Emergency Department Evaluation of Headache

Initial Assessment

The American Heart Association suggests evaluating for "red flags" that suggest a secondary headache disorder requiring urgent attention, including sudden onset/thunderclap headache, which may indicate subarachnoid hemorrhage 1
The American Academy of Neurology recommends assessing for headache that worsens when lying down or bending over, which may suggest increased intracranial pressure 2
The British Medical Journal suggests evaluating for new unexplained bruising or bleeding, which may indicate coagulopathy or vaccine-induced immune thrombocytopenia and thrombosis (VITT) 3
The American College of Emergency Physicians recommends assessing for shortness of breath, leg swelling, or persistent abdominal pain, which may suggest thrombosis 3
The Neurocritical Care Society suggests evaluating for neurological deficits, which may indicate stroke, hemorrhage, or mass lesion 1

The American Heart Association recommends non-contrast head CT as the first-line imaging study for evaluating headache 1
The World Federation of Neurosurgical Societies suggests considering CT venography or MR venography if there is concern for cerebral venous thrombosis 4
The American College of Radiology recommends brain MRI with and without contrast if available, particularly for persistent headache 5

The British Medical Journal suggests complete blood count (CBC) to evaluate for thrombocytopenia, which may indicate VITT if platelet count <150×10^9/L 3
The American Society of Hematology recommends coagulation studies, including D-dimer, PT/INR, and PTT, to assess for coagulopathy 3
The National Kidney Foundation suggests basic metabolic panel to evaluate for electrolyte abnormalities and renal function assessment 5

The British Medical Journal recommends considering VITT if patient received COVID-19 vaccination 5-30 days prior to symptom onset, with diagnostic criteria including thrombocytopenia, D-dimer >4000 μg/mL, presence of thrombosis, and positive anti-PF4 antibodies 3
The World Federation of Neurosurgical Societies suggests considering cerebral venous thrombosis if patient presents with persistent headache, with MRI findings including signal loss of affected cortical vein in T2-susceptibility-weighted gradient echo sequences 4
The American Academy of Neurology recommends considering migraine if patient has history of similar headaches, with diagnostic criteria including headache lasting 4-72 hours, unilateral location, pulsating quality, moderate/severe intensity, and associated nausea/vomiting, photophobia, phonophobia 2

The American College of Emergency Physicians recommends treatment directed at the underlying cause of headache 6
The American Academy of Neurology suggests NSAIDs, triptans, or combination analgesics for acute treatment of primary headache disorders, and avoiding opioids for headache management 7
The British Medical Journal recommends non-heparin based anticoagulants and intravenous immunoglobulin for treatment of VITT 3
The World Federation of Neurosurgical Societies suggests anticoagulation and consideration of neurosurgical consultation if intracranial hemorrhage is present for treatment of cerebral venous thrombosis 4