As a result of the central disorder, the vasomotor system becomes more or less incompetent, and reduction of the blood pressure follows; the peripheral and cerebral vessels are depleted, while the larger trunks within the abdominal cav ity are engorged. This explains the greater danger of a fatal issue when much blood has been lost, the medullar and spinal changes being thus accentuated.
Shock in obstetrical surgery is most apt to occur in fat, neurotic women liv ing in comfortable circumstances, and sometimes accustomed to luxury. Old primipartp are espeeially exposed to this danger. Coe iAmer. Gync. and Obstet. Jour., Apr.. '07).
Shock is not due to a paresis of the circulation. especially of the heart and arteries, but to a profound disturbance of the entire vasomotor and sympathetic systems. This disturbing influence reach the vasomotor centre through various channels, as, for instance, by direct irritation of the sympathetic nerves in abdominal operations; by crushing injury to the skeletal nerves. as in railroad injuries; and through the medium of the brain, as in sud den fright. Or two or more of these factors may unite as a causative influ ence, as in railroad injury, where the in fluence of sudden and great fright is added to the crushing of the large nerve trunks. The condition induced is es sentially an excessive vasoconstriction. Saline solution thrown into the veins recommended. The latter should be given at a temperature of 115° or 118° F. (45.9° or 47.5° C.). Thus adminis tered, the heat of the solution is brought directly to the irritated ganglia. and Va-eular •pastu is relieved. Eugene lloise ( \V York Med. Jour., April 12. 19021.
Prophylaxis.—The prevention of shock during and after operations has received of late years considerable attention. Senn prepares his patients for grave op ei ations by administering 2 ounces of whisky by the stomach or per rectum an hour before the time set for the opera tion and by injecting grain of strych nine hypodermically a few minutes be fore anaesthetizing the patient. These prophylactic measures have been found of great value in minimizing the danger from amcsthetics and the shock incident to the operation. He likewise deems it important to prevent a loss of heat, and to favor peripheral circulation by envel oping the body and limbs during the operation.
In regard to shock after abdominal operations, stress is laid upon the fol lowing points: 1. "hock is often due to
prolonged anaesthesia in a badly-venti lated room. 2. Depression of the vital powers may be due to prolonged ex posure of the patient, to wetting of the clothing, or to contact of wet towels ith the skin: the patient should be kept warm and dry. 3. Anaemia of the brain can be prevented by operating in the Trendelenburg. position. 4. Antomia of the heart can be prevented by having the arteries well filled before operation by giving large quantities of fluid dur ing the preceding day or two). by tilling the abdomen with normal salt solution during the operation, or by rectal ene mata or transfusion afterward. 5. The administration of strychnine in doses of grain for three days before and three days after the operation diminishes shock, partly because it keeps the intes tines contracted, and thus saves them from being handled, partly because it stimulates even a badly-fed heart. G. The intestines should, as far as possible, be empty at the time of operation. This can be brought about by dieting, careful catharsis. and the use of strychnine. 7. Important organs, such as the uterus, kidney, or pieces of intestine, may be removed with little shock, provided that the operation is performed quickly, with little hsutnorrhage, and without much handling or exposure of the intestines. A. Lapthorn Smith (Canada Med. Rec., May, '07).
In order that latients should be in the best possible condaion for operation, they should be prepared by moderate and judicious stimulation. Commencing six hours before the operation they re ceive from 1 to 3 teaspoonfuls of whisky in I ounce of hot water every hour until the time for operation. Two hours be fore operation 1 or 2 ounces in 4 ounces of warm normal saline solution are passed into the rectum, high above the brim. Intravenous injections of the nor mal saline solution at a temperature of 115° F., from 1 pint to 3 quarts, as may seem to be demanded by the effect pro duced. should be used if the patient has lost much blood. The pulse should be watched during the transfusion, and when the desired tension is restored the injection can be stopped. The same can be repeated again in four to twelve hours if occasion demands. Horace T. Hanks (Amer. Gymec. and Obstet. Jour., Sept., '9S).