Ethylene in combination with oxygen as an agent of anesthesia was first used clinically at the Presbyterian Hospital, Chicago, March 14, 1923. Since these original clinical studies, ethylene-oxygen gas as an agent of anesthesia and analgesia has become quite widely accepted. There have been numerous reports of experimental and clinical studies of the effects of this anesthesia on the various biologic and physiologic processes; but, to my knowledge, no one has ever conducted a carefully controlled study of its effects on the normal human being, without any complicating factors such as surgical trauma, preanesthetic medication, pathologic conditions and mental anxiety due to an impending operation being present.
The surgical service of Letterman General Hospital was interested in knowing the effects of ethyleneoxygen anesthesia on the normal human being when there were no other complicating factors present. As an approach to this problem, it was decided to anesthetize a number of