Lung US for PEEP Optimization in Robotic Radical Prostatectomy or Cystectomy Patients

After endo-tracheal intubation; A PEEP of 4 cmH2O will be initially used till 5 min after pneumoperitoneum. Then The PEEP will be adjusted in a stepwise approach after performing bedside lung ultrasound. The PEEP will be increased by 2 cmH2O until no lung collapse is detected. Lung ultrasound will be repeated 5 min after every change in the PEEP with a maximal PEEP of 12 cmH2O.

Volume-controlled ventilation (VCV) mode; with a tidal volume of 6 mL/kg of ideal weight, inspiratory : expiratory ratio 1: 2, PEEP 4 cmH2O, respiratory rate adjusted to keep end-tidal carbon dioxide tension (EtCO2) between 35 and 40 mm Hg, and inspired oxygen fraction of 50%.