Mini-dose Dexmedetomidine-Esketamine Supplemented Analgesia in Patients at High-risk of OSA

Who can take part

• Aged ≥18 years but ≤80 years
• Preoperative diagnosis of OSA, or judged to be at moderate-to-high risk of OSA according to the STOP-Bang Questionnaire
• Scheduled to undergo thoracoscopic or laparoscopic surgery under general anesthesia, with an expected surgical duration of ≥1 hours, and required patient-controlled intravenous analgesia (PCIA) after surgery

Who cannot take part

• Previous history of schizophrenia, epilepsy, Parkinson disease, or myasthenia gravis
• History of drug or alcohol dependence, or sedative or hypnotic therapy within 1 month before surgery
• Contraindications to high-flow nasal cannula therapy (such as mediastinal emphysema, shock or hypotension, cerebrospinal fluid leakage, nasosinusitis, otitis media, or deviation of nasal septum)
• Expected intensive care unit (ICU) admission with tracheal intubation after surgery
• Diagnosed as central sleep apnea syndrome
• History of schizophrenia, or having antipsychotic drugs (including antidepressants or anxiolytics)
• Inability to communicate in the preoperative period because of coma, profound dementia, or deafness
• Sick sinus syndrome, severe sinus bradycardia (<50 beats per minute), or second-degree or above atrioventricular block without pacemaker
• Other conditions that are considered unsuitable for study participation
• Severe hepatic dysfunction (Child-Pugh class C), severe renal dysfunction (requirement of renal replacement therapy), severe heart dysfunction (preoperative New York Heart Association functional classification ≥3 or left ventricular ejection fraction <30%), or ASA classification IV or above
• Contraindications to ketamine (such as hyperthyroidism, pheochromocytoma, or glaucoma)