Fisher Grade

Grades subarachnoid hemorrhage on CT to predict risk of vasospasm

Indication

id: fisher; label: CT Findings; type: options; options: label: Grade 0 — No SAH or IVH; value: 0; label: Grade 1 — Thin SAH, no IVH; value: 1; label: Grade 2 — Thin SAH with IVH; value: 2; label: Grade 3 — Thick SAH, no IVH; value: 3; label: Grade 4 — Thick SAH with IVH; value: 4

function(score) { if (score === 0) return { risk: 'Grade 0', tier: 'No SAH', action: 'No blood seen. If clinical suspicion high, consider LP. Vasospasm risk: 0%.', color: 'green' }; if (score === 1) return { risk: 'Grade 1', tier: 'Low Vasospasm Risk', action: 'Thin SAH without IVH. Vasospasm risk ~24%. Start nimodipine 60mg q4h. Neurosurgery consult.', color: 'yellow' }; if (score === 2) return { risk: 'Grade 2', tier: 'Moderate Vasospasm Risk', action: 'Thin SAH with IVH. Vasospasm risk ~33%. Nimodipine. Ventriculostomy if needed. ICU admission.', color: 'yellow' }; if (score === 3) return { risk: 'Grade 3', tier: 'High Vasospasm Risk', action: 'Thick SAH without IVH. Vasospasm risk ~33%. Nimodipine. Urgent angiography. ICU admission.', color: 'red' }; return { risk: 'Grade 4', tier: 'Highest Vasospasm Risk', action: 'Thick SAH with IVH. Vasospasm risk ~40%. ICU admission. Nimodipine. EVD placement. Urgent angiography and intervention.', color: 'red' }; }

Vasospasm typically occurs days 3-14 after SAH, peaking days 7-10
Nimodipine 60mg PO q4h for 21 days — only proven medication to reduce poor outcomes from vasospasm
IVH (intraventricular hemorrhage) is an independent risk factor for vasospasm and poor outcome