title: The effect of preoperative suggestions on perioperative dreams and dream recalls after administration of different general anesthetic combinations: a randomized trial in maxillofacial surgery.
abstract: BACKGROUND
  Images evoked immediately before the induction of anesthesia with the help of suggestions may influence dreaming during anesthesia.The aim of the study was to assess the incidence of evoked dreams and dream recalls by employing suggestions before induction of anesthesia while administering different general anesthetic combinations.
  
  
  METHODS
  This is a single center, prospective randomized including 270 adult patients scheduled for maxillofacial surgical interventions. Patients were assigned to control, suggestion and dreamfilm groups according to the psychological method used. According to the anesthetic protocol there were also three subgroups: etomidate & sevoflurane, propofol & sevoflurane, propofol & propofol groups. Primary outcome measure was the incidence of postoperative dreams in the non-intervention group and in the three groups receiving different psychological interventions. Secondary endpoint was to test the effect of perioperative suggestions and dreamfilm-formation training on the occurrance of dreams and recallable dreams in different general anesthesiological techniques.
  
  
  RESULTS
  Dream incidence rates measured in the control group did not differ significantly (etomidate & sevoflurane: 40%, propofol & sevoflurane: 26%, propofol & propofol: 39%). A significant increase could be observed in the incidence rate of dreams between the control and suggestion groups in the propofol & sevoflurane (26%-52%) group (p = 0.023). There was a significant difference in the incidence of dreams between the control and dreamfilm subgroup in the propofol & sevoflurane (26% vs. 57%), and in the propofol & propofol group (39% vs.70%) (p = 0.010, and p = 0.009, respectively). Similar to this, there was a significant difference in dream incidence between the dreamfilm and the suggestion subgroups (44% vs. 70%) in the propofol & propofol group (p = 0.019). Propofol as an induction agent contributed most to dream formation and recalls (χ2-test p value: 0.005). The content of images and dreams evoked using suggestions showed great agreement using all three anesthetic protocols.
  
  
  CONCLUSIONS
  The psychological method influenced dreaming during anesthesia. The increase of the incidence rate of dreams was dependent on the anesthetic agent used, especially the induction agent. The study was registered in ClinicalTrials.gov. Identifier: NCT01839201.
authors: Department of Anesthesiology and Intensive Care, Medical and Health Science Centre, University of Debrecen, Debrecen, Hungary.
authors: Judit
authors: J
authors: Gyulaházi
authors: Department of Affective Psychology, Institute of Psychology, Eötvös Loránd University, Budapest, Hungary.
authors: Katalin
authors: K
authors: Varga
authors: Department of Applied Mathematics and Probability Theory, Faculty of Informatics, University of Debrecen, Debrecen, Hungary.
authors: Endre
authors: E
authors: Iglói
authors: Department of Oral and Maxillofacial Surgery of the University of Debrecen, Debrecen, Hungary.
authors: Pál
authors: P
authors: Redl
authors: Department of Economic Analysis and Business Informatics, Faculty of Economics and Business Administration, University of Debrecen, Debrecen, Hungary.
authors: János
authors: J
authors: Kormos
authors: Department of Anesthesiology and Intensive Care, Medical and Health Science Centre, University of Debrecen, Debrecen, Hungary.
authors: Béla
authors: B
authors: Fülesdi
mesh_terms: D000328:Adult; D000368:Aged; D018681:Anesthetics, General / Q000494:pharmacology*; D004325:Dreams / Q000187:drug effects* / Q000523:psychology*; D005045:Etomidate / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000187:drug effects*; D008738:Methyl Ethers / Q000494:pharmacology; D008875:Middle Aged; D015742:Propofol / Q000494:pharmacology; D000077149:Sevoflurane; D013404:Suggestion; D013515:Surgery, Oral / Q000523:psychology*; D055815:Young Adult
chemical_list: D018681:Anesthetics, General; D008738:Methyl Ethers; D000077149:Sevoflurane; D015742:Propofol; D005045:Etomidate