COMBO airway plus high-flow nasal oxygen during sedated gastrointestinal endoscopy for morbidly obese adults
Combination of COMBO Endoscopy Oropharyngeal Airway and High-flow Nasal Cannula Oxygenation in Sedated Gastrointestinal Endoscopy for Morbidly Obese Patients: a Multicenter, Randomized, Controlled Clinical Trial
This test will try combining the COMBO Endoscopy oropharyngeal airway with high-flow nasal oxygen to see if it reduces low-oxygen episodes during sedated gastrointestinal endoscopy in adults with BMI 35 or higher.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 410 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | Zhejiang University Academic / other |
| Locations | 5 sites (Beijing, Beijing Municipality and 4 other locations) |
| Trial ID | NCT07175155 on ClinicalTrials.gov |
What this trial studies
Morbid obesity (BMI ≥35) carries a high risk of hypoxemia during sedated gastrointestinal endoscopy, often exceeding 40%. The COMBO Endoscopy Oropharyngeal Airway is a multifunctional device that provides an oropharyngeal airway, bite block, capnography monitoring, and oxygen delivery; this trial pairs it with high-flow nasal cannula (HFNC) oxygen. Participants undergoing gastroscopy or endoscopy lasting ≤45 minutes will receive either the COMBO device plus HFNC or HFNC alone while oxygenation and capnography are monitored. The main outcome is the incidence of hypoxemia, with additional safety and feasibility measures recorded.
Who should consider this trial
Good fit: Adults aged 18 or older with BMI ≥35 who are scheduled for gastroscopy or gastrointestinal endoscopy expected to take 45 minutes or less and who can give informed consent.
Not a fit: Patients with active upper airway infection, significant chronic pulmonary disease requiring oxygen or preoperative SpO₂ ≤92% on room air, coagulation or oropharyngeal contraindications, severe organ dysfunction, pregnancy, or breastfeeding are unlikely to benefit or may be excluded.
Why it matters
Potential benefit: If successful, the combination could meaningfully reduce episodes of hypoxemia and related complications during sedated endoscopy in morbidly obese patients.
How similar studies have performed: High-flow nasal cannula alone has shown mixed results for preventing hypoxemia in obese patients, and the COMBO airway is a recent innovation with limited published trial data, so the combined approach remains relatively untested in large trials.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Age ≥ 18 years. * BMI ≥ 35 kg/m². * Patients undergoing gastroscopy or gastrointestinal endoscopy. * The estimated duration of the procedure does not exceed 45 minutes. * Patients have signed the informed consent form. Exclusion Criteria: * Coagulation disorders or bleeding tendency (e.g., oral/nasal bleeding risk, mucosal injury, oropharyngeal obstruction) making oropharyngeal airway placement unsafe or unfeasible. * Active upper respiratory tract infection (oral, nasal, or pharyngeal), or fever (core temperature \>37.5°C). * Chronic obstructive pulmonary disease or other acute/chronic pulmonary diseases requiring long-term or intermittent oxygen therapy, or preoperative SpO₂ ≤ 92% on room air. * Severe organ dysfunction, including: Cardiac insufficiency (\<4 METs), Severe renal insufficiency (requiring dialysis), Diagnosed severe hepatic insufficiency, Increased intracranial pressure, ASA physical status ≥ IV. * Confirmed pregnancy or current breastfeeding. * Known allergy to sedatives (e.g., propofol) or medical adhesives. * Multiple traumatic injuries. * Current participation in another clinical trial. * Other conditions deemed unsuitable by the investigator.
Where this trial is running
Beijing, Beijing Municipality and 4 other locations
- Peking University First Hospital — Beijing, Beijing Municipality, China (Recruiting)
- Jinjiang Municipal Hospital — Jinjiang, Fujian, China (Recruiting)
- The First Affiliated Hospital, Zhejiang University School of Medicine — Hangzhou, Zhejiang, China (Recruiting)
- The Fifth Affiliated Hospital of Wenzhou Medical University — Lishui, Zhejiang, China (Recruiting)
- Taizhou Hospital of Zhejiang Province — Taizhou, Zhejiang, China (Recruiting)
Study contacts
- Study coordinator: Diansan Su, Chief Physician
- Email: diansansu@yahoo.com
- Phone: +8618616514088
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.