What is the recommended initial management and treatment plan for a patient with suspected subarachnoid hemorrhage?

Treatment of Subarachnoid Hemorrhage

Secure the ruptured aneurysm within 24 hours using endovascular coiling as the preferred method for most aneurysms, while simultaneously administering nimodipine 60 mg every 4 hours for 21 days and maintaining systolic blood pressure below 160 mmHg with titratable IV agents until the aneurysm is secured. 1

Immediate Diagnostic Confirmation

• Obtain non-contrast head CT immediately; sensitivity is 98-100% within 12 hours but declines to 93% at 24 hours and 57-85% by day 6. 1, 2
• If CT is negative but clinical suspicion remains high (sudden severe "worst headache of life"), perform lumbar puncture looking for xanthochromia and elevated bilirubin; spectrophotometric analysis >6 hours after onset has 100% sensitivity and 95% specificity. 1, 3
• Once SAH is confirmed, obtain digital subtraction angiography with 3D rotational imaging immediately to identify the aneurysm and plan definitive treatment. 1
• Grade clinical severity using Hunt-Hess or WFNS scales on presentation, as initial grade is the strongest predictor of outcome. 1, 2

Airway and Initial Stabilization

• If intubation is required due to decreased consciousness or inability to protect airway, use rapid-sequence intubation with pre-oxygenation, pharmacologic blunting of sympathetic reflexes, and meticulous avoidance of blood pressure swings. 4, 1
• Place nasogastric or orogastric tube immediately after intubation to reduce aspiration risk. 1
• Maintain adequate oxygenation without hyperventilation; monitor with pulse oximetry and periodic arterial blood gases. 4, 1

Blood Pressure Management (Pre-Aneurysm Securing)

• Target systolic BP <160 mmHg using short-acting titratable IV agents (nicardipine or labetalol) while maintaining mean arterial pressure ≥65 mmHg. 1, 2
• Never permit MAP <65 mmHg, as hypotension worsens cerebral perfusion and outcomes. 1
• Avoid abrupt BP drops; gradual reduction is necessary when severely hypertensive. 1

Nimodipine Therapy (Start Immediately)

• Administer oral nimodipine 60 mg every 4 hours for 21 consecutive days, starting as soon as possible (ideally within 96 hours of SAH onset). 1, 2
• If patient cannot swallow, give via nasogastric tube (80 mg daily) or rectal suppository (325 mg daily). 1
• Nimodipine improves neurological outcomes but does NOT prevent angiographic vasospasm. 1, 2

Aneurysm Securing (Within 24 Hours)

Timing

• Secure the aneurysm as early as feasible, ideally within 24 hours, because rebleeding carries 70-80% mortality and risk is highest in the first 2-12 hours (4-13.6% rebleed within 24 hours). 1, 2

Treatment Selection Algorithm

For anterior circulation aneurysms amenable to both techniques:

• Endovascular coiling is preferred over surgical clipping to achieve superior 1-year functional outcomes. 1, 2
• Exception: Consider clipping in patients <40 years old for enhanced long-term durability. 1

For posterior circulation aneurysms:

• Endovascular coiling is strongly favored (relative risk 0.41 for death or dependency vs clipping). 1, 2

For large intraparenchymal hematoma (>50 cm³) with depressed consciousness but retained spontaneous respiration and pain response:

• Emergency surgical clot evacuation combined with aneurysm clipping reduces mortality from ~80% to ~27%. 1

For wide-neck aneurysms not amenable to primary coiling or clipping:

• Stent-assisted coiling or flow-diverter devices are reasonable options. 1

For ruptured saccular aneurysms suitable for primary coiling or clipping:

• AVOID stents or flow-diverters because they require dual antiplatelet therapy and increase hemorrhagic complications (including ventriculostomy-related bleeding). 1

For fusiform or blister aneurysms:

• Flow-diverter devices are reasonable to reduce mortality. 1

Treatment Goals

• Aim for complete aneurysm obliteration whenever technically possible; incomplete obliteration significantly raises rebleeding risk and need for retreatment. 1, 2
• If complete obliteration cannot be achieved, partial treatment securing the rupture site is acceptable with planned retreatment within 1-3 months. 1

Management of Acute Hydrocephalus

• If acute symptomatic hydrocephalus develops, perform urgent CSF diversion via external ventricular drain or lumbar drain depending on clinical scenario. 1, 2
• Use standardized EVD bundle protocols to minimize complications. 1

Fluid and Hemodynamic Management

• Maintain euvolemia and normal circulating blood volume; prophylactic hypervolemia ("triple-H" therapy) does NOT improve outcomes and may cause harm. 1, 2

Management of Delayed Cerebral Ischemia (If It Develops)

• Induce hypertension while maintaining euvolemia for symptomatic DCI, unless baseline BP is already elevated or cardiac status precludes it. 1, 2
• Consider cerebral angioplasty and/or selective intra-arterial vasodilator therapy as adjuncts or alternatives if hypertensive therapy fails. 1

Antiplatelet and Anticoagulation Management

• Withhold aspirin and other antiplatelet agents until after aneurysm is secured. 1
• If patient is anticoagulated, perform emergent reversal based on clinical judgment. 1

Antifibrinolytic Therapy (Very Limited Role)

• Short-course antifibrinolytics (<72 hours) such as tranexamic acid may be considered ONLY when aneurysm securing is unavoidably delayed, the patient has high rebleeding risk, and no contraindications exist. 1
• The 2023 ULTRA trial showed tranexamic acid does NOT significantly reduce rebleeding or improve outcomes when aneurysms are secured early. 1
• Antifibrinolytics increase deep-vein thrombosis risk (no increase in pulmonary embolism). 1
• Neither tranexamic acid nor aminocaproic acid is FDA-approved for SAH. 1

Transfer to Specialized Centers

• Immediately transfer patients to high-volume centers (>35 SAH cases/year) with dedicated cerebrovascular neurosurgeons, endovascular specialists, and neurocritical care teams. 1, 2
• Treatment decisions should involve multidisciplinary team comprising both endovascular and microsurgical specialists. 1, 2

Venous Thromboembolism Prophylaxis

• Initiate pharmacologic VTE prophylaxis once the aneurysm has been secured. 1, 2

Post-Treatment Imaging Follow-Up

• Obtain immediate post-treatment vascular imaging to detect residual aneurysm or recurrence. 1, 2
• Schedule follow-up vascular imaging at 6 months and 18 months; retreatment should be strongly considered for clinically significant growing remnants. 1, 2

Critical Pitfalls to Avoid

• Do NOT delay aneurysm treatment beyond 24 hours when feasible; early rebleeding risk increases progressively with time (70-80% mortality). 1, 2
• Do NOT employ prophylactic hypervolemia ("triple-H" therapy); it lacks supporting evidence and may be harmful. 1, 2
• Do NOT use stents or flow-diverters for ruptured saccular aneurysms amenable to primary coiling or clipping due to higher complication rates. 1
• Do NOT allow hypotension (MAP <65 mmHg) during blood pressure management. 1
• Do NOT miss the diagnosis; SAH is misdiagnosed in up to 12% of cases, so maintain high suspicion for sudden severe headache. 1, 2