Should I order a CT (computed tomography) scan for a 100-year-old patient who fell and is not on anticoagulation (blood thinner) therapy?

Head CT Recommendation for 100-Year-Old Patient After Fall

Yes, order a head CT scan for this 100-year-old patient who fell, even though they are not on anticoagulation. Age alone (>60-65 years) is a high-risk criterion that warrants head CT imaging in the context of a fall with potential head trauma. 1, 2

Why Age Mandates CT Imaging

• Age >60 years is classified as a high-risk factor across all major clinical decision rules (Canadian CT Head Rule, New Orleans Criteria, and NEXUS Head CT) for clinically important brain injury. 2

• The American College of Emergency Physicians guidelines specifically recommend considering head CT in patients with head trauma if there is age >60 years PLUS one or more additional risk factors (headache, vomiting, drug/alcohol intoxication, short-term memory deficits, physical trauma above clavicle, seizure, GCS <15, focal deficit, or coagulopathy). 1

• For patients ≥65 years without loss of consciousness or amnesia, age alone is a Level B indication to consider head CT, particularly with additional risk factors. 2

• A 100-year-old patient represents extreme age with significantly elevated baseline risk for intracranial injury after falls, even with seemingly minor mechanisms. 3, 1

Critical Information Needed to Refine Decision

You must assess the following to determine urgency and necessity:

• Loss of consciousness or post-traumatic amnesia: If present, this is an absolute indication for immediate CT. 2, 4

• Glasgow Coma Scale score: If GCS <15 at any point, immediate CT is mandatory. 1, 2

• Headache: Any headache after the fall increases risk and supports CT indication. 1, 2

• Vomiting: Two or more episodes significantly increase risk (LR 3.6). 5

• Physical evidence of trauma above the clavicle: Visible scalp injury, hematoma, or facial trauma increases risk. 1, 2

• Mechanism of injury: Dangerous mechanisms (fall from height >1 meter, high-impact fall) warrant imaging. 2, 4

• Focal neurologic deficits: Any weakness, sensory changes, or asymmetric findings mandate immediate CT. 1, 2

Decision Algorithm

If ANY of the following are present → Order CT immediately:

• Loss of consciousness or amnesia 2, 4
• GCS score <15 1, 2
• Vomiting (especially ≥2 episodes) 2, 5
• Headache 1, 2
• Focal neurologic deficit 1, 2
• Signs of skull fracture 2, 5
• Visible trauma above clavicles 1, 2
• Seizure 1, 2

If NONE of the above are present but patient is >65 years old:

• Still strongly consider CT given extreme age (100 years) and fall mechanism, as elderly patients have increased risk even without classic symptoms. 1, 2
• The Canadian CT Head Rule would require CT if age ≥65 years is present with any other criterion. 4, 2

Evidence Supporting Liberal CT Use in Elderly

• Elderly patients (>60 years) with GCS 15 and amnesia had 10% positive CT rate in one large study, with some requiring neurosurgical intervention. 3

• Age >60 years had an odds ratio of 19.2 for intracranial injury in patients with GCS scores 14-15. 3

• Multivariate analysis showed age ≥60 years was significantly correlated with CT abnormality even in mild head injury. 6

Critical Caveats

• Optimal timing: CT performed ≥5 hours post-trauma has better detection rates, but do not delay if high-risk features are present. 2

• Even without anticoagulation, elderly patients have increased bleeding risk due to brain atrophy, fragile vessels, and increased subdural space. 2

• Normal neurologic exam does not exclude intracranial injury: Studies show 14-16% of patients with normal exams and GCS 15 had intracranial injuries. 7, 6

If CT is Not Ordered

This would only be appropriate if ALL of the following are true:

• No loss of consciousness or amnesia
• GCS score of 15 and remains stable
• No headache
• No vomiting
• No visible trauma above clavicles
• No focal neurologic deficits
• No signs of skull fracture
• Patient has reliable caregiver for close observation

Even then, given the patient's extreme age (100 years), the threshold should be very low for obtaining imaging. 1, 2

Provide clear written and verbal discharge instructions about warning signs (worsening headache, vomiting, confusion, altered consciousness) if CT is deferred, though this is not recommended at age 100. 2