The prevalence of sodium abnormalities in moderate to severe traumatic brain injury patients in a level 1 Trauma unit in Durban

Abstract

Background: The prevalence of sodium abnormalities in the moderate to severe brain injury patient is not known in the South African population.

Objectives: Determine the prevalence of sodium abnormalities in moderate to severe traumatic brain injury. Determine Glasgow Outcome Score (GOS) between sodium groups.

Methods: Patients admitted to the trauma intensive care unit between January 2013 and June 2015 with moderate to severe traumatic brain injury were  included in the study. Descriptive statistics, tests of association and tests of differences were used.

Results: There were 184 patients with 143 (77.7%) males and 41 (22.3%) females. Abnormal sodium was present in 126 (68.4%), 61 of whom had  hyponatremia and 65 hypernatremia, a prevalence of 33.1% and 35.3% respectively. Of the 65 patients with hypernatremia, 52 (80%) had dehydration, 7  (10.7%) had diabetes insipidus (DI) and 6 (9.3%) had hyperosmolar therapy as the cause. Of the 61 patients with hyponatremia, the commonest cause was  fluid overload in 47 patients (77.1%) with SIADH in 11 (18%) and CSWS in 3 (4.9%). Death occurred in 34 (18.5%) patients and diagnosis was found to  be significantly associated with mortality (p = 0.01), the most common diagnoses amongst those who died being dehydration (29.4%), fluid overload  (17.7%) and DI (14.7%).

Conclusions: The prevalence of sodium abnormalities was 126 (68.4%) patients of whom 61 (33.1%) had hyponatremia and 65 (35.3%) hypernatremia. In  those patients who survived, a later onset was related to a better outcome. The GOS in DI tended to be worse.