Page:Collier's New Encyclopedia v. 09.djvu/53

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SPINAL ANESTHESIA 27 SPINAL MENINGITIS part of the body. Cocaine was used in the earliei' experiments, but eucaine, novocaine and stovaine were later sub- stituted as being less toxic. Jonnesco used a mixture of stovaine and strych- nine. When only the lower part of the body is to be operated on, it is possible to anesthetize that part only, the patient retaining consciousness throughout the operation. Generally speaking, spinal anesthesia is more common on the Euro- pean continent than in the United States or in England. In the latter countries it is looked upon only as a substitute for general anaesthesia. It frequently pro- duces undesirable after effects, including general weakness, nausea, and even par- tial temporary paralysis. Jonnesco's method of application is looked upon as dangerous, although it is claimed in Eu- rope that it is no more dangerous than E:eneral anesthesia and that the per- centage of deaths is even less. It is possible that its use may develop as im- provements in methods of application are worked out. SPINAL CORD, the name given in anatomy to the great cord or rod of nervous matter which is inclosed within the backbone or spine of vertebrates. The spinal cord in man, which is from 15 to 18 inches long, has direct connec- tion with the brain by means of the medula oblongata, and passes down the back till it terminates in a fine thread at the level of the first lumbar vertebra. Lodged in the bony vertebrae it varies in thickness throughout, and like the brain is invested by membranes called respectively pia mater and dura mater. Situated between these two are the deli- cate layers of the arachnoid membrane, inclosing a space which contains the cerebrospinal fluid. Besides these pro- tective coverings there is also a packing of fatty tissue which further tends to diminish all shocks and jars. The spinal nerves, to the number of 31 on each side, pass out from the cord at regular in- tervals, pierce the dxira mater, escape from the backbone, and ramify thence through the soft parts of the body. Eight pairs pass off in the region of the neck called the cervical nerves, 12 pairs are dorsal, 5 are lumbar, and 5 sacral, while the last pair comes off behind the coccyx. In its structure the spinal cord consists of gray and white matter. The gray matter, which is characterized by large cells, is gathered in the center into two crescent-shaped masses connected at the central part of the cord. The white matter, consisting mainly of fibers, is outside of and surrounds these gray crescents. In its functions the spinal cord forms a tract along which sensory impressions may pass to the brain, and along which motor impulses may travel to the muscles. It is besides a great re- flex center. See Brain: Nerve: Spine. SPINAL MENINGITIS, an inflamma- tion of the meninges, the membranes covering the spinal cord. The mem- branes are three in number: the pia mater, which is in contact with the sub- stance of the cord; the dura mater, which serves as a lining to the spinal canal; and the arachnoid, a webbed structure between the pia mater and the du7-a mater. An inflammation af- fecting the meninges of both the brain and the cord is called cerebrospinal meningitis. In spinal meningitis all three membranes are usually involved. Acute spinal meningitis is often caused by sunstroke, exposure to cold, and in- jury to the spine, and is occasionally a complication in cases of scarlatina, typhoid fever and pneumonia. The pre- liminary symptoms include pain, chill, fever, vomiting and a general sense of disarrangement. The shooting pains in the region of the cord are rendered more acute when the back is touched or moved, and the pain is transmitted to those parts of the body with which the cold is immediately connected, and in extreme cases the paroxysms may lead to a chronic bending of the spinal col- umn. After a period of fever lasting some days a condition of paralysis super- venes which may result in death from exhaustion. Where the patient recovers convalescence is usually protracted over several months, but where the illness is long drawn out complications in the renal and vesical regions may lead to a fatal issue. The pia muter in these cases becomes congested and reddish with the accompaniment of hemorrhages. There is an issue of matter varying in color from gray to green on the surface of the pia, with congestion of the spinal fluid. Inflammation may pass from one membrane to another, as well as to the substance of the spinal cord, and free action may be prevented to such an ex- tent that the membranes may be held together. The malady may be acute or chronic, and the chronic differs from the acute chiefly in the fact that the proc- cesses are prolonged, and there is an absence of fever. In acute cases, com- plete rest in bed is the first requisite, care being taken that there is no pres- sure on the affected parts. The bowels should be kept clean, the spine should be cupped, and ice afterward applied. Where the pain is great suitable drugs may be administered to give relief. Re- course may be added to external coun- ter-irritants to assuage the pain in the