Hypoxemia is considered to be the most important challenge during one-lung ventilation (OLV). Recent studies, however, have shown that one-lung ventilation can involve some lung damage and can therefore be per se a cause of hypoxemia. OLV can be associated to an injury: but the techniques used to improve oxygenation may also damage the lung. A new ventilator approach should be used and applied with regards to what is so far known in terms of "lung protection" also during OLV.