(1547) The Role of Prehospital Antiplatelet Use and Thromboelastography in Traumatic Brain Injury Patients

Introduction: The brain injury guidelines (BIG) offer valuable criteria for identifying trauma patients who require observation without immediate intervention. One variable evaluated in BIG is prehospital use of aspirin (ASA) or clopidogrel; these patients are classified BIG3 requiring repeat head computed tomography (CT) and neurosurgery consultation. This study aims to investigate the rate of hemorrhage progression and neurosurgery intervention (NSI) in patients fulfilling all BIG1 criteria except prehospital ASA or clopidogrel use. Additionally, we explored the potential of thromboelastography (TEG) with platelet mapping (PM) to identify patients whose platelets remain uninhibited by prehospital antiplatelet therapy, suggesting they could be safely managed the same as BIG1 patients.

Methods: Retrospective review of trauma registry data at a Level I trauma center between January 2017 and March 2022 focused on traumatic brain injury (TBI) patients who reported prehospital ASA or clopidogrel use. Patients were categorized BIG 1, 2, or 3 based on the initial CT scan, GCS admission score, intoxication, skull fracture type, and presence and size of intracranial hemorrhages. The impact of antiplatelet agents on platelet function was analyzed using TEG with PM.

Results: We identified 236 blunt TBI patients on prehospital ASA or clopidogrel. Admission GCS scores were: 3-8 (6.4%), 9-12 (1.7%), and 13-15 (91.9%). BIG scores, excluding antiplatelet medications, resulted in BIG1 (24.6%), BIG2 (19.5%), and BIG3 (55.9%) classifications. 32% of patients on prehospital clopidogrel showed adenosine diphosphate inhibition greater than 60%, while 61% of those on prehospital ASA had arachidonic acid inhibition greater than 60%. Of the 58 cases fulfilling BIG1 criteria in all parameters except prehospital ASA or clopidogrel use, all but one patient demonstrated a stable repeat head CT, and no NSI was required.

Conclusions: Prehospital ASA or clopidogrel use did not significantly impact hemorrhage progression or the need for NSI in blunt TBI patients otherwise meeting BIG1 criteria. Further, TEG with PM provided valuable insights into platelet inhibition levels. These findings indicate the benefits of tailoring management strategies for trauma patients on antiplatelet therapy to optimize resource allocation and improve care.