(1) Lung reexpansion provoked severe oxidative stress. (2) The degree of the amount of generated oxygen free radicals was associated to the duration of OLV. (3) Patients with lung cancer had a higher production of oxygen free radicals than normal population. (4)Tumor resection removes a large oxidative burden from the organism. (5) Mechanical ventilation and surgical trauma are weak free radical generators. (6) Manipulated lung tissue is also a source of oxygen free radicals, not only intraoperatively but also for several hours later.

Protracted (>1h) OLV should be considered a potential cause for cardiovascular complications through the generation of severe oxidative stress due to lung reexpansion.