THE EFFECT OF ANAESTHESIA ON ANAPHYLAXIS IN GUINEA-PIGS.

The effect of several anaesthetics on anaphylaxis was tested on guinea-pigs sensitized to milk and challenged by intravenous injection or inhalation. No protection from fatal anaphylaxis was conferred by halothane, diethyl ether volatilized by air, nitrous oxide and trichloroethylene with oxygen, or pentobarbitone sodium when the animals were challenged by intravenous injection, and death was demonstrated to be due to asphyxia following bronchial constriction. However, a mixture of carbon dioxide and oxygen protected the sensitized animals from the immediate fatal effects of intravenous challenge but it did not suppress all signs of anaphylaxis. Diethyl ether volatilized by air or oxygen provided some protection from challenge by inhalation, but none was provided by halothane or pentobarbitone sodium. Anaphylaxis may be modified but its fatal outcome not prevented by the majority of the anaesthetics used. It is considered that individuals specifically sensitized to some article of their diet may die of anaphylaxis following inhalation of vomit containing the antigen when they are deeply asleep or anaesthetized.