Prior to intubation with this new device, the investigators will measure the TTK sealing pressure, setting the respirator to manual mode, closing the expiratory valve to 40 cmH2O, and adjusting the fresh gas flow to 3 litres. The pressure at which audible leakage occurs will be measured. If the pressure exceeds 40 cmH2O, the test will be considered over, and this latter value will be recorded as the TTK sealing pressure (> 40 cmH2O).