The effect of sevoflurane on implicit memory: a double-blind, randomised study.
Forty-eight gynaecological patients were randomly allocated to three groups (target end-tidal sevoflurane concentration 1.2, 1.5 or 2%), and into subgroups for positive or neutral suggestion. Anaesthesia was induced by inhalation of sevoflurane in oxygen. When the target concentration was achieved, the bispectral index, computed from a bi-frontal electroencephalogram, was noted. One of two eight-word lists was then played to prime implicit memory, followed by a positive or neutral suggestion. After surgery, each patient tried to identify 24 words obscured by background noise. Priming increased the likelihood of identifying words in the 1.2% group only, i.e. there was evidence of implicit memory in this group. There was no evidence of a therapeutic effect of positive suggestion (p = 0.3), but the power of this part of the study was low. The bispectral index did not achieve statistical significance as an indicator of susceptibility to priming.
Renna
M
M
Department of Anaesthesia, Ealing Hospital NHS Trust, Southall, UK.
Lang
E M
EM
Lockwood
G G
GG
D000328:Adult; D000769:Anesthesia, Inhalation / Q000523:psychology; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004569:Electroencephalography / Q000187:drug effects; D005260:Female; D013509:Gynecologic Surgical Procedures; D006801:Humans; D008568:Memory / Q000187:drug effects*; D011939:Mental Recall / Q000187:drug effects; D008738:Methyl Ethers / Q000494:pharmacology*; D008875:Middle Aged; D011184:Postoperative Period; D000077149:Sevoflurane; D013404:Suggestion
D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane