Bronchoscopy is a promising technology for lung and bronchus disease detection and therapy. However, this procedure is associated with a relatively high risk of hypoxemia, coughing, wheezing, and dyspnea. Despite the fact that propofol is the most commonly used agent in procedure sedation, the narrow therapeutic index remains challenging. Esketamine is the s-enantiomer of ketamine with potent analgesic and sedative properties. This study aims to test the hypothesis that adding subanesthetic esketamine to propofol is non-inferior to propofol alone for bronchoscopy on the recovery profile and discharge from the hospital.

Bronchoscopy is one of the most common procedures to detect lung and bronchus disease. The procedure is generally uncomfortable and associated with a relatively high risk of hypoxemia, coughing, wheezing, and dyspnea. Therefore, physicians are placing increasing importance on the use of procedure sedation due to the demand for comfortable medical care.

Propofol is an effective agent for sedation in bronchoscopy with rapid onset and recovery. However, the safety endpoints of propofol are not cost-effective, including injection pain, hypotension, apnea, airway compromise, and without a reversal agent. Specifically, the depressive effects on the respiratory system are more noteworthy in bronchoscopy, which may lead to hypoxia. These drawbacks may hinder functional recovery and delay the discharge time. Hence, physicians are searching for an optimal sedation regimen for bronchoscopy.

Esketamine, the s-enantiomer of ketamine, is an N-methyl-D-aspartic acid receptor antagonist with potent analgesic and sedative properties. Evidence suggested that esketamine could be used as a component of sedative regimen in many settings, such as endoscopy and endoscopic retrograde cholangiopancreatography. Nevertheless, there remains an evidence gap in the efficacy and safety of esketamine used in bronchoscopy. Therefore, we conducted this study to test the hypothesis that low-dose esketamine as an adjuvant to propofol was non-inferior to propofol alone on the recovery profile and discharge from the hospital after ambulatory bronchoscopy.

Inclusion Criteria:

1. American Society of Anesthesiologists (ASA) classification I-III;
2. Scheduled for ambulatory bronchoscopy.

Exclusion Criteria:

1. Allergic or contraindications to studying drugs
2. History of obstructive sleep apnea-hypopnea syndrome
3. History of psychiatric illness
4. History of neurological disease
5. Pre-existing memory or cognitive impairment
6. History of seizure disorders
7. Pregnancy
8. Substance abuse or intake of drugs that affect the central nervous system
9. Inability to communicate in Mandarin Chinese.
10. Illiteracy

After publication, the individual deidentified participant data underlying published results, the study protocol, and the statistical analysis plan can be accessed upon reasonable request from the corresponding author.

We would like to share our individual deidentified participant data beginning three months following the publication of the main results.

All of the individual participant data collected during the trial, the study protocol, the statistical analysis plan, and the clinical study report can be accessed with approval from the corresponding author.