RESUMO
Knowledge about the influence of current neuroprotective interventions on prognostic marker after traumatic brain injury is lacking. This study aimed to evaluate the prognostic yield of estimation of serum level of protein S100B in patients with traumatic brain injury [TBI], so as to be used as prognostic marker for cases admitted to ICU after TBI. The study comprised 40 patients with TBI and 10 volunteers to donate blood as a control group. Initial injury severity was assessed at admission using the Glasgow coma score [GCS] for a total score-of 15 as the best, 13-15: mild, 9-12: moderate and GCS 0.1 micro g/L are considered pathologic. Time lag between trauma affliction and sampling [Sampling time] was identified. There were 17 patients [42.5%] with isolated TBI and 23 patients [57.5%] had TBI associated with multiple trauma. Mean initial GCS score was 11.2 +/- 2.8; range: 5-15 and 14 [35%] patients had normal cranial CT, while cranial CT was positive in 26 patients [65%]. Fifteen patients died for a mortality rate of 37.5% after a mean duration of ICU stay of 2.8+1.2 days and 25 patients were discharged after a mean ICU stay of 9.1+5.2 days. Survivors showed significantly higher GCS at time of arrival compared to non-survivors. Estimated serum levels of S 100 B were significantly higher in patients compared to control group levels, moreover, mean serum level of S 100 B was significantly [P2<0.05] higher in non-survivors compared to survivors with positive significant correlation between higher mortality and both serum levels of S 100 B, [r=0.706, P<0.001] and initial GCS, [r=0.435, P=0.005]. Using Logistic Regression analysis to identify the predictor of high mortality defined serum levels of S 100B as a significant predictor in 2 models and time of sampling in one model and Receiver operator characteristics [ROC] curve analysis judged by area under curve [AUC] defined high serum levels of S100B as the most specific predictor of mortality with an AUC=0.945, followed by sampling time with AUC 0.517. S 100 B is released into the peripheral circulation immediately after primary brain trauma. The predictive power of elevated serum S 100 B is higher than that of traditional clinical indicator. The serum S 100 B concentration reflects the severity of brain injury. So estimation of serum S100 B immediately after TBI at cutoff point of>0.1 micro g/L could be used as a predictor for post-traumatic mortality with high specificity irrespective of the extent or severity of inflicted trauma