Is hypernatremia a risk factor to expansive hematomas among traumatic brain injured patients in a tertiary Sub-Saharan hospital?

Background: Hypernatremia is a common electrolyte imbalance observed in patients with traumatic brain injury (TBI) and it commonly leads to poor outcome. However, the consequence of hypernatremia on occurrence of expansive hematoma (EH) is not well established, though there is limited information on the burden of EH among TBI patients and associated risk factors. This study therefore assessed the proportion of hypernatremia and its correlation with EH among TBI patients at Mulago National Referral Hospital (MNRH), Kampala, Uganda. Methods: : A prospective cohort study was conducted among TBI patients with intracranial hematoma undergoing surgical evacuation during a period of 16 th June 2021 to 17 th June 2022. A total of 332 patients were prospectively recruited. Demographic, clinical, laboratory and radiological data were captured using the Research Electronic Data Capture (Redcap) system. Patients were monitored for hematoma enlargement complications. The independent outcome was the sodium level (Na) > 145. The dependent outcomes were hematoma enlargement of over 33% evidence by two CT scans (baseline and follow up). Univariate and multivariate analyses were used to identify variables associated with hematoma enlargement. Results: : 184 participants (55.4%) had expansive hematomas identified on CT scan resulting in a proportion of 0.55 95% CI (0.50 to 0.60). Hypernatremia was detected in 80 patients (25.2 %) within 24 hours of admission. At multivariate analyses, the results showed that only hypernatremia PR =1.56 (95% CI 1.17 to 2.10; P=0.003) was found to be a risk factor for expansive hematomas among patients with TBI. Conclusion: Hypernatremia is common with a prevalence of 25.2.8% among TBI patients. Patients with hypernatremia have 1.56-times higher risk of developing a EH when compared to patients who had no hypernatremia. These findings imply routine plasma sodium levels monitoring and could form the basis for establishing a blood chemistry control protocol for such patients in remote settings.