Clinical Research Directory

Inclusion Criteria: 1. Patients undergoing elective thoracoscopic surgery under general anesthesia, and patients with moderate to severe pain requiring opioids or opioid-non-opioids combined analgesia after surgery as assessed by the investigator; 2. 18 to 65 years of age, male or female; 3. Body mass index (BMI) between 18-30 kg/m ² (BMI = body weight (kg)/height ² (m ²)), including borderline values; 4. Modified Mahalanobis score \< III; 5. ASA grade I \~ III; 6. Voluntarily signed informed consent. Exclusion Criteria: 1. Inability to understand the nature, significance, possible benefits, possible inconveniences and potential risks of the trial, or inability to understand the study procedures and pain-related assessment methods; 2. Patients who cannot accept the postoperative analgesia specified in the protocol; 3. Clinician judgment: liver and kidney dysfunction has clinical significance (ALT and AST \> 2 times the upper limit of normal; BUN and/or Urea \> 2 times the upper limit of normal, Cr \> 2 times the upper limit of normal; dialysis treatment within 28 days before surgery), or coagulation dysfunction has clinical significance (PT or APTT or TT \> the upper limit of normal), or poor blood pressure control (sitting SBP \> 160 mmHg or SBP \< 90 mmHg), or oxygen saturation (without oxygen) \< 94%; 4. Patients with high risk of respiratory depression or respiratory depression (such as sleep apnea syndrome); 5. Patients who are allergic to the test drugs (dezocine, sufentanil); 6. History of bronchial asthma; 7. Patients with hypothyroidism; 8. Patients with uncontrolled gastrointestinal ulcers, gastrointestinal bleeding or perforation before surgery; or patients with paralytic ileus; 9. Patients with chronic (continuous 3 months or intermittent up to 6 months) pain associated with non-surgical sites; 10. Craniocerebral injury, possible intracranial hypertension, cerebral aneurysm, cerebrovascular accident history or suffering from central nervous system diseases (such as epilepsy); 11. Suffering from mental system diseases (such as depression), or long-term use of psychotropic drugs; 12. Patients who cannot evaluate the pain intensity after surgery or are transferred to ICU; 13. Evidence of severe cardiac dysfunction (NYHA class III and IV), unstable angina pectoris or acute myocardial infarction within 6 months before enrollment; 14. Estimated operative blood loss greater than 1000 ml or other serious complications during surgery; 15. Patients with a history of drug abuse, drug abuse and alcohol abuse within 2 years before the start of the screening period; Alcohol abuse was defined as regular consumption of more than 14 drinks/week (1 drink = 150 mL wine or 360 mL beer or 45 mL spirits); 16. Patients who have been taking opioids for a long time (continuous use for 1 month or intermittent use for up to 3 months), or who are tolerant to opioids; 17. Patients who have used monoamine oxidase inhibitors within 2 weeks; 18. Participating in any clinical trial as a subject within 3 months; 19. Pregnant or lactating women or patients with fertility plan within 6 months (including men); 20. Patients who are judged unsuitable for participation by other investigators.