Effects of Mechanical Insufflation-Exsufflation With Optimized Settings on Wet Mucus Volume During Invasive Ventilation

"The endotracheal tube cuff will be inflated to 40 cmH2O and MI-E device will be used to deliver MI-E in automatic mode, with 4 sets of 5 respiratory cycles each and a 1-minute interval between each set.~Before initiation of the MI-E intervention protocol, the investigators will carry out a short-period test to find the appropriate MI-E settings to achieve inspiratory volumes of ≥1 liter and PEF ≥80 L/min. Concretely, inspiratory and expiratory time will always be set at 4 seconds and 2 seconds, respectively, and inspiratory flow will always be in slow mode. Once the appropriate inspiratory pressure will be found, the expiratory pressure will be initially set to exceed in 30 cmH2O the inspiratory pressure and, if required, this will be increased by 5 cmH2O until achieving a PEF ≥80 L/min with a maximum expiratory pressure of 70 cmH2O."

"Cough Assist E70 device (Philips Respironics, USA, Andover, Massachusetts) will be used to deliver MI-E in automatic mode, with 4 sets of 5 respiratory cycles each and a 1-minute interval between each set. During the 1-minute pause between sets, the patient will be reconnected to the ventilator to avoid desaturation and de-recruitment during procedures. PEEP will remain stable during the protocol.~The standard MI-E setting will consist of in-expiratory pressures of +40/-40 cmH2O, medium inspiratory flow, with 3 seconds and 2 seconds of in-expiratory time, respectively, and 1-second pause."