What is the management approach for a patient on anticoagulants (blood thinners) and chemotherapy who sustains a head injury?

Management of Head Injury in Patients on Anticoagulants and Chemotherapy

Immediate Imaging is Mandatory

Obtain an immediate non-contrast head CT scan for any patient on anticoagulation who sustains head trauma, regardless of mechanism severity or presence of symptoms. 1, 2

The threshold for CT imaging must be extremely low because:

• Anticoagulated patients have a 3.9% risk of significant intracranial injury versus 1.5% in non-anticoagulated patients 2
• Novel oral anticoagulants (NOACs) carry a 2.6% risk of intracranial hemorrhage, while warfarin carries a 10.2% risk—both substantially higher than patients without anticoagulation 2
• Even ground-level falls warrant immediate imaging in this population 2

Management Algorithm Based on Initial CT Results

If Initial CT Shows Intracranial Hemorrhage

Immediately discontinue anticoagulation and consult neurosurgery. 2

Reversal strategy depends on the specific anticoagulant:

• For warfarin: Administer 4-factor prothrombin complex concentrate (4F-PCC) plus 5mg intravenous vitamin K to achieve INR <1.5 2
• For apixaban or other factor Xa inhibitors: Use andexanet alfa as the specific reversal agent if available; if unavailable, use prothrombin complex concentrate 1, 2
• For dabigatran: Consider idarucizumab if available 2

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). 1, 2

If Initial CT is Negative for Hemorrhage

Do not routinely admit or perform repeat imaging in neurologically stable patients with negative initial CT. 1

This recommendation is based on:

• The American College of Emergency Physicians provides Level B evidence that routine repeat imaging is not indicated in patients at baseline neurologic examination with negative initial CT 1
• Risk of delayed intracranial hemorrhage is low (0.6-6% for warfarin, 0.95% for DOACs) and rarely requires neurosurgical intervention 3, 1, 4
• Most delayed hemorrhages identified on routine repeat imaging do not require intervention 3, 5

However, brief observation (4-6 hours) before discharge should be considered for high-risk features:

• Age >80 years 1, 2
• History of loss of consciousness or amnesia 1, 2
• Glasgow Coma Scale <15 1, 2
• Concomitant use of multiple anticoagulant/antiplatelet agents 2, 4
• Initial INR >3.0 for warfarin patients (14-fold increased risk of delayed hemorrhage) 6

Special Considerations for Chemotherapy Patients

Assess platelet count and coagulation parameters immediately:

• Many chemotherapy regimens cause thrombocytopenia, which compounds bleeding risk 7
• If platelets <50×10^9/L and hemorrhage is present, administer platelet transfusion 7
• Consider the specific chemotherapy agent's effects on hemostasis when planning management 8

Tranexamic Acid Consideration

Administer tranexamic acid (TXA) 1g IV over 10 minutes if intracranial hemorrhage is confirmed, provided treatment can be given within 3 hours of injury. 3

• TXA reduces head injury-related death in mild and moderate traumatic brain injury (risk ratio 0.78,95% CI 0.64-0.95) 3
• Early treatment (within 1 hour) provides greatest benefit 3
• Do not delay TXA administration for viscoelastic assessment results 3

Discharge Instructions for Patients with Negative CT

Provide clear written discharge instructions including:

• Signs of delayed hemorrhage: severe headache, confusion, vomiting, weakness, seizures 1, 2
• Instructions to return immediately or call 911 if symptoms develop 1, 2
• Continue anticoagulation unless specifically instructed otherwise by neurosurgery or the prescribing physician 1

Arrange outpatient follow-up for:

• Fall risk assessment 1, 2
• Reassessment of anticoagulation risk/benefit ratio 1, 2

Critical Pitfalls to Avoid

• Failing to obtain initial CT imaging even with minor mechanisms like ground-level falls 1, 2
• Unnecessarily admitting patients with negative initial CT for routine repeat imaging, which increases costs without improving outcomes 1, 5
• Discontinuing anticoagulation without considering the indication, as thromboembolic risk may outweigh the small risk of delayed hemorrhage 1, 2
• Underestimating hemorrhage progression risk in patients with positive initial CT—these patients require repeat imaging within 24 hours 1, 2
• Ignoring the compounding effect of thrombocytopenia from chemotherapy, which requires separate assessment and management 7