In an elderly patient on warfarin who sustains a ground‑level fall without obvious head injury, should an emergent non‑contrast head CT be obtained?

Head CT Guidelines for Elderly Patients on Warfarin After Ground-Level Fall Without Obvious Head Injury

An emergent non-contrast head CT should be obtained in all elderly patients on warfarin who sustain a ground-level fall, regardless of the absence of obvious head injury or symptoms. 1, 2

Rationale for Mandatory Imaging

The threshold for imaging anticoagulated patients after any head trauma is extremely low because of the dramatically increased risk of intracranial hemorrhage and associated mortality:

• Warfarin increases the risk of significant intracranial injury to 3.9% compared to 1.5% in non-anticoagulated patients – more than double the baseline risk. 1
• Among anticoagulated patients with minor head injuries and a Glasgow Coma Scale of 15 (neurologically intact), 29% had intracranial hemorrhage despite appearing well. 2
• Warfarin carries the highest hemorrhage risk at 10.2% compared to 2.6% for direct oral anticoagulants. 1
• The mortality rate in anticoagulated elderly patients with head injury reaches 50% when intracranial hemorrhage occurs, far exceeding rates in non-anticoagulated patients with similar injuries. 3

Why "No Obvious Head Injury" Does Not Exclude Imaging

The American College of Emergency Physicians explicitly recommends imaging for all patients on anticoagulants after head trauma regardless of clinical presentation or mechanism severity. 1, 4 This is because:

• Loss of consciousness is strongly associated with mortality but its absence does not reliably exclude intracranial injury or risk of death in warfarin patients. 5
• Ground-level falls account for 34.6% of all trauma deaths in patients ≥65 years, with significantly higher rates of intracranial injury than younger patients. 2
• The consequences of missing an early hemorrhage are catastrophic given the high mortality rate. 1

Management Algorithm After CT Results

If CT Shows Intracranial Hemorrhage:

1. Immediately discontinue warfarin 2, 4
2. Reverse anticoagulation urgently:
   • Administer 4-factor prothrombin complex concentrate (4F-PCC) to achieve INR <1.5 2, 4
   • Give 5 mg intravenous vitamin K simultaneously 2, 4
   • Recheck INR after reversal to confirm adequacy 2
3. Obtain urgent neurosurgical consultation 2, 4
4. Obtain repeat head CT within 24 hours because anticoagulated patients have a 3-fold increased risk of hemorrhage expansion (26% vs 9%). 2, 4

If Initial CT is Negative:

Neurologically intact patients with negative initial CT can be safely discharged without repeat imaging or prolonged observation. 1 The evidence supporting this includes:

• The risk of delayed intracranial hemorrhage requiring intervention after negative initial CT is extremely low (<1%) in neurologically intact patients. 1, 4
• In one study of 178 patients on warfarin or NOACs with negative initial CT, only 3 (1.7%) developed delayed ICH over 30 days, with only one death and none requiring neurosurgery. 1
• Do not routinely discontinue warfarin after negative initial CT in neurologically intact patients, as thromboembolic risk may outweigh the small risk of delayed hemorrhage. 2, 4

High-Risk Features Requiring Brief Observation

Consider 4-6 hours of observation before discharge if the patient has: 2, 4

• Age >80 years
• History of loss of consciousness or post-traumatic amnesia
• Glasgow Coma Scale <15
• Multiple anticoagulant/antiplatelet agents

Mandatory Discharge Instructions

Provide clear written instructions including: 1, 2

• Warning signs of delayed hemorrhage (severe headache, vomiting, confusion, weakness, seizure)
• Instructions to return immediately or call 911 if symptoms develop
• Outpatient referral for fall risk assessment
• Reassessment of anticoagulation risk/benefit ratio

Common Pitfalls to Avoid

• Failing to obtain CT based on "minor mechanism" – the mechanism severity does not predict injury in anticoagulated elderly patients. 1, 2
• Assuming absence of loss of consciousness excludes significant injury – 27% of warfarin patients with intracranial injury had no documented LOC. 5
• Unnecessarily discontinuing warfarin after negative CT – this increases thromboembolic risk without clear benefit. 2, 4
• Ordering routine repeat imaging in stable patients with negative initial CT – this increases costs and radiation exposure without changing outcomes. 1