Lung Impedetiometric Modification in SBT and Extubation Failure

"After enrollment, a silicon EIT belt of proper size with 16 electrodes was placed around the patient's chest between the 4th and 6th intercostal spaces, and connected to the EIT device. All patients were ventilated in Pressure Support Ventilation (PSV) mode, with a dedicated ventilator connected to the EIT device.~We acquired 5-min EIT data records at baseline (during PSV), during the first (SBT\_0) and the last (SBT\_30) 5 minutes of SBT, and, when the patient was extubated, during spontaneous breathing soon after (SB\_0) and 30 minutes after extubation (SB\_30).~EIT and ventilator data were recorded at a sample of 20 Hz. The last 3 minutes of each record were analyzed.~We measured respiratory rate (RR); Vt changes from baseline, expressed as percent (dVt%); dEELI variations from baseline, expressed in mL; the Global Inhomogeneity index (GI); Impedance ratio (IR) and the Center of Ventilation (CoV)."