(AS1) Revising the Brain Injury Guidelines: Grading of Traumatic Subarachnoid Hemorrhage in Patients with Impaired Coagulation Does Not Predict Outcomes

Introduction: Low-risk traumatic brain injury (TBI) management remains open for optimization of value and quality. Risk-stratification systems like the Brain Injury Guidelines (BIG) are used guide triage and early management. The BIG were independently validated and implemented at our institution (Oregon Health & Science University) in 2016 after creation of a prospective institutional TBI database to evaluate outcomes.
A weakness of BIG is the subjective grading of traumatic subarachnoid hemorrhage (tSAH) into “trace,” “localized”, or “scattered” severity. This, in addition to studies showing the low risk of progression or deterioration with tSAH even in the presence of anticoagulant or antiplatelet use, merits re-evaluation of the scheme by which tSAH is risk-stratified. The purpose of this study is to evaluate whether the BIG tSAH grading scheme confers any additional diagnostic utility in the risk-stratification of TBI with impaired coagulation.

Methods: This is a retrospective analysis of prospectively collected TBI admissions at a single institution from 2013-2020. Patients with isolated tSAH in the setting of antiplatelet/anticoagulant therapy were queried. Outcomes included radiographic progression of tSAH, neurological deterioration, and need for neurosurgical intervention.

Results: Analysis included 125 patients. Fifty-five (44%) had trace, 31 (24.8%) localized, and 39 (31.2%) scattered tSAH. Only 11 (8.8%) patients experienced radiographic progression. Five (4%) patients suffered a neurological deterioration. One patient had neurosurgical intervention, a decompressive craniectomy, within 24 hours of admission. There were 3 deaths; 2 were due to unexpected non-neurological events and the third was due to withdrawal of care after radiographic progression and neurological decline. Grade of tSAH did not predict any of the outcomes (P > 0.05).

Conclusion : The subset of patients with isolated tSAH on anticoagulation/antiplatelet therapy experience very low rates of radiographic or clinical worsening, regardless of hemorrhage severity. Grading of tSAH did not predict outcome.