THE NATURE OF CIRCULATORY COLLAPSE INDUCED BY SODIUM NITRITE 1

Abstract

The study to be reported was undertaken with the purpose of throwing light on the mechanism of vasomotor collapse in man. During a previous investigation (1), it was noted that small doses ofsodium nitrite, which in normal subjects would produce no symptoms and slight if any circulatory changes in the prone position, would in the up- right position lead to progressive vasomotor col lapse, often terminating in syncope. Return to the prone position was followed by immediate recovery without ill effects. By varying the dose of sodium nitrite and the angle of tilting the body, the duration as well as the degree of the circulatory collapse could be regulated. This method, then, offered an opportunity of recording observations on vasomotor collapse under well-controlled experimental conditions. This seemed particularly desirable in view of the fact that the study of vasomotor collapse, as it occurs in various diseases, is difficult because it develops unexpectedly in seriously ill patients and often terminates fatally.