predictive factors of survival and 6-month favorable outcome of very severe head trauma patients; a historical cohort study

introduction : very severe head trauma cases, defined as glasgow coma scale (gcs) scores of less than 6, have a higher mortality rate and poorer outcome. the purpose of this study was to recognize factors associated with survival and 6-month favorable outcome of very severe head trauma patients presenting to emergency department.  methods: in this historical cohort study, the authors retrospectively reviewed medical records of head trauma patients who were admitted to the emergency department with post-resuscitation gcs scores of less than 6. both univariate and multivariate analyses were used to test the association between various parameters with survival and 6-month outcome.  results: 103 cases with the mean age of 39 ± 16.5 years were studied (80% male). the overall survival rate was 41.7% and the rate of 6-month favorable outcome was 28.2%. in multivariate analysis, brisk pupil light reaction on admission and patent basal cistern on brain computed tomography (ct) scan were significant factors associated with both survival (or 5.20, 95% ci 1.57-17.246, p = 0.007 and or 3.65, 95% ci 1.22-10.91, p=0.02 respectively) and favorable outcome (or 4.07, 95% ci 1.35-12.24, p=0.01 and or 3.54, 95% ci 1.22-10.26, p 0.02), respectively.  conclusion: based on the results of present study, the survival rate of patients with very severe head trauma (gcs < 6) was 41.7%. the strong predictors of survival and 6-month favorable outcome of these patients were brisk pupillary reactivity and patent cistern on brain ct scan. it seems that very severe head trauma patients still have a reasonable chance to survive and aggressive management should be continued.