Hunt-Hess Scale (SAH)
Assign the standard five-grade Hunt–Hess clinical category for aneurysmal subarachnoid hemorrhage from the documented presentation, with exact criteria and neutral limitations.
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About
Formula
Interpretation
Exact five-grade criteria
- I: Asymptomatic, mild headache, slight nuchal rigidity
- II: Moderate to severe headache, nuchal rigidity, no neurologic deficit other than cranial nerve palsy
- III: Drowsiness, confusion, or mild focal neurologic deficit
- IV: Stupor, moderate to severe hemiparesis
- V: Coma with decerebrate posturing
When to record the grade
Record the first, admission, or another explicitly stated assessment time. Serial grades can change; do not present a later grade as the admission grade, and record both time and examination state.
Confounders and reversible deterioration
Sedation, intubation, paralytic medication, postictal state, hydrocephalus, rebleeding and metabolic abnormalities can affect assessment. Record and interpret these clinically; this page does not automatically correct the grade.
Prognostic limitations
Higher grades have historically been associated with worse average outcomes across cohorts. This page does not convert a grade into an individual mortality probability because outcomes vary with patient factors, treatment era, aneurysm and hemorrhage features, complications and care setting. Age, comorbidity, hemorrhage burden, intraventricular or intracerebral hemorrhage, rebleeding, hydrocephalus, delayed cerebral ischemia and treatment matter; the grade cannot justify limiting treatment or declaring care futile.
Related clinical and imaging scales
WFNS primarily uses GCS and focal deficit; GCS records consciousness; Fisher and modified Fisher describe CT blood burden. These answer different questions and are not interchangeable. mRS is an outcome/disability scale, not an admission SAH clinical grade.
Current guideline context
The 2023 AHA/ASA aneurysmal SAH guideline replaces the 2012 guideline. Current management relies on multidisciplinary neurovascular assessment; this page does not perform transport, aneurysm treatment, blood-pressure, delayed cerebral ischemia or other treatment algorithms.
References
- 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. PMID 5635959. DOI 10.3171/jns.1968.28.1.0014.
- NINDS Common Data Elements. Hunt and Hess scale — Qualified.
- Hoh BL, et al. 2023 Guideline for the Management of Patients With Aneurysmal Subarachnoid Hemorrhage. Stroke. 2023;54(7):e314–e370. PMID 37212182. DOI 10.1161/STR.0000000000000436.
- Rosen DS, Macdonald RL. Subarachnoid hemorrhage grading scales: a systematic review. Neurocrit Care. 2005;2(2):110–118. PMID 16159052. DOI 10.1385/NCC:2:2:110.
- Degen LAR, et al. Interobserver variability of grading scales for aneurysmal subarachnoid hemorrhage. Stroke. 2011;42(6):1546–1549. PMID 21527761. DOI 10.1161/STROKEAHA.110.601211.
- Lindsay KW, Teasdale GM, Knill-Jones RP. Observer variability in assessing the clinical features of subarachnoid hemorrhage. J Neurosurg. 1983;58(1):57–62. PMID 6847910. DOI 10.3171/jns.1983.58.1.0057.
- Report of World Federation of Neurological Surgeons Committee on a Universal Subarachnoid Hemorrhage Grading Scale. J Neurosurg. 1988;68(6):985–986. PMID 3131498. DOI 10.3171/jns.1988.68.6.0985.
- Oshiro EM, et al. A new subarachnoid hemorrhage grading system based on the Glasgow Coma Scale: a comparison with the Hunt and Hess and World Federation of Neurological Surgeons Scales in a clinical series. Neurosurgery. 1997;41(1):140–147. PMID 9218306. DOI 10.1097/00006123-199707000-00029.
FAQ
It classifies current clinical presentation in aneurysmal subarachnoid hemorrhage using five ordinal grades, I–V. It is not a diagnosis test or arithmetic score.
Grade I: Asymptomatic, mild headache, slight nuchal rigidity. Grade II: Moderate to severe headache, nuchal rigidity, no neurologic deficit other than cranial nerve palsy. Grade III: Drowsiness, confusion, or mild focal neurologic deficit. Grade IV: Stupor, moderate to severe hemiparesis. Grade V: Coma with decerebrate posturing.
No. It describes presentation after clinical assessment; CT, CTA, DSA and other appropriate evaluation establish diagnosis.
Record a stated assessment time, commonly first or admission assessment, with the actual examination state. Do not present a later grade as the admission grade.
Yes. Clinical status can change with rebleeding, hydrocephalus, delayed cerebral ischemia or treatment; record timing and comparability factors with serial grades.
Sedation, intubation, paralytic medication and postictal state can confound examination and must be documented alongside other reversible factors; this page does not correct a grade automatically.
No. Higher grades have historically been associated with worse cohort outcomes, but this page does not provide a fixed individual mortality percentage because patient, aneurysm, hemorrhage, complication, treatment-era and care-setting factors vary.
No. It cannot independently decide clipping, coiling or treatment timing. Decisions require imaging, aneurysm features, timing, confounders and neurovascular-team assessment.
Hunt–Hess is a clinical-presentation classification; WFNS primarily uses GCS and focal deficit. They answer related but different questions and are not interchangeable.
Fisher and modified Fisher describe CT blood burden, while Hunt–Hess describes clinical presentation. Neither replaces the other.
The scale has subjective elements and observer variability, particularly when examination findings are affected by confounders. Standardized documentation improves communication.
It is primarily used in aneurysmal SAH. Other causes require interpretation under the applicable clinical protocol rather than automatic use of this scale.
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Disclaimer
Educational and informational reference only. Not intended to replace professional medical advice, diagnosis, treatment, or independent verification.