Patients will be ventilated with driving pressure-guided ventilation with VT 6-8 ml /kg of predicted body weight, and after recruitment, we will return to the baseline PEEP 5 cmH2O that will be increased by 2 cmH2O until reaching the lowest possible driving pressure for every patient. Each PEEP level will be maintained for ten respiratory cycles and DP will be calculated at the last cycle.

Patients will be ventilated with protective lung strategy with VT 6-8 ml /kg of predicted body weight, after recruitment we will return to PEEP of 8-10 cm H2O that will be maintained until the end of surgery.

Patients will be ventilated with VT 6-8 ml /kg of predicted body weight, after recruitment we will return to physiological PEEP of 5 cm H2O that will be maintained until the end of surgery.

The lung ultrasound score between 0 and 3 (0 = normal A lines, 1 = multiple separated B lines, 2 = coalescing B lines or light beam, 3 = consolidation). The aeration score will be built by the sum of the scores of the 12 segments, with a minimum of 0 and a maximum of 36 according to the aeration loss.

The primary outcome will be the change in Lung Ultra Sound Score between 0 and 3 (0 = normal A lines, 1 = multiple separated B lines, 2 = coalescing B lines or light beam, 3 = consolidation) from the base line.

Lung compliance is a measure of the expansion of the lung.