title: Plasma Potassium Concentration on Admission Correlates with Neurologic Outcome in Traumatic Brain Injury Patients Treated with Targeted Temperature Management: A Post Hoc Analysis of a Multicenter Randomized Controlled Trial.
abstract: BACKGROUND
  Recent studies have focused on the association between plasma electrolytes, particularly potassium level and neurologic outcomes in patients with traumatic brain injury (TBI). We hypothesized that potassium level on admission is an indicator for initiation of targeted temperature management in patients with severe TBI.
  
  
  METHODS
  We re-evaluated the Brain Hypothermia Study data based on the potassium levels on admission (i.e., hypokalemia [<3.5 mEq/L] or normokalemia [3.5-5 mEq/L]) and compared these values and Glasgow Outcome Scale scores at 6 months by per protocol analysis. Consequently, 135 patients were enrolled. Finally, groups 50 and 23 patients with hypokalemia and 34 and 23 patients with normokalemia were allocated to mild therapeutic hypothermia (MTH) and fever control groups, respectively. Baseline characteristics, complication rates, and favorable neurologic outcome rates were compared between the two groups.
  
  
  RESULTS
  In the normokalemia patients, fever control management was associated with a significant increase in favorable neurologic outcome compared with those in the MTH group (68.2% vs. 35.3%; P = 0.03). The complication rate was significantly higher in the MTH group than in the fever control group for patients with normokalemia (23.4% vs. 0%; P = 0.03). Conversely, hypokalemia patients in the MTH group revealed relatively better favorable neurologic outcomes compared with those in the fever control group (52.0% vs. 39.1%; P = 0.33).
  
  
  CONCLUSIONS
  The initial potassium level may be an indicator in determining appropriate targeted temperature management for patients with TBI. Fever control may be considered instead of MTH for normokalemia patients with TBI on admission.
authors.affiliation: Department of Emergency, Disaster and Critical Care Medicine, Kagawa University Hospital, Kagawa, Japan. Electronic address: hifumitoru@gmail.com.
authors.forename: Toru
authors.initials: T
authors.lastname: Hifumi
authors.affiliation: Department of Emergency, Disaster and Critical Care Medicine, Kagawa University Hospital, Kagawa, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kuroda
authors.affiliation: Department of Emergency, Disaster and Critical Care Medicine, Kagawa University Hospital, Kagawa, Japan.
authors.forename: Kenya
authors.initials: K
authors.lastname: Kawakita
authors.affiliation: Department of Emergency Medicine, Tokuyama Central Hospital, Yamaguchi, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Yamashita
authors.affiliation: Advanced Medical Emergency and Critical Care Center, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Oda
authors.affiliation: Department of Emergency Medicine, School of Medicine, Jikei University, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Dohi
authors.affiliation: Yamaguchi Prefectural Grand Medical Center, Yamaguchi, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Maekawa
mesh_terms: D015415:Biomarkers / Q000097:blood; D000070642:Brain Injuries, Traumatic / Q000097:blood* / Q000453:epidemiology / Q000628:therapy*; D015984:Causality; D015897:Comorbidity; D005260:Female; D006801:Humans; D006979:Hyperthermia, Induced; D007008:Hypokalemia / Q000097:blood* / Q000453:epidemiology / Q000517:prevention & control; D007036:Hypothermia, Induced; D007564:Japan / Q000453:epidemiology; D008297:Male; D009422:Nervous System Diseases / Q000097:blood* / Q000453:epidemiology / Q000517:prevention & control*; D010343:Patient Admission; D011188:Potassium / Q000097:blood*; D011379:Prognosis; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D011188:Potassium
keywords: Heterogeneous pathophysiology; Multicenter randomized controlled trial; Potassium; Therapeutic hypothermia; Traumatic brain injury