Association of Hemoglobin Concentration with Mortality in Critically III Patients Suffering from Traumatic Brain Injury

Background and Objective: Traumatic brain injury is one of the main causes of mortality and morbidity worldwide and the second leading cause of death in Iran. About half of patients with traumatic brain injury have hemoglobin of less than 9 g/dL during the first week of admission. With regard to the secondary damage to brain tissues caused by anemia and blood transfusion complications, we decided to assess the association between hemoglobin concentration and mortality in patients with traumatic brain injury. Materials and Methods: A retrospective cohort study was conducted with patients suffering from traumatic brain injury. Demographics, physiologic data, clinical outcomes and daily hemoglobin concentrations were obtained from patients’ history records. 168 patients with traumatic brain injury were identified and 117 were included in the analysis based on inclusion/exclusion criteria. Patients were assigned to 4 groups based on their mean 7-day hemoglobin concentration. Logistic regression was used to model the association between mean daily hemoglobin concentration and hospital mortality. Results: 104 of 117 patients were male. Age, gender and days of mechanical ventilation did not show statistically significant differences among groups. Significant differences were observed in mortality rates, the number of transfused units and number of days of hospitalization among four groups. Multivariable analysis revealed that mean 7-day hemoglobin concentration < 9g/dL was independently associated with an increased risk of hospital mortality. Conclusion: A mean 7-day hemoglobin concentration of < 9g/dL is associated with increased hospital mortality in patients with traumatic brain injury.