Potential Biomarkers and Pathogenic Mechanism for Reflux Aspiration-induced Lung Injury.

Based on whether the patient meets the diagnosis of aspiration pneumonia.

Performing bronchoscopy.

Local pulmonary ventilation and perfusion are measured by electrical impedance tomography (EIT). For perfusion imaging, 10 ml of 5% saline is injected as a central venous bolus. The matching of ventilation and perfusion reveals intrapulmonary shunting.

According to the physician's judgment and the family members' consent, the patient is administered nitric oxide inhalation at a dosage of 20-30 parts per million (ppm).