Subarachnoid Hemorrhage Medical Slides

Present the sensitivity timeline: non-contrast CT is 98% sensitive within 6 hours but drops to 93% at 12 hours and <50% after 5 days. If CT is negative and clinical suspicion remains, lumbar puncture for xanthochromia (spectrophotometry, positive after 12 hours of onset) is required. CTA has replaced conventional angiography as the first-line vascular imaging modality, with >98% sensitivity for aneurysms >3 mm.

Present the timeline: vasospasm peaks at days 7-10 post-bleed. Nimodipine 60 mg q4h for 21 days is the only proven neuroprotective agent (reduces poor outcome by 40% though does not prevent angiographic vasospasm). Monitor with daily transcranial Doppler (MCA velocity >120 cm/s concerning, >200 cm/s severe). Rescue options for symptomatic vasospasm: induced hypertension, intra-arterial verapamil/nicardipine, and balloon angioplasty.

Reference the ISAT trial (2002) showing endovascular coiling reduced poor outcomes by 23% compared to surgical clipping at 1 year for anterior circulation aneurysms amenable to both. Present selection factors: coiling preferred for posterior circulation, elderly patients, and poor clinical grade; clipping preferred for MCA aneurysms with wide necks, associated hematomas requiring evacuation, and giant/fusiform aneurysms. Emphasize the BRAT trial long-term data showing convergence of outcomes at 10 years.