When to Send Someone to the ER After Hitting Their Head
Any patient with head trauma should be taken to the emergency department if they have loss of consciousness, amnesia, confusion, persistent headache, vomiting, neurological deficits, visible skull fracture, or a Glasgow Coma Scale (GCS) score less than 15 1.
Immediate ER Indications
Send the patient to the ER immediately if ANY of the following are present:
- Altered mental status (GCS <15 or confusion)
- Loss of consciousness at any point after injury
- Amnesia (inability to remember events before or after the injury)
- Persistent or worsening headache
- Vomiting (especially if repeated)
- Neurological deficits (weakness, numbness, vision changes, speech problems, seizures)
- Signs of skull fracture (visible deformity, clear fluid from nose/ears, Battle's sign, raccoon eyes)
- Mechanism of high-risk injury (fall from height, high-speed collision, assault)
High-Risk Populations Requiring Lower Threshold for ER Evaluation
Patients on Anticoagulants or Antiplatelet Agents
The threshold for ER evaluation and imaging is extremely low for patients taking blood thinners 1. These patients have significantly higher risk of intracranial hemorrhage:
- Warfarin users: 3.9% intracranial injury rate vs 1.5% in non-anticoagulated patients
- NOACs (apixaban, rivaroxaban, dabigatran): 2.6% ICH rate (lower than warfarin but still elevated)
- Antiplatelet agents (clopidogrel, ticagrelor): Similar elevated risk
- Aspirin in elderly patients (≥65 years): Up to 4% delayed ICH rate, with concerning outcomes 1
Send these patients to the ER even with seemingly minor head trauma, particularly if they are elderly or have any of the symptoms listed above.
Elderly Patients (≥65 years)
Older adults are at substantially higher risk due to:
- Brain atrophy creating more space for bleeding
- Higher fall risk
- Frequent anticoagulant/antiplatelet use
- Baseline cognitive issues that may mask symptoms 2
Elderly patients on aspirin with loss of consciousness, amnesia, or GCS <15 may require observation even with normal initial imaging 1.
Other High-Risk Groups Requiring ER Evaluation
- Coagulopathies (hemophilia, liver disease)
- Alcohol intoxication (masks symptoms and increases bleeding risk)
- Drug abuse
- History of epilepsy
- Previous neurosurgical procedures
- Frail or cognitively impaired patients without adequate home supervision 3
Patients Who May NOT Need Immediate ER Visit
A patient with GCS 15, no loss of consciousness, no amnesia, no persistent headache, no vomiting, and no risk factors can potentially be observed at home with strict return precautions 3, 4.
Critical Home Observation Requirements:
- Responsible adult must be present to monitor the patient
- Wake patient every 2-3 hours during first 24 hours
- Clear written instructions on warning signs
- Ability to return immediately if symptoms develop
Return to ER Immediately If:
- Worsening headache
- Repeated vomiting
- Confusion or difficulty waking
- Weakness or numbness
- Vision changes
- Slurred speech
- Seizures
- Clear fluid from nose or ears
- Unequal pupils
Important Caveats
Delayed presentation (>24 hours after injury) does not eliminate risk. While some research suggests lower rates of intracranial injury in delayed presenters (2.2-6.3%), clinical decision rules like NICE guidelines are less sensitive (83% vs 93%) in this population and may miss injuries 5, 6. When in doubt after delayed presentation with new symptoms, send to ER.
The absence of skull fracture on examination does not rule out intracranial injury, though its presence significantly increases risk and mandates CT imaging 3, 4.
Patients with isolated scalp lacerations but otherwise normal examination and no risk factors may be managed with wound care alone, but maintain low threshold for ER referral if any concerning features develop.