The cause of serum anaphylactic shock and some methods of alleviating it

Abstract

Last July a series of experiments was begun to find out, if possible, the main cause of anaphylactic shock. It was already known that the phenomena were primarily respiratory, but it was not proven whether the origin of the trouble was central or peripheral. In order to clear up this point a number of guinea pigs were given artificial respiration, and their blood-pressure recorded from the carotid by means of a mercury manometer. It was proven that the cause of death is asphyxia which is peripheral in origin. Some animals died in spite of all that could be done for them while in others the symptoms were less acute and yielded to certain forms of treatment. In the more acute forms of anaphylactic shock the respiratory muscles of the chest and the diaphragm act without the lungs fulfilling their function. That the latter do not function is shown both by the slight motion of the respiratory tambour, connected with the trachea, and by the dark venous color of the carotid blood. In spite of the dyspneic movements the animal gradually dies from weak heart resulting probably from the lack of oxygen supply. In the less acute forms of shock, however, we were able to save the animals by artificial respiration, recovery being indicated by the carotid blood assuming its normal color, the blood-pressure returning to normal and instead of the spasmodic action of the diaphragm there ensued an even, rhythmic respiration. It was also noted that in those cases not yielding to artificial respiration the chest became fixed and the rhythmic action of the bellows caused no change in the position of the walls of the chest cavity.