‘SERUM LACTATE AND CALCIUM AS POSSIBLE OUTCOME PREDICTORS IN SEVERE TRAUMATIC BRAIN INJURY’

Background: Traumatic brain injury has significant morbidity and mortality. Several prognostic markers have been evaluated to predict outcomes. ABG (arterial blood gas) analyzers are routinely available and predict the value of calcium, lactate and other electrolytes. We evaluated serum calcium and lactate as a prognostic markers in severe TBI. Methods: We prospectively studied 100 patients with severe TBI. Blood samples for calcium and lactate were taken following admission, day 3 and day 7 after trauma and the relationship with mortality and functional outcome was studied. The Glasgow Outcome Scale (GOS) was used to access functional outcomes. GOS≤3 was considered a poor outcome (Group I). GOS>3 was taken as a good outcome (Group II). Results: Mean age was 51 years. Most patients were males, 77% in Group I and 70% in Group II. Patients in the GOS≤3 group were significantly older than patients with a GOS score >3(p=0.007). Lactate levels were significantly higher in the GOS≤3 group on day 3 (p<0.0001) but no association on day 7. GOS and ionized calcium (P<0.0001) had a significant association on day three. There was no statistical association of GOS with non-ionized calcium. Conclusion: Raised serum lactate levels and low serum ionized calcium on day 3 correlated with poor outcomes. They can be used as prognostic markers for isolated severe TBI.