title: Characteristics of regional cerebral oxygen saturation levels in patients with out-of-hospital cardiac arrest with or without return of spontaneous circulation: A prospective observational multicentre study.
abstract: OBJECTIVE
  Our study aimed at filling the fundamental knowledge gap on the characteristics of regional brain oxygen saturation (rSO2) levels in out-of-hospital cardiac arrest (OHCA) patients with or without return of spontaneous circulation (ROSC) upon arrival at the hospital for estimating the quality of cardiopulmonary resuscitation and neurological prognostication in these patients.
  
  
  METHODS
  We enrolled 1921 OHCA patients from the Japan - Prediction of Neurological Outcomes in Patients Post-cardiac Arrest Registry and measured their rSO2 immediately upon arrival at the hospital by near-infrared spectroscopy using two independent forehead probes (right and left). We also assessed the percentage of patients with a good neurological outcome (defined as cerebral performance categories 1 or 2) 90 days post cardiac arrest.
  
  
  RESULTS
  After 90 days, 79 (4%) patients had good neurological outcomes and a median lower rSO2 level of 15% (15-20%). Compared to patients without ROSC upon arrival at the hospital, those with ROSC had significantly higher rSO2 levels (56% [39-65%] vs. 15% [15-17%], respectively; P<0.01), and significantly correlated right- and left-sided regional brain oxygen saturation levels (R=0.94 vs. 0.66, respectively). In both groups, the percentage of patients with a good 90-day neurological outcome increased significantly in proportion to their rSO2 levels upon arrival at the hospital (P<0.01).
  
  
  CONCLUSIONS
  Our data indicate that measuring rSO2 levels might be effective for both monitoring the quality of resuscitation and neurological prognostication in patients with OHCA.
authors.affiliation: Department of Primary Care and Emergency Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan. Electronic address: keinishi@kuhp.kyoto-u.ac.jp.
authors.forename: Kei
authors.initials: K
authors.lastname: Nishiyama
authors.affiliation: Department of Cardiovascular Medicine, Kawasaki Saiwai Hospital, Kawasaki, Japan.
authors.forename: Noritoshi
authors.initials: N
authors.lastname: Ito
authors.affiliation: Department of Emergency and Critical Care Medicine, Saiseikai Yokohamashi Tobu Hospital, Yokohama, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Orita
authors.affiliation: Emergency and Critical Care Medicine, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Hayashida
authors.affiliation: Department of Emergency and Critical Care Medical Center, Osaka City General Hospital, Osaka, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Arimoto
authors.affiliation: Department of Cardiology, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Abe
authors.affiliation: Department of Cardiology, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Unoki
authors.affiliation: Advanced Emergency Center, Tohoku University Hospital, Sendai, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Endo
authors.affiliation: Department of Emergency and Critical Care Medicine, Fukuoka University Hospital, Fukuoka, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Murai
authors.affiliation: Critical Care Center, Mie University Hospital, Tsu, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Ishikura
authors.affiliation: Advanced Critical Care Center, Gifu University Hospital, Gifu, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Yamada
authors.affiliation: Department of Cardiology, Kyoto Katsura Hospital, Kyoto, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Mizobuchi
authors.affiliation: Department of Cardiology, Fujisawa City Hospital, Fujisawa, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Anan
authors.affiliation: Advanced Critical Care Center, Nara Medical University Hospital, Kashihara, Japan.
authors.forename: Tomorou
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Emergency and Critical Care Medicine, Japanese Red Cross Musashino Hospital, Musashino, Japan.
authors.forename: Hideto
authors.initials: H
authors.lastname: Yasuda
authors.affiliation: Department of Emergency and Critical Care Medicine, St. Luke's International Hospital, Tokyo, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Homma
authors.affiliation: Emergency and Critical Care Medicine, Seirei Hamamatsu General Hospital, Hamamatsu, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Shiga
authors.affiliation: Department of Cardiovascular Medicine, Dokkyo Medical University, Tochigi, Japan.
authors.forename: Michiaki
authors.initials: M
authors.lastname: Tokura
authors.affiliation: Department of Health Informatics, Kyoto University School of Public Health, Kyoto, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Tsujimura
authors.affiliation: Emergency Life Saving Technique Academy, Fukuoka, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Hatanaka
authors.affiliation: Department of Cardiology, Surugadai Nihon University Hospital, Tokyo, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Nagao
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000378:metabolism*; D016887:Cardiopulmonary Resuscitation / Q000379:methods; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000378:metabolism / Q000628:therapy*; D010092:Oximetry; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology*; D011379:Prognosis; D011446:Prospective Studies; D020127:Recovery of Function / Q000502:physiology*; D019265:Spectroscopy, Near-Infrared / Q000379:methods
chemical_list: D010100:Oxygen
keywords: Cardiac arrest; Cardiopulmonary resuscitation; Cerebrovascular circulation; Near-infrared spectroscopy; Oxygen; Prognoses