Perfluorocarbon (PFC) Inhalation Treatment of Acute Lung Injury/Acute Respiratory Distress Syndrome

Inclusion Criteria: * Age: 18-75 years old * Some clear risk aetiological agents of acute respiratory distress syndrome * Acute onset, with corresponding clinical manifestations * PaO2/FiO2 ≤ 300mmHg * Chest radiograph or chest computerized tomography prompting bilateral pulmonary infiltrate shadow * pulmonary capillary wedge pressure (PCWP) ≤ 18 mmHg or clinical cardiogenic pulmonary edema can be excluded * respiratory rate (RR) ≥ 30bpm and (or) respiratory distress * requiring tracheal intubation or tracheostomy for invasive mechanical ventilation * or have received invasive mechanical ventilation time ≤ 3 days Exclusion Criteria: * Age: \< 18 years old or \> 75 years old * During the early stage of the treatment, the use of mechanical ventilation for more than 3 days other than ALI/ARDS for reasons * Lung parenchyma and airway surgery carried out within 30 days of the screening period * Severe arrhythmia and myocardial ischemia after cardiopulmonary resuscitation * Systolic blood pressure \< 90 mm Hg, and can not maintain its stability with intravenous infusion and vasopressor drugs * Intubation due to interstitial lung disease (E.g., sarcoidosis, idiopathic pulmonary fibrosis) * Any active pneumothorax or mediastinal emphysema * Risk factors leading to the death within 3 months in addition to ALI/ARDS during the screening period (E.g., end-stage cancer) * Of perfluorocarbons' allergies * Pregnant, breastfeeding women * Attending other clinical trial within 30 days of the screening period * Severe organ dysfunction (Marshall score ≥ 3 or Sequential Organ Failure Assessment（SOFA） score≥ 3, including serious liver and kidney dysfunction, upper gastrointestinal hemorrhage, etc.) * Acute Physiology and Chronic Health Evaluation（APACHE） II score ≥ 30, high risk of death * The researchers consider other situations not suitable for the case to participate in the study