title: Awareness during anesthesia: the results of a questionnaire survey in Japan.
abstract: OBJECTIVE
  We planned a survey to evaluate the current incidence and risk factors of intraoperative awareness.
  
  
  METHODS
  A questionnaire survey was conducted via the Internet. The survey was designed to obtain information regarding cases involving intraoperative awareness in 2008.
  
  
  RESULTS
  A total of 172 anesthesiologists answered the survey. The total number of reported anesthetic cases was 85,156. Twenty-four cases of definite or possible awareness were reported by 21 anesthesiologists, of which 14 were cases of definite awareness and ten of possible awareness. The incidence of awareness, including possible awareness, was 0.028%. Propofol was used in 21 cases, sevoflurane in two, and a high dose of fentanyl in one. Bispectral index (BIS) monitoring was used in seven cases (29%). Sixteen patients (67%) were <50 years old, six (26%) were men, and 17 (74%) were women. As the type of surgery, three cases (13%) involved gynecological surgeries and seven (30%) involved cervicofacial surgeries. During surgery, the memory at postural change was preserved in two cases.
  
  
  CONCLUSIONS
  The most surprising finding of this study is that total intravenous anesthesia (TIVA) was used in 21 of the 24 (88%) cases of definite and possible awareness. Although the incidence of intraoperative awareness was compatible with the previous studies, meticulous care should be taken when anesthesia is performed by TIVA for high-risk patients. The results of this survey should be verified, as well as further continuous survey and prospective study, because this study was performed by an anonymous questionnaire survey conducted over only 1-year period.
authors.affiliation: Department of Anesthesia, Ube Industries Central Hospital, 750 Nishikiwa, Ube 755-0151, Japan. yamorimo@nifty.com
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Morimoto
authors.forename: Yuko
authors.initials: Y
authors.lastname: Nogami
authors.forename: Kaori
authors.initials: K
authors.lastname: Harada
authors.forename: Tsunehisa
authors.initials: T
authors.lastname: Tsubokawa
authors.forename: Kenichi
authors.initials: K
authors.lastname: Masui
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000768:Anesthesia, General / Q000706:statistics & numerical data; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D018686:Anesthetics, Intravenous; D056805:Consciousness Monitors; D005260:Female; D019538:Health Care Surveys; D006801:Humans; D058926:Intraoperative Awareness / Q000453:epidemiology* / Q000523:psychology; D007564:Japan / Q000453:epidemiology; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage; D008875:Middle Aged; D010880:Piperidines; D000077208:Remifentanil; D012307:Risk Factors; D000077149:Sevoflurane; D013514:Surgical Procedures, Operative / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D008738:Methyl Ethers; D010880:Piperidines; D000077149:Sevoflurane; D000077208:Remifentanil