Hunt and Hess Scale Calculator (Subarachnoid Hemorrhage Grade)
Grade aneurysmal subarachnoid hemorrhage with the Hunt and Hess scale (I–V) from the clinical picture, including the one-grade upgrade for serious systemic disease or severe vasospasm.
How it works
Grade I: asymptomatic or minimal headache and slight neck stiffness · Grade II: moderate to severe headache, neck stiffness, no deficit other than cranial nerve palsy · Grade III: drowsiness, confusion or mild focal deficit · Grade IV: stupor, moderate to severe hemiparesis, possible early decerebrate rigidity · Grade V: deep coma, decerebrate rigidity, moribund. Serious systemic disease or severe angiographic vasospasm → add one grade (maximum V).
The Hunt and Hess scale (Hunt and Hess, Journal of Neurosurgery 1968) was introduced to estimate surgical risk after a ruptured intracranial aneurysm and is still one of the two most used clinical grading systems for subarachnoid hemorrhage (SAH), alongside the WFNS scale. A higher grade means worse level of consciousness and neurological state and a worse outcome. Grades I–III are usually called good-grade SAH and grades IV–V poor-grade SAH. The scale is subjective — terms such as drowsy and stupor vary between observers — so many centers record the WFNS grade, which is anchored to the Glasgow Coma Scale, as well.
Worked example
A patient with a ruptured aneurysm has a severe headache and neck stiffness with no focal deficit (Grade II picture) and no serious systemic disease: Hunt and Hess Grade II — a good-grade SAH. If the same patient had severe vasospasm on angiography, the grade would move to Grade III.
Sources: Hunt WE, Hess RM. Surgical risk as related to time of intervention in the repair of intracranial aneurysms. J Neurosurg 1968;28:14–20 · Hoh BL et al. 2023 AHA/ASA Guideline for the Management of Aneurysmal Subarachnoid Hemorrhage. Stroke 2023
Frequently asked questions
What do the Hunt and Hess grades mean?
Grade I is the mildest (little or no headache), grade II a severe headache and neck stiffness without deficits, grade III drowsiness or a mild focal deficit, grade IV stupor or marked hemiparesis, and grade V deep coma. Outcome worsens with each grade.
Why add a grade for systemic disease?
Hunt and Hess placed patients with serious systemic disease (such as hypertension, diabetes, severe atherosclerosis or chronic lung disease) or severe vasospasm on angiography in the next less favorable grade, because these conditions raised surgical risk.
What is the difference between Hunt and Hess and WFNS?
Hunt and Hess uses descriptive clinical terms, while the WFNS scale uses the Glasgow Coma Scale and the presence of a motor deficit, which makes it more reproducible. Both run from I to V.
What is poor-grade subarachnoid hemorrhage?
Hunt and Hess grade IV–V (or WFNS IV–V). These patients have a much higher risk of death and disability, although some still recover well with aggressive neurocritical care.
Related calculators
Clinical decision tool for education and for use by trained clinicians alongside clinical judgement — not a diagnosis and not a substitute for medical assessment. Scores and cut-offs come from the cited validation studies and may not apply to every patient; follow local protocols.