Data acquisition
sEMG recordings, Pes manometry and ventilator scalars were acquired at baseline and subsequently during each intervention according to the randomization outcome [Electrical activity of the diaphragm and parasternal intercostal muscles (ICM) was measured transcutaneous using pairs of single Ag/AgCl electrodes (EasyTrode TM Pre gelled Electrodes, Multi Bio Sensors Inc, El Paso, USA). Two electrodes were placed bilaterally at the costo-abdominal margin in the nipple line, and an electrode at both the left and right second intercostal space. A common electrode was placed at the sternal level [A proximal flow sensor (VarFlex™, Vyaire, Mettawa, III, USA) was used to measure flow and Vt near the Y-piece of the endotracheal tube. Ventilator scalars were acquired using the ventilator’s analog output port. All signals were digitized with a sample frequency of 1024 Hz and stored offline (Polybench, Applied Biosignals GmbH, Weener, Germany).Patient characteristics (gender, age, weight, 24-h Pediatric RISK of Mortality (PRISM) III score, admission diagnosis and endotracheal tube size) were obtained to characterize the study population [