Hunt & Hess scale
Clinical grade of aneurysmal subarachnoid haemorrhage
Sources last checked: 2026-10-13
Hunt & Hess scale
Clinical grade of aneurysmal subarachnoid haemorrhage
Terms such as 'drowsy' and 'stupor' are not operationalised, so inter-rater agreement is modest; the GCS-based WFNS grade is more reproducible. Grade 0 and Ia (Hunt & Kosnik 1974) are not included.
Interpretation
| Grade I | Good clinical grade. |
|---|---|
| Grade II | Good clinical grade. |
| Grade III | Intermediate grade. |
| Grade IV | Poor grade (IV–V). |
| Grade V | Poor grade (IV–V). |
What is the Hunt & Hess scale?
The Hunt & Hess scale grades the clinical severity of aneurysmal subarachnoid haemorrhage from I (minimal headache) to V (deep coma). Hunt and Hess described it in 1968 to relate surgical risk to the patient's condition at the time of aneurysm repair. It remains widely quoted in neurosurgery, although its descriptive terms are less reproducible than the GCS-based WFNS grade.
When to use it
- Initial clinical grading of confirmed aneurysmal subarachnoid haemorrhage.
- Communication with neurosurgery and neurointervention teams.
- Prognostic stratification together with WFNS and imaging grades.
When not to use it
- Before SAH is confirmed; it is a grading tool, not a diagnostic one.
- As the only grading scale when reproducibility matters (trials, registries) — pair it with WFNS.
How it is calculated
| Criterion | Points |
|---|---|
| Clinical picture | |
| I — Asymptomatic or minimal headache, slight nuchal rigidity | 1 |
| II — Moderate–severe headache, nuchal rigidity, no deficit except cranial nerve palsy | 2 |
| III — Drowsiness, confusion or mild focal deficit | 3 |
| IV — Stupor, moderate–severe hemiparesis, possibly early decerebrate rigidity | 4 |
| V — Deep coma, decerebrate rigidity, moribund | 5 |
| Serious systemic disease or severe vasospasm on angiography (+1 grade) | +1 |
Clinical pearls and limitations
- Terms such as 'drowsy' and 'stupor' are not operationalised, so inter-rater agreement is modest; the GCS-based WFNS grade is more reproducible. Grade 0 and Ia (Hunt & Kosnik 1974) are not included.
- The original scale moves a patient one grade worse for serious systemic disease (e.g. hypertension, diabetes, severe atherosclerosis, chronic lung disease) or severe angiographic vasospasm; many centres omit this.
- Grades IV–V are usually called poor grade.
- Re-grade after treating acute hydrocephalus or seizures; the initial grade may overstate severity.
Frequently asked questions
What is the difference between Hunt & Hess and WFNS?
Hunt & Hess uses descriptive terms (drowsy, stupor); WFNS uses GCS plus focal motor deficit, which makes it more reproducible between raters.
What is poor-grade SAH?
Usually Hunt & Hess or WFNS grade IV–V.
Does the systemic disease upgrade still apply?
It is part of the 1968 scale, but practice varies. State whether you applied it when you report the grade.
Evidence and guidelines
- Primary source: Hunt WE, Hess RM. Surgical risk as related to time of intervention in the repair of intracranial aneurysms. J Neurosurg 1968;28(1):14-20.
- Rosen DS, Macdonald RL. Subarachnoid hemorrhage grading scales: a systematic review. Neurocrit Care 2005;2(2):110-118.
- Steiner T et al. European Stroke Organization guidelines for the management of intracranial aneurysms and subarachnoid haemorrhage. Cerebrovasc Dis 2013;35(2):93-112.
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