Effects of non-intubation anesthesia based on a fentanyl-reduced regimen on hypoxemia during bronchoscopy for older patients: study protocol for a randomized controlled trial.

Background: Older patients are more likely to suffer from cardiopulmonary events during sedation-based bronchoscopy. It is important to balance the inhibition of stress and cardiopulmonary function, particularly for the elderly. This randomized controlled trial aims to investigate a fentanyl-reduced regimen on hypoxemia during bronchoscopy for older patients. Methods: Eligible patients will be randomly allocated to the study group or control group. Medication regimen for the study group is remimazolam 0.2 mg/kg + esketamine 0.3 mg/kg + fentanyl 0.5 µg/kg, whereas those in the control group will receive remimazolam 0.2 mg/kg + fentanyl 1.5 µg/kg. Remimazolam 0.05 mg/kg will serve as top-ups for both groups. The primary outcome is the incidence of hypoxemia during bronchoscopy. The secondary outcomes include rates of successful examination, awakening time, discharge time, quality of recovery, satisfactory scores of patients and the endoscopist, incidences of hypotension or hypertension and body movement (cough, swing of the limbs, etc.). Discussion: The present study aims to assess the effects of a fentanyl-reduced protocol on bronchoscopy for older patients. The results are supposed to be that the fentanyl-reduced regimen can provide sufficient sedation for geriatric bronchoscopy with fewer adverse events, which is worthy of clinical adoption. Trial Registration: The trial has been registered at Chinese Clinical Trial Registry (ChiCTR2400084672).