Early PP Monitored by EIT in Patients With ARDS

Early Prone Positioning Monitored by Electrical Impedance Tomography in Patients With Acute Respiratory Distress Syndrome

Acute Respiratory Distress Syndrome (ARDS) is a syndrome characterized by respiratory distress and refractory hypoxemia caused by pulmonary and extra-pulmonary factors. Despite improvements in diagnosis and treatment in recent years, the mortality rate of severe ARDS is still around 40%. The distribution of lung lesions in ARDS patients is significantly gravity-dependent. Even with lung-protective ventilation strategies, tidal volume is concentrated in the ventral lung region, leading to ventilator-associated lung injury. Prone position ventilation can increase ventilation to the dorsal lung tissue and improve the ventilation-perfusion ratio, thus improving oxygenation. During prone position ventilation in ARDS patients, lung-protective ventilation strategies should be maintained, but with different respiratory mechanics from the supine position, requiring adjustment of ventilator parameters. Electrical Impedance Tomography (EIT) technology can be used for bedside monitoring of mechanically ventilated patients, providing real-time feedback on the patient's ventilation status and having great potential for clinical applications. Investigators believes that EIT monitoring during prone position ventilation in ARDS patients can individualize lung-protective ventilation strategies, minimize alveolar overdistension and collapse, improve the weaning success rate of invasive ventilation, and ultimately improve patient prognosis.

acute respiratory distress syndrome, prone position, electrical impedance tomography, mechanical ventilation

During prone ventilation, the PEEP level is adjusted based on EIT monitoring. The optimal PEEP is the lowest sum of collapse and overdistension percentages

After weaning from invasive mechanical ventilation lasting more than 48 hours, continuation with either high-flow nasal cannula (HFNC) or non-invasive ventilation (NIV).

Inclusion Criteria: Age ≥ 18 years old； Meets the diagnostic criteria for ARDS according to the 2012 Berlin definition； Intubation with invasive mechanical ventilation time < 36 hours； PaO2/FiO2 < 150mmHg. Exclusion Criteria: Contraindication to the prone position; Contraindication to the EIT; Patients have received extracorporeal membrane oxygenation treatment.

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