Comparison of two supplemental oxygen methods during gastroscopy with propofol mono-sedation in patients with a normal body mass index

Background: Hypoxemia due to respiratory depression and airway obstruction during upper gastrointestinal endoscopy with sedation is a common concern. The Wei nasal jet tube (WNJT) is a new nasopharyngeal airway with the ability to provide supraglottic jet ventilation and oxygen insufflation via its built-in wall channel. The available evidence indicates that with a low oxygen flow, compared with nasal cannula, the WNJT does not decrease the occurrence of hypoxemia during upper gastrointestinal endoscopy with propofol sedation. To date, there has been no study assessing the performance of WNJT for supplemental oxygen during upper gastrointestinal endoscopy with sedation when a moderate oxygen flow is used.

Aim: To determine whether the WNJT performs better than the nasal prongs for the prevention of hypoxemia during gastroscopy with propofol mono-sedation when a moderate oxygen flow is provided in patients with a normal body mass index.

Methods: This study was performed in 291 patients undergoing elective gastroscopy with propofol mono-sedation. Patients were randomized into one of two groups to receive either the WNJT (WNJT group, n = 147) or the nasal cannula (nasal cannula group, n = 144) for supplemental oxygen at a 5-L/min flow during gastroscopy. The lowest SpO₂ during gastroscopy was recorded. The primary endpoint was the incidence of hypoxemia or severe hypoxemia during gastroscopy.

Results: The total incidence of hypoxemia and severe hypoxemia during gastroscopy was significantly decreased in the WNJT group compared with the nasal cannula group (P = 0.000). The lowest median SpO₂ during gastroscopy was significantly higher (98%; interquartile range, 97-99) in the WNJT group than in the nasal cannula group (96%; interquartile range, 93-98). Epistaxis by device insertion in the WNJT group occurred in 7 patients but stopped naturally without any treatment. The two groups were comparable in terms of the satisfaction of physicians, anesthetists and patients.

Conclusion: With a moderate oxygen flow, the WNJT is more effective for the prevention of hypoxemia during gastroscopy with propofol mono-sedation compared with nasal prongs, but causing slight epistaxis in a few patients.