Introduction: Traumatic brain injuries and intracranial bleeding are the most severe forms of traumatic injuries with a high probability of devastating prognosis. Secondary injuries of the brain, following the primary injury, are preventable, and transportation to and in the hospital; the interventions in the emergency department, operational procedures and intensive care (ICU) stay are all crucial for the prevention of the secondary insult to the injured brain. In this retrospective cohort study, we analyzed the traumatic brain injuries that were followed by the neurosurgical and intensive care departments together in ICU for the last two years. Methods: With the written permission of the hospital administration, the data in the Hospital Information System were examined. Fifty-six patients admitted to the ICU with the diagnosis of traumatic intracranial bleeding over the age of 18 were analyzed. GCS scores on admission and discharge from ICU were regarded as ≥8 (Good outcome) and <8 (Bad outcome), and patients' clinical measures were examined according to these groups. Results: Pupillary reflexes showed a statistically significant difference between the ≥8 and <8 patients on admission. Blood glucose levels were clinically higher in the GCS<8 group. On the analysis of the 17 patients whose GCS scores <8 (Bad outcome) on discharge, it was seen that 8 of them had GCS scores below 8 on admission. These patients had severe head trauma, multiple intracranial pathologies and underwent decompressive surgery besides the polytrauma of the whole body. Discussion and Conclusion: We found that patients who had polytrauma with high intracranial pressure that could not be controlled with the first-line therapies and undergoing decompressive surgery, and also the patients who had high glucose levels on admission (>200mg/dl) showed worse prognosis. Hospitals should have an algorithmic approach and periodic analysis of the performances to prevent those delicate patients from having secondary insults to the brain during the emergency interventions and after.