neurologystaging system

Hunt & Hess Grade (SAH)

The Hunt & Hess grading system classifies the clinical severity of aneurysmal subarachnoid haemorrhage from Grade I (asymptomatic/mild headache) to Grade V (deep coma). It is the most widely used clinical SAH grading system and correlates with surgical risk and overall prognosis.

inputs

✓ when to use

Use in patients with confirmed or suspected aneurysmal SAH to grade clinical severity, guide management intensity, and communicate prognosis. Grade at the time of initial assessment and reassess after resuscitation/stabilisation. Good-grade (I–II) patients generally undergo early aneurysm intervention.

✗ when not to use

Hunt & Hess is a clinical grading system, not a diagnostic tool. It does not account for aneurysm size, location, or radiographic SAH severity (Fisher/modified Fisher grade provides this). Inter-rater reliability is moderate — the WFNS scale (based on GCS + focal deficit) provides a more standardised alternative. Not applicable for non-aneurysmal SAH (perimesencephalic, traumatic).

clinical pearls

  • Hunt & Hess Grade I–III ('good grade') patients generally undergo early aneurysm intervention (within 24–72 hours) — either endovascular coiling or surgical clipping depending on aneurysm characteristics and centre expertise.
  • Grade IV–V ('poor grade') management is more controversial. Some centres offer intervention if clinical trajectory improves after initial resuscitation. Others adopt a more conservative approach. Goals-of-care discussions are essential.
  • The WFNS scale is the main alternative — it uses GCS (objective) + presence of focal deficit (binary), making it more standardised and reproducible. Many centres report both Hunt & Hess and WFNS.
  • Clinical grade can fluctuate, especially after interventions (CSF drainage, BP management). Reassess after stabilisation for a more representative grade.
  • SAH severity is assessed by both clinical grade (Hunt & Hess or WFNS) and radiographic grade (Fisher/modified Fisher). Both independently predict outcome and vasospasm risk.

related tools

wfns-sahMore standardised GCS-based SAH gradinggcsConsciousness assessment underlying WFNSnihssIf stroke vs SAH being evaluated