Using Electrical Impedance Tomography to Investigate the Relationship Between Airflow Rate During High-flow Oxygen Therapy and Pressure in Patients With Heart Failure Compared to Non-invasive Ventilation

Participants will be randomly assigned to Groups A and B using a computerized randomization process. Each group will undergo specific protocols for 5-10 minutes per phase. NIV will be administered in continuous positive airway pressure (CPAP) mode. The participants will be positioned in a semi-recumbent position at 45 degrees, and the EIT belt will be placed around the fifth (or sixth) intercostal space for monitoring. The EIT signals will be filtered with a cut-off frequency set at 10 beats below the current heart rate. The entire procedure is estimated to take approximately 1-1.5 hours, and recalibration will only be performed in case of significant signal abnormalities.