Continuous in-vivo monitoring of arterial oxygen tension in a patient treated with bleomycin.

Patients receiving bleomycin therapy may develop pulmonary fibrosis. The risk of fibrosis is increased by the administration of general anaesthesia and fatal cases with pulmonary lesions resembling those of "oxygen toxicity" have been reported. The causes are not entirely clear but the enriched inspired oxygen given intraoperatively or postoperatively has been identified as an etiological factor. Optimal intraoperative management thus requires the administration of the lowest inspired oxygen fraction (FIO2) compatible with adequate oxygenation. To achieve this aim safely, continuous in vivo monitoring of arterial oxygen tension would be preferable to intermittent sampling of blood gases. We report the successful management of a patient undergoing thoracotomy following bleomycin therapy using an intravascular PO2 sensor to monitor arterial oxygen tension continuously. The uses and limitations of the PO2 sensor are discussed.