The influence of initial target effect-site concentrations of propofol on the similarity of effect-sites concentrations at loss and return of consciousness in elderly female patients with the Diprifusor system

Abstract

Background:Whether effect-site concentrations of propofol (Cep) at loss of consciousness and return of consciousness (LOC and ROC, respectively) in elderly women using Diprifusor are similar is unclear. We investigated whether differences in initial target Cep (Ctarget) alter similarities between Cep values at LOC and ROC.Materials and Methods:In this study, female patients (n = 58, age = 72.5 ± 1.1 years) undergoing knee arthroplasty were administered propofol with Diprifusor. Cep at LOC and ROC were estimated for different Ctarget values (3.0–4.5 μg/ml). Pearson's correlation coefficient analysis and simple regression were performed to assess the relationship between Cep at LOC and ROC for each Ctarget. Differences in correlation coefficients of regression lines obtained from each Ctarget group were determined using the t-test.Results:The different Ctarget groups did not show significant differences in total propofol levels and in Cep values at LOC or ROC. However, Cep at ROC was significantly higher than Cep at LOC when Ctarget was 4.0 and 4.5 μg/ml, whereas these Cep values were not significantly different in low Ctarget groups.Strong positive correlations were observed between Cep at LOC and ROC for all Ctarget groups. Regression coefficients for the different Ctarget groups were not significantly different. Compared to low (≤3.5 μg/ml) Ctarget groups, high Ctarget groups showed significantly shorter time until LOC. Induction quality was not significantly different among the groups.Conclusions:In elderly women, Cep values at LOC are strong predictors of Cep at ROC when Ctarget is 3.0–4.5 μg/ml. High Ctarget groups (≥4.0 μg/ml) exhibited shorter induction times with normal cardiovascular stability.

Effect site concentration of propofol at induction and recovery of anaesthesia - A correlative dose-response study

“…Shibuta et al . [ 11 ] reported that in female patients the Ce at ROC was higher than that at LOC. They defined LOC and ROC based on response to a physical stimulus rather than a verbal command.…”

“…Many studies have reported a positive correlation between Ce IND and Ce REC. [ 11 12 22 ] Koo et al . [ 12 ] observed a Ce LOC of 4.4 ± 1.1 μg/ml and Ce ROC of 1.1 ± 0.3 μg/ml and correlation coefficient of 0.23 using Schnider model.…”

“…Assuming power as 90%, alpha error as 5% and standard deviation (SD) based on previous studies,[ 11 12 ] the sample size was calculated as 90. The statistical software, namely SPSS version 23.0 (Statistical Package for the Social Sciences, IBM, New York, US, 2015) was used for the analysis of the data.…”

Effect of preconditioning on propofol-induced neurotoxicity during the developmental period

“…Propofol (PPF), whose chemical structure is shown in Fig 1, is one of the most extensively used intravenous anesthetic agents in clinical settings, especially in pediatric and obstetric patients, because of its rapid onset and reversibility. However, PPF-associated neurotoxicity at the developmental stages remains a concern [1]. Moreover, because PPF crosses the placenta, caution should be exercised when administering it to pregnant women.…”