Hypomagnesemia as a possible marker of disability in patients with severe traumatic brain injury.

Background: To find association between hydroelectrolyte disbalance and disability in patients with severe traumatic brain injury using the Glasgow Outcome Scale (GOS) for classification. Method: This is a retrospective cohort study based on 83 clinical charts of inpatients with severe traumatic brain injury (TBI) and a Glasgow Coma Scale score lower than 8, covering a three-year period. Data from the clinical charts aim to establish a relationship between GOS results and electrolyte levels analysis six months after initial trauma. Bivariate analysis and chi square 95% reliability rate, were applied to categorical variables. One-way ANOVA, for independent groups, was used to determine association between different levels of individual electrolytes (Na+, K+, Ca++, Mg++ and Cl-) and disability. The statistical analysis for continuous variables comparison was made by chi square test. Multivariate Logistic Regression analysis was useful to determine association. Results: Disability was statistically associated with the increment of age (p=<0,01), higher APACHE II score, (Acute Physiology and Chronic Health Evaluation) prolonged mechanic ventilation use, hypomagnesemia and hyperkalemia. Conclusions: Hypomagnesemia and hyperkalemia could be associated with higher disability according to measurement of GOS.