A METABOLOMIC AND PROTEOMIC ANALYSIS OF PATHOLOGIC HYPERCOAGULABILITY IN TRAUMATIC BRAIN INJURY PATIENTS AFTER DURA VIOLATION.

BACKGROUND: The coagulopathy of traumatic brain injury (TBI) remains poorly understood. Contradictory descriptions highlight the distinction between systemic and local coagulation, with descriptions of systemic hypercoagulability despite intracranial hypocoagulopathy. This perplexing coagulation profile has been hypothesized to be due to tissue factor release. The objective of this study was to assess the coagulation profile of TBI patients undergoing neurosurgical procedures. We hypothesize that dura violation is associated with higher tissue factor and conversion to a hypercoagulable profile and unique metabolomic and proteomic phenotype.

METHODS: This is a prospective, observational cohort study of all adult TBI patients at an urban, level-1 trauma center who underwent a neurosurgical procedure from 2019 to 2021. Whole blood samples were collected before and then one hour following dura violation. Citrated rapid and tissue plasminogen activator (tPA) thrombelastography (TEG) were performed, in addition to measurement of tissue factory activity, metabolomics, and proteomics.

RESULTS: Overall, 57 patients were included. The majority (61%) were male, the median age was 52 years, 70% presented after blunt trauma, and the median Glasgow Coma Score was 7. Compared to pre-dura violation, post-dura violation blood demonstrated systemic hypercoagulability, with a significant increase in clot strength (maximum amplitude of 74.4 mm versus 63.5 mm, p < 0.0001) and a significant decrease in fibrinolysis (LY30 on tPA-challenge TEG of 1.4% versus 2.6%, p = 0.04). There were no statistically significant differences in tissue factor. Metabolomics revealed notable increases in metabolites involved in late glycolysis, cysteine and one carbon metabolites, and metabolites involved in endothelial dysfunction/arginine metabolism/responses to hypoxia. Proteomics revealed notable increase in proteins related to platelet activation and fibrinolysis inhibition.

CONCLUSION: A systemic hypercoagulability is observed in TBI patients, characterized by increased clot strength and decreased fibrinolysis and a unique metabolomic and proteomics phenotype independent of tissue factor levels.

LEVEL OF EVIDENCE: n/a (basic science).