Detection of metabolic pattern following decompressive craniectomy in severe traumatic brain injury: A microdialysis study

Objective: The aim of the study was to detect mitochondrial dysfunction and ischaemia in severe traumatic brain injury and their relationship with outcome.Methods: Forty-one patients with severe traumatic brain injury (TBI) who underwent decompressive craniectomy were prospectively monitored with intracerebral microdialysis catheters (MD). Variables related to energy metabolism were studied using microdialysis.Results: Twentysix patients (63.4%) had a good outcome in terms of Glasgow outcome score (GOS) at 6 months while the rest (15 patients) had poor GOS at 6 months. Mitochondrial dysfunction was defined as Lactate Pyruvate ratio (LP ratio) > 25 and pyruvate <70 while ischaemia was defined as LP ratio > 25 and pyruvate >70. The poor outcome group showed significantly higher proportion of mitochondrial dysfunction 65.9% vs. 55.9% (p<0.001) and ischemia 13.9% vs. 7.2% (p<0.001)Conclusions: After decompressive craniectomy in severe TBI, patients with higher incidence of mitochondrial dysfunction and ischaemia were more likely to have poorer outcome with ischaemia having a more profound effect.Abbreviations: Traumatic brain injury (TBI), microdialysis (MD), lactate pyruvate ratio (LP ratio), Glasgow coma scale (GCS), Glasgow outcome scale (GOS), cerebral perfusion pressure (CPP), intracranial pressure (ICP), mitochondrial transition pore (MTP), non-contrast computed tomography (NCCT), traumatic axonal injury (TAI).