378 Ch 377. Intracerebral Hemorrhage (ICH) and Subarachnoid Hemorrhage (SAH)

ICH (10% of strokes) = bleeding into brain parenchyma；etiology: hypertensive (most common — deep locations: basal ganglia/putamen, thalamus, pons, cerebellum) + cerebral amyloid angiopathy (CAA — lobar in elderly) + AVM/cavernoma + tumor + anticoagulation + drug-induced (cocaine, amphetamine) + venous infarct + hemorrhagic transformation；clinical: rapid onset deficit + headache + LOC + vomiting + ↑ ICP；diagnosis: CT head non-contrast — hyperdense (acute); management: BP control (INTERACT-3 2023, target SBP 140 mmHg) + reverse anticoagulation + neurosurgery (cerebellar > 3 cm, IVH with hydrocephalus, deteriorating); STICH-I + STICH-II clot evacuation no benefit for supratentorial except select; minimally invasive evacuation (ENRICH 2024) showing promise；SAH (5% of strokes) = bleeding into subarachnoid space；etiology: ruptured saccular aneurysm (~ 80%) + traumatic + AVM + perimesencephalic (non-aneurysmal) + RCVS；presentation: “worst headache of life” thunderclap + meningismus + photophobia + LOC + focal deficits + seizures；Hunt-Hess + WFNS + Fisher grading；workup: CT (highly sensitive in first 6 hr) + LP if CT negative (xanthochromia)；aneurysm management: coiling > clipping for most (ISAT trial) + endovascular preferred；complications: rebleeding + vasospasm (peaks day 4-14) + hydrocephalus + hyponatremia + cardiac (Takotsubo, neurogenic pulmonary edema)；nimodipine 60 mg q4h × 21 days reduces poor outcomes from vasospasm。