Other Scientific Questions in Respiratory Diseases
Conditions
Interventions
Observation Group:None
Sponsors
Ruijin Hospital, Shanghai Jiao Tong University School of Medicine
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Inclusion criteria
Inclusion criteria: 1. The subject or their legally authorized representative provides signed and dated written informed consent, fully understands the study content, and voluntarily agrees to participate. 2. Age >= 18 years, regardless of gender. 3. Requires invasive mechanical ventilation (with mandatory indwelling endotracheal tube) under general anesthesia due to their own diagnostic or therapeutic needs, and the clinical procedures to be performed do not routinely require prophylactic antibiotic use according to clinical practice guidelines. 4. No history of acute or chronic pulmonary diseases (including but not limited to chronic obstructive pulmonary disease, bronchial asthma, lung cancer, interstitial lung disease, bronchiectasis, etc.) prior to or at enrollment, and no history of pulmonary infection within 30 days prior to enrollment. The following clinical features must be simultaneously met: (1) No evidence of pulmonary infiltrates, consolidation, cavities, or abnormal nodules (active or residual lesions) on pulmonary imaging (e.g., X-ray or CT); (2) No unexplained fever (body temperature > 38°C), with normal peripheral blood white blood cell (WBC) count; (3) No recent new-onset or worsening respiratory symptoms such as cough, sputum production, dyspnea, or tachypnea; no dry/moist rales or abnormal breath sounds on pulmonary auscultation; normal blood oxygen saturation/oxygenation indices prior to enrollment; (4) If respiratory pathogen testing is performed as part of routine diagnostic workup, results must be negative; if any pathogen test result is positive, the subject may only be enrolled after comprehensive evaluation by the investigator to rule out active infection. 5. Lower respiratory tract secretions can be collected within 24 hours following the initiation of invasive mechanical ventilation. 6. No receipt of systemic or topical medications that could significantly alter the baseline microbiota within 30 days prior to enrollment (see exclusion criteria for details). 7. Absence of diseases or conditions specified in the exclusion criteria, including immunodeficiencies.
Exclusion criteria
Exclusion criteria: 1.Diagnosis or suspected presence of any acute or chronic pulmonary disease (e.g., pulmonary infection, chronic obstructive pulmonary disease, bronchial asthma, interstitial lung disease, primary/secondary lung tumors, bronchiectasis, active pulmonary tuberculosis, etc.). 2.Receipt of any form of inhaled nebulization therapy within 30 days prior to enrollment (including but not limited to nebulized inhaled corticosteroids, antibiotics, bronchodilators, mucolytics, etc.). 3.Systemic use (oral or intravenous) of any dose of antibacterial, antifungal, or antiviral agents for any reason within 30 days prior to enrollment (including during the current hospitalization up to the time of sampling). 4.Continuous use of microecological modulators (e.g., oral probiotics, prebiotics, etc.) for more than 7 days within 30 days prior to enrollment. 5.Presence of immunodeficiency (e.g., HIV infection, post-solid organ transplantation, long-term use of immunosuppressants), or active carrier status of hepatitis B virus (HBV) or hepatitis C virus (HCV). 6.Presence of a confirmed infectious focus in the oral cavity or nasopharynx, or a recent history of oral surgery. 7.A definite aspiration event during endotracheal intubation (e.g., massive reflux of gastric contents). 8.Pregnancy or breastfeeding. 9.Age < 18 years. 10.Severe mental illness or inability to comply with study procedures. 11.Prior receipt of other investigational drugs in related clinical trials that may interfere with the interpretation of study results. 12.Refusal or withdrawal of informed consent for this study.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Microbial community structure and functional gene abundance; | — |
Secondary
| Measure | Time frame |
|---|---|
| Mechanical ventilation duration; | — |
Countries
China
Contacts
Public ContactJialin Liu
Ruijin Hospital, Shanghai Jiao Tong University School of Medicine
Outcome results
None listed