This single-center randomized controlled trial will evaluate whether real-time visual feedback from electrical impedance tomography (EIT) improves the immediate distribution of lung ventilation during incentive spirometry in adults with postoperative atelectasis. Approximately 60 participants will be randomized 1:1 to receive either EIT-guided visual feedback or standardized verbal guidance during one session of 30 incentive-spirometry breaths. The primary outcome is the change in dorsal ventilation fraction from before training to 5 minutes after training. Secondary outcomes include inspiratory capacity, ventilation homogeneity, dependent silent spaces, end-expiratory lung impedance, oxygenation, in-hospital intubation or reintubation, and intervention-related adverse events.
Age 18 years or older.
Admitted to an intensive care unit or postoperative monitoring unit after major thoracic or upper-abdominal surgery; tracheal tube removed; spontaneously breathing; and clinically stable.
Alert and able to understand and follow incentive-spirometry and EIT instructions.
Bedside lung ultrasound shows atelectasis or markedly reduced aeration in dorsal or posterolateral lung regions, with the lung-ultrasound assessment recorded.
Ongoing invasive mechanical ventilation or noninvasive ventilation, or high-flow nasal oxygen when study conditions cannot be maintained stably.
Hemodynamic instability or inability to tolerate a semi-recumbent position.
Inability to cooperate with training or impaired consciousness.
Unsuitable for EIT monitoring, including an implanted pacemaker or defibrillator incompatible with the device, severe skin disease at the electrode-belt site, or known relevant allergy.