Effect of baseline cognitive impairment on association between predicted propofol effect site concentration and Bispectral index or sedation score

Abstract

Background: This study determined whether the relationship between predicted propofol effect site concentration (Ce) and observer's assessment of alertness/sedation scale (OAA/S) or Bispectral Index (BIS) was similar comparing cognitively intact vs impaired patients undergoing hip fracture repair with spinal anesthesia and sedation. Methods: Following informed consent baseline mini-mental status exam (MMSE), Clinical Dementia Rating (CDR) and geriatric depression scale (GDS) were obtained. Intraoperatively OAA/S, BIS, and propofol (timing and exact amounts) administered were recorded. Cerebrospinal fluid was collected for Alzheimer's (AD) biomarkers. Mean Ce level (AvgCe) during surgery was calculated using the area under the Ce measurement series from incision to closure, divided by surgical time. Average OAA/S (AvgOAA/S), and BIS (AvgBIS) were similarly calculated. Pearson correlations of AvgCe with AvgOAA/S and AvgBIS were calculated overall and by CDR. Nonparametric locally weighted scatterplot smoothing (LOWESS) fits of AvgOAA/S and AvgBIS on AvgCe were produced, stratified by CDR. Multivariable regression incorporating baseline cognitive measurements or AD biomarkers assessed AvgOAA/S or AvgBIS associations with AvgCe. Results: In 186 participants AvgBIS and AvgOAA/S correlated with AvgCe (Pearson ρ = − 0.72; p < 0.0001 and Pearson ρ = − 0.81; p < 0.0001, respectively), and remained unchanged across CDR levels. Association patterns of AvgOAA/S or AvgBIS on AvgCe guided by LOWESS fits and modeled through regression, were similar when stratified by CDR (p = 0.16). Multivariable modeling found no independent effect on AvgBIS or AvgOAA/S by MMSE, CDR, GDS, or AD biomarkers after accounting for AvgCe. Conclusions: When administering sedation in conjunction with spinal anesthesia, cognitive impairment does not affect the relationship between predicted propofol AvgCe and AvgOAA/S or AvgBIS.

Effects of ulinastatin combined with dexmedetomidine on cognitive dysfunction and emergence agitation in elderly patients who underwent total hip arthroplasty

“…The VAS scores of the Dex + ulinastatin group were lower than those of the ulinastatin or Dex group at 24 h after the operation, indicating that the analgesic scheme of ulinastatin combined with Dex could effectively relieve postoperative pain symptoms in elderly patients who underwent total joint replacement. The Ramsay score and OAA/S sedation score mainly reflects the sedation of patients after the operation[ 24 ]. In this study, OAA/S sedation score and Ramsay score of the Dex + ulinastatin group were significantly different from those of the Dex and ulinastatin groups on the first day after the operation, meanwhile, compared with those of the Dex and ulinastatin groups, HR and MAP of the Dex + ulinastatin group significantly reduced on the 10 min of anesthesia and 60 min of anesthesia, indicating that preemptive analgesia with ulinastatin combined with Dex could effectively reduce the postoperative stress response and improve the sedation effect.…”