Jiang Q, Kurz A, Zhang X, et al. - Researchers investigated whether supplemental oxygen (80% vs 30%) elevates the hazard for long-term mortality, in this post hoc study of a large multiple crossover cluster trial wherein greater than 5,000 colorectal surgeries on 4,088 adults were assigned to receive either 30% or 80% inspired oxygen during general anesthesia. They analyzed 3,471 qualifying colorectal surgeries conducted in 2,801 patients. Death incidence after a median of 3 yr was estimated to be 13% and 14% in the 80% oxygen group and in the 30% oxygen group, respectively. Findings revealed that no increase in postoperative mortality was brought about by supplemental oxygen use.