the 95% Effective Dose of Ciprofol for Adjunctive Sedation Undergoing Knee Arthroplasty in Elderly People
Regional anesthesia is a common clinical anesthesia method, and regional anesthesia-assisted sedation play a central role in promoting patient comfort and relieving anxiety. With increasing age, elderly people experience changes in pharmacokinetics and pharmacodynamics and increased drug sensitivity. Ciprofol has advantages in adverse events such as hypotension and respiratory depression. There are fewer studies on the recommended dosage of ciprofol-assisted sedation for intrathecal anesthesia in elderly patients. The aim of study is to identify the 95% effective dose of ciprofol-assisted sedation in elderly patients undergoing spinal anesthesia using a biased coin design up-and-down sequential method(BCD-UDM)
- EligibilityCriteria: Inclusion Criteria:  Age ≥ 65 years ASA grade I~III BMI 18~28 kg/m2  Exclusion Criteria:  Contraindications to intrathecal anesthesia Suffering from severe psychiatric or neurologic disorders or taking sedative drugs within the last 3 months Difficult airway or having respiratory diseases such as upper airway obstruction Severe cardiovascular system diseases Severe hepatic or renal dysfunction Allergy or contraindication to propofol and its drug-related components Patient Prefusal - HealthyVolunteers: No - Gender: All - MinimumAge: 65 Years - StdAgeList: Older Adult