In the symposium on treatment with oxygen in cases of pneumonia that was presented last year at the meeting of the Association of American Physicians, Binger,1 Barach2 and Boothby3 suggested that the disrepute of such treatment could be accounted for by the ineffectiveness of former methods of administering the oxygen. They then described the newer apparatus, the oxygen chamber and the oxygen tent, by means of which it is possible to envelop the patient, or his head, in an atmosphere of any concentration of oxygen desired. They demonstrated that with atmospheres of about 50 per cent oxygen, anoxemia could usually be controlled, and the patient with pneumonia improved subjectively; the temperature and pulse often fell dramatically.
The present report is concerned chiefly with the treatment with oxygen in cases of postoperative pneumonia at The Mayo Clinic. Up to Jan. 1, 1927, oxygen had been used in only