Bleomycin is an antineoplastic agent with potential for producing pulmonary toxicity, attributed in part to its free radical-promoting ability. Clinical and research experiences have suggested that the risk of bleomycin-induced pulmonary injury is increased with the administration of oxygen. We report a case in which the intraoperative administration of oxygen in the setting of previous bleomycin therapy contributed to postoperative ventilatory failure. Our patient recovered with corticosteroid therapy. Physician awareness of a potential interaction between oxygen and bleomycin may help reduce the morbidity and mortality related to bleomycin therapy.