Management of Head Trauma in Anticoagulated Patients
Obtain an immediate non-contrast head CT scan for any patient on anticoagulation who has fallen and hit their head, regardless of symptom severity or mechanism of injury. 1
Initial Imaging and Risk Assessment
The threshold for initial CT imaging in anticoagulated patients after head trauma is very low because patients on warfarin have a 3.9% risk of significant intracranial injury versus 1.5% in non-anticoagulated patients 1
Novel oral anticoagulants (NOACs) like apixaban, rivaroxaban, and dabigatran carry a lower but still elevated risk of intracranial hemorrhage (2.6%) compared to warfarin (10.2%), but both are substantially higher than patients without anticoagulation 1
Antiplatelet agents including clopidogrel carry similar bleeding risks and should not be considered safer than anticoagulants in this context 1
Aspirin monotherapy, particularly in elderly patients, carries a 4.6% risk of traumatic intracranial hemorrhage after ground-level falls, with 81.5% of these patients taking low-dose 81mg aspirin 2
Management Based on Initial CT Results
If Initial CT Shows Intracranial Hemorrhage:
Immediately discontinue the anticoagulant and consult neurosurgery 1, 3
For warfarin reversal, administer 4-factor prothrombin complex concentrate (4F-PCC) plus 5mg intravenous vitamin K to achieve INR <1.5 1
For apixaban or other factor Xa inhibitors, use andexanet alfa as the specific reversal agent if available; if unavailable, use prothrombin complex concentrate 4, 3
Consider activated charcoal if apixaban was ingested within 2-4 hours 4, 3
Obtain repeat head CT within 24 hours because anticoagulated patients have a 3-fold increased risk of hemorrhage expansion (26% versus 9% in non-anticoagulated patients) 4, 5
If Initial CT is Negative:
The patient can be safely discharged home without routine repeat imaging or hospital admission, even while on anticoagulation. 1, 4
The risk of delayed intracranial hemorrhage after a negative initial CT is very low (0.6-6%) and rarely requires neurosurgical intervention 1, 6
A multicenter study of 930 patients on warfarin or clopidogrel with negative initial CT found delayed hemorrhage in only 0.6% of warfarin patients (4 of 687) and 0% of clopidogrel patients (0 of 243), with none requiring neurosurgery 1
For patients on NOACs specifically, delayed hemorrhage occurred in only 0.95% (3 of 314 patients), with none requiring neurosurgical intervention 7
Routine repeat imaging and observation admission are NOT recommended for neurologically intact patients with negative initial CT 1, 4
Special Considerations for High-Risk Features
Brief observation (4-6 hours) before discharge may be considered for patients with:
- Age >80 years 4, 6
- History of loss of consciousness or amnesia 1, 4
- Glasgow Coma Scale <15 1, 4
- Concomitant use of multiple anticoagulant/antiplatelet agents 1, 7
Discharge Instructions
Provide clear written discharge instructions that include:
- Signs and symptoms of delayed hemorrhage (severe headache, confusion, vomiting, weakness, seizures) 1, 4
- Instructions to return immediately or call 911 if these symptoms develop 3
- Outpatient referral for fall risk assessment and reassessment of anticoagulation risk/benefit 1, 4
Common Pitfalls to Avoid
Failing to obtain initial CT imaging in anticoagulated patients after any head trauma, even with minor mechanisms like ground-level falls 1
Unnecessarily admitting patients with negative initial CT for repeat imaging, which increases costs and healthcare-associated complications without improving outcomes 1, 4
Discontinuing anticoagulation without considering the indication, as the thromboembolic risk may outweigh the small risk of delayed hemorrhage 4, 6, 3
Using PT/INR or aPTT to monitor reversal of factor Xa inhibitors, as these tests are not useful for this purpose 3
Delaying repeat imaging when neurological deterioration occurs in patients with known intracranial hemorrhage 4