Abstract
BACKGROUND: Ciprofol, a novel intravenous anesthetic for procedural sedation and general anesthesia, characterized by rapid onset of action, lower rates of injection pain and effective sedation at lower doses, is a promising alternative to propofol. Further clinical evidence is needed on how to adjust the dosage regimen of ciprofol during anesthesia induction in elderly patients. This study aims to provide evidence-based dosing reference and investigate the correlation between patient age and the ciprofol requirement for loss of consciousness (LOC) during anesthesia induction. METHODS: A total of 102 patients scheduled for elective surgery under general anesthesia were enrolled and grouped to Group A (51 patients, 18-64 years) and Group B (51 patients, ≥65 years) according to their age. All subjects received ciprofol (at a rate of 5 mg/kg/min) alone for inducing LOC, which was defined as loss of eyelash reflex and Modified Observer's Alertness/Sedation (MOAA/S) score of 1 or less. The dose of ciprofol and the time to loss of eyelash reflex for each subject were recorded. RESULTS: Compared with patients in group A, patients in group B had a mean reduction in ciprofol requirement of 0.07 mg/kg and a mean reduction in the time to loss of eyelash reflex of 55.20 s. Bivariate linear correlation analysis showed that ciprofol requirement for LOC was significantly and positively correlated with albumin (r = 0.359; 95% CI = 0.177-0.518; p < 0.001), and negatively correlated with age, such that significant decline in ciprofol requirement with increasing age (r = -0.516; 95% CI = -0.645--0.357; p < 0.001). Multivariable linear regression models were employed to assess the independent association between age and ciprofol requirement for LOC. After controlling for potential confounding variables, age remained a significant independent predictor of ciprofol requirement. CONCLUSION: The ciprofol requirement for LOC was significantly reduced in elderly patients. Our findings demonstrated that age serves as an independent factor influencing the ciprofol requirement for LOC during general anesthesia induction. These results suggest that the induction dose of ciprofol should be further reduced in elderly surgical patients, particularly those aged 75 years or older. CLINICAL TRIAL REGISTRATION: https://www.chictr.org.cn/; Identifier: ChiCTR2400093112.