Predictors of recovery in moderate to severe traumatic brain injury

J Neurosurg. 2018 Nov 1:1-10. doi: 10.3171/2018.4.JNS172185. Online ahead of print.

Abstract

OBJECTIVETraumatic brain injury (TBI) is a significant cause of morbidity and mortality worldwide. Clinical outcomes in TBI are determined by the severity of injury, which is dependent on the primary and secondary brain injury processes. Whereas primary brain injury lesions are related to the site of impact, secondary brain injury results from physiological changes caused by oxidative stress and inflammatory responses that occur after the primary insult. The aim of this study was to identify important clinical and biomarker profiles that were predictive of recovery after moderate to severe TBI. A good functional outcome was defined as a Glasgow Outcome Scale (GOS) score of ≥ 4.METHODSThis was a prospective study of patients with moderate to severe TBI managed at the Nelson Mandela Academic Hospital during the period between March 2014 and March 2016. Following admission and initial management, the patient demographic data (sex, age) and admission Glasgow Coma Scale score were recorded. Oxidative stress and inflammatory biomarkers in blood and CSF were sampled on days 1-7. On day 14, only blood was sampled for the same biomarkers. The primary outcome was the GOS score-due to its simplicity, the GOS was used to assess clinical outcomes at day 90. Because of difficulty in performing regular follow-up due to the vastness of the region, difficult terrain, and long travel distances, a 3-month follow-up period was used to avoid default.RESULTSSixty-four patients with Glasgow Coma Scale scores of ≤ 12 were seen and managed. Among the 56 patients who survived, 42 showed significant recovery (GOS score ≥ 4) at 3 months. Important predictors of recovery included antioxidant activity in the CSF (superoxide dismutase and total antioxidant capacity).CONCLUSIONSRecovery after TBI was dependent on the resolution of oxidative stress imbalance.

Keywords: AUC = area under the curve; BBB = blood-brain barrier; CI = confidence interval; GCS = Glasgow Coma Scale; GOS = Glasgow Outcome Scale; HR = hazard ratio; ICP = intracranial pressure; IL = interleukin; MDA = malondialdehyde; PBO2 = brain tissue oxygen tension; ROC = receiver operating characteristic; SOD = superoxide dismutase; TAC = total antioxidant capacity; TBARS = thiobarbituric acid reactive substances; TBI = traumatic brain injury; TNFα = tumor necrosis factor–α; inflammatory changes; oxidative stress; recovery; trauma; traumatic brain injury.