title: Postoperative cognitive changes after total knee arthroplasty under regional anesthesia.
abstract: BACKGROUND
  The type of postoperative cognitive decline after surgery under spinal anesthesia is unknown. We investigated the type of postoperative cognitive decline after total knee arthroplasty (TKA). Neuropsychological testing was conducted and the changes in cerebrospinal fluid (CSF) biomarkers after surgery were evaluated.
  
  
  METHODS
  Fifteen patients who required bilateral TKA at a 1-week interval under spinal anesthesia were included. Neuropsychological tests were performed twice, once the day before the first operation and just before the second operation (usually 1 week after the first test) to determine cognitive decline. Validated neuropsychological tests were used to examine 4 types of cognitive decline: memory, frontal-executive, language-semantic, and others. Concentrations of CSF amyloid peptide, tau protein, and S100B were measured twice during spinal anesthesia at a 1-week interval. The patients showed poor performance in frontal-executive function (forward digit span, semantic fluency, letter-phonemic fluency, and Stroop color reading) at the second compared to the first neuropsychological assessment.
  
  
  RESULTS
  S100B concentration decreased significantly 1 week after the operation compared to the basal value (638 ± 178 vs 509 ± 167 pg/mL) (P = 0.019). Amyloid protein β1-42, total tau, and phosphorylated tau concentrations tended to decrease but the changes were not significant.
  
  
  CONCLUSIONS
  Our results suggest that frontal-executive function declined 1 week after TKA under spinal anesthesia. The CSF biomarker analysis indicated that TKA under regional anesthesia might not cause neuronal damage.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam Department of Anesthesiology and Pain Medicine, Inha University School of Medicine, Inha University Hospital Department of Neurology, Seoul National University College of Medicine, Seoul Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam College of BioNano technology, Gacheon University, South Korea.
authors.forename: Young-Tae
authors.initials: YT
authors.lastname: Jeon
authors.forename: Byung-Gun
authors.initials: BG
authors.lastname: Kim
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Park
authors.forename: Hye-Min
authors.initials: HM
authors.lastname: Sohn
authors.forename: Jungeun
authors.initials: J
authors.lastname: Kim
authors.forename: Seung Chan
authors.initials: SC
authors.lastname: Kim
authors.forename: Seong Soo
authors.initials: SS
authors.lastname: An
authors.forename: SangYun
authors.initials: S
authors.lastname: Kim
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid; D000775:Anesthesia, Spinal / Q000009:adverse effects*; D000779:Anesthetics, Local; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D002045:Bupivacaine; D060825:Cognitive Dysfunction / Q000134:cerebrospinal fluid* / Q000209:etiology; D056344:Executive Function; D006801:Humans; D009483:Neuropsychological Tests; D010446:Peptide Fragments / Q000134:cerebrospinal fluid; D010766:Phosphorylation; D011183:Postoperative Complications / Q000134:cerebrospinal fluid* / Q000209:etiology; D064568:S100 Calcium Binding Protein beta Subunit / Q000134:cerebrospinal fluid; D013997:Time Factors; D016875:tau Proteins / Q000134:cerebrospinal fluid / Q000378:metabolism
chemical_list: D016229:Amyloid beta-Peptides; D000779:Anesthetics, Local; D010446:Peptide Fragments; D064568:S100 Calcium Binding Protein beta Subunit; C579160:S100B protein, human; C075222:amyloid beta-protein (1-42); D016875:tau Proteins; D002045:Bupivacaine