title: Hypocalcemia as a prognostic factor in mortality and morbidity in moderate and severe traumatic brain injury.
abstract: OBJECTIVE
  Our main objective was to evaluate whether serum hypocalcaemia (defined as <2.1 mmol/L [8.5 mg/dL]) and ionized serum calcium (defined as <1.10 mmol/L [4.5 mg/dL]) is a prognostic factor for mortality and morbidity (defined as Glasgow outcome score [GOS] ≤3) in early moderate and severe traumatic brain injury (TBI).
  
  
  METHODS
  We developed a retrospective study and evaluated clinical profiles from included patients from January 2004 to December 2012. Patients were between 16 and 87 years old and had a Glasgow coma scale of 3-13 points following TBI, with demonstrable intracranial lesions in cranial computed tomography.
  
  
  RESULTS
  We found a significant statistical difference (P < 0.008) in the ionized serum calcium levels on the 3(rd) day of admission between the groups: GOS ≤3 and >3 (disability/death). According with the receiving operative curves analysis, we found that the best level of higher sensitivity (83.76%) and specificity (66.66%) of hypocalcaemia of serum ionized calcium on 3(rd) day was the value of 1.11 mmol/L, with an odds ratio value of 6.45 (confidence intervals 95%: 2.02-20.55).
  
  
  CONCLUSIONS
  The serum levels of ionized calcium on day 3 could be useful for the prediction of mortality and disability in patients with moderate and severe TBI.
authors.affiliation: Department of Neurosurgery, Evangelic Hospital Oldenburg, Medical Campus University of Oldenburg Germany.
authors.forename: Vinas-Rios Juan
authors.initials: VR
authors.lastname: Manuel
authors.affiliation: Department of Clinical Epidemiology, Faculty of Medicine, San Luis Potosi, Mexico.
authors.forename: Sanchez-Aguilar
authors.initials: SA
authors.lastname: Martin
authors.affiliation: Department of Neurosurgery Bathildis Krankenhaus, Bad Pyrmont, Germany.
authors.forename: Sanchez-Rodriguez Jose
authors.initials: SR
authors.lastname: Juan
authors.affiliation: Department of Clinical Epidemiology, Faculty of Medicine, San Luis Potosi, Mexico.
authors.forename: Muruato-Araiza Luis
authors.initials: MA
authors.lastname: Fernando
authors.affiliation: Department of Neurosurgery, Evangelic Hospital Oldenburg, Medical Campus University of Oldenburg Germany.
authors.forename: Meyer
authors.initials: M
authors.lastname: Frerk
authors.affiliation: Department of Neurosurgery, Evangelic Hospital Oldenburg, Medical Campus University of Oldenburg Germany.
authors.forename: Kretschmer
authors.initials: K
authors.lastname: Thomas
authors.affiliation: Department of Neurosurgery, Evangelic Hospital Oldenburg, Medical Campus University of Oldenburg Germany.
authors.forename: Heinen
authors.initials: H
authors.lastname: Christian
keywords: Glasgow outcome score; hypocalcemia; ionized serum calcium; prognostic factor; traumatic brain injury