title: Reduced effectiveness of hypothermia in patients lacking the wave V in auditory brainstem responses immediately following resuscitation from cardiac arrest.
abstract: OBJECTIVE
  Therapeutic hypothermia appears to improve the outcome of pre-hospital cardio-pulmonary arrest (CPA) in patients with an initial cardiac rhythm of ventricular fibrillation or nonperfusing ventricular tachycardia (VF/VT). Notwithstanding, the outcome of this procedure is certainly difficult to predict based solely on the initial rhythm. The aim of the present study was to predict the outcome using auditory brainstem responses (ABRs) in CPA patients treated with therapeutic hypothermia.
  
  
  METHODS
  A prospective observational study in the intensive care unit of a university hospital.
  
  
  METHODS
  The study included 26 patients resuscitated from out-of-hospital CPA.
  
  
  METHODS
  Basic and advanced cardiac life support, intensive care and post-resuscitative hypothermia.
  
  
  RESULTS
  ABRs were recorded immediately after the return of spontaneous circulation (ROSC). An ABR wave V was recorded in 16 patients. Among 8 patients with a favourable outcome, the initial rhythms were VF/VT in 6 patients and other rhythms in 2. All 10 patients without a detectable ABR wave V had an unfavourable outcome. The VF/VT as the initial arrest rhythm and the presence of wave V were significantly (p = 0.0095) correlated with a favourable outcome. The presence of wave V had a 100% sensitivity to a favourable outcome.
  
  
  CONCLUSIONS
  The absence of the ABR wave V in the early phase after ROSC wave indicated a reduced effect of therapeutic hypothermia, even in cases that underwent hypothermia promptly after out-of-hospital CPA. Measurement of ABRs appears to be useful as a predictor of effectiveness and as a criterion for determining the indication for therapeutic hypothermia.
authors.affiliation: Department of Emergency and Critical Care Medicine, Nihon University School of Medicine, 30-1 Oyaguchi-Kamimachi, Tokyo 173-8610, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sakurai
authors.forename: Kosaku
authors.initials: K
authors.lastname: Kinoshita
authors.forename: Takashi
authors.initials: T
authors.lastname: Moriya
authors.forename: Akira
authors.initials: A
authors.lastname: Utagawa
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ebihara
authors.forename: Makoto
authors.initials: M
authors.lastname: Furukawa
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Tanjoh
mesh_terms: D004569:Electroencephalography; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D006323:Heart Arrest / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007036:Hypothermia, Induced; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012151:Resuscitation / Q000379:methods*; D017180:Tachycardia, Ventricular / Q000503:physiopathology; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000503:physiopathology