 Recruitment maneuver RM is performed within 10 min on arrival in the CICU. Patient must be stabile in hemodynamic parameters, including volume status. PEEP is set to 20 cm H2O, pressure controlled ventilation with peak pressure 40 cm H2O for 30 s 5 inspirations, thereafter PEEP-trial starting from 15 cm H2O for optimal PEEP using the Open Lung Tool Maquet Flow-i software. During the PEEP-trial, VKTS for tidal volumes of 6 mlKg is used. 