably gold or platinum plated, is used; with this also a syringe which will hold 2 to 4 Cc., which can be firmly, yet easily, attached to the needle. The accompanying illustration ([Fig. 46]) will give an idea of the technique. The patient should be seated leaning forward so as to curve the back and open the intervertebral spaces. A sterilized towel is stretched tightly across the back from one iliac crest to the other; its upper edge should then pass just over the spinous process of the fourth lumbar vertebra. The injection is usually practised between the second and third lumbar spines, or between the third and fourth; the latter having been identified, the former are easily made out. The needle is entered about 1 Cm. to the right of the middle line and passed forward, inward, and upward, to a depth of 7 or 8 Cm. in the ordinary adult, until the resistance offered by the tissues is felt to have been passed and the point to have entered a cavity. If the needle has been passed alone the escape of a drop or two of cerebrospinal fluid will indicate that the spinal canal has been entered; if the syringe is attached to the needle the piston should be withdrawn in order to show the same result. It is possible to practise this operation with a patient in the recumbent position, but it is done more easily as above outlined. The skin may be frozen by the freezing spray, or may be anesthetized by the local injection of cocaine solution with the ordinary hypodermic syringe.
It is astonishing what beneficial effects can be gained from the use of a small amount of cocaine. It is rarely necessary to use more than 0.03 (¹⁄₂ grain) of pure cocaine in order to procure analgesia of the entire lower part of the body.
Beta-cocaine or tropacocaine may be used for the same purpose, in double this amount, but they do not give as reliable results. Morton, of San Francisco, has suggested that ¹⁄₂ Gr. powders of cocaine be wrapped in such a way that they can be repeatedly sterilized by a heat of 200° F., and that one of these be dropped into the syringe barrel, that this be attached to the needle, and the cocaine itself be dissolved in the cerebrospinal fluid withdrawn through the latter, and then thrown back again. This is probably the neatest and most serviceable method yet devised, and its originator has assured the writer that with 1 Gr. of tropacocaine used in this way, thrown into the spinal canal with considerable force, i. e., in such a way as to more completely distribute it, he has been able to practise operations even upon the tongue with little or no pain to the patient. The solution used for this purpose should be sterilized, also the needle, the syringe, the patient’s skin, and the operator’s hands. The water with which the cocaine solution is made should be first pure, then measured, and the solution made in such strength that not more than the amount indicated above will be used. This should then be again heated, but not quite to the boiling point, since cocaine solutions are impaired by too much heat.
Fig. 46
Technique of intraspinal injection.