What is the management of subarachnoid hemorrhage?

Management of Subarachnoid Hemorrhage

Immediate Diagnosis and Initial Stabilization

Obtain a noncontrast head CT immediately for any patient with acute severe headache; if negative and clinical suspicion remains high, proceed directly to lumbar puncture looking for xanthochromia and elevated bilirubin. 1

• CT sensitivity is time-critical: 98-100% within 12 hours, declining to 93% at 24 hours and 57-85% by day 6 1, 2
• Misdiagnosis occurs in up to 12% of cases, making high clinical suspicion essential 1, 3
• Spectrophotometric analysis of cerebrospinal fluid performed >6 hours after onset has 100% sensitivity and 95.2% specificity 2
• After SAH confirmation, perform digital subtraction angiography with 3-dimensional rotational angiography to identify the aneurysm and plan treatment 4, 2

Rapidly assess clinical severity using Hunt and Hess or World Federation of Neurological Surgeons scales, as initial grade is the strongest predictor of outcome. 4, 1, 3

Blood Pressure Management Before Aneurysm Securement

Control blood pressure with short-acting titratable intravenous agents (nicardipine or labetalol), targeting systolic BP <160 mmHg while maintaining mean arterial pressure ≥65 mmHg. 1, 2, 3

• Balance rebleeding risk against cerebral perfusion; avoid both severe hypertension and hypotension 4, 2
• Gradual BP reduction is necessary when severely hypertensive (systolic >180-200 mmHg) 2
• Critical pitfall: Never allow hypotension (MAP <65 mmHg), as this compromises cerebral perfusion and worsens outcomes 2

Aneurysm Securement: Timing and Modality

Secure the ruptured aneurysm as early as feasible, ideally within 24 hours, as this is the only proven method to reduce catastrophic rebleeding (mortality 70-80%). 1, 2, 3

• Rebleeding risk is highest in the first 24 hours, with 15% "ultraearly rebleeding" and 70% occurring within 2 hours 1, 2
• Critical pitfall: Do not delay aneurysm treatment beyond 24 hours when feasible 2

Treatment Modality Selection

For anterior circulation aneurysms amenable to both techniques, endovascular coiling is preferred over surgical clipping to achieve better 1-year functional outcomes. 4, 1, 2, 3

For posterior circulation aneurysms, endovascular coiling is strongly favored, with a relative risk of 0.41 for death or dependency compared to clipping. 4, 2

For patients with large intraparenchymal hematoma (>50 cm³) and depressed consciousness but spontaneous respiration and pain response, perform emergency surgical clot evacuation combined with aneurysm clipping, which reduces mortality from 80% to 27%. 4, 2

• The desire for rapid clot evacuation generally favors surgery without delay and concomitant aneurysm clipping 4
• Complete aneurysm obliteration should be achieved whenever technically possible 4, 1, 3

Critical pitfall: For ruptured saccular aneurysms amenable to primary coiling or clipping, avoid stent-assisted coiling or flow diverters in the acute phase, as they require dual antiplatelet therapy and increase hemorrhagic complications, particularly ventriculostomy-related hemorrhage. 4, 2

• Stents or flow diverters are reasonable only for wide-neck aneurysms not amenable to primary coiling or clipping 2

Multidisciplinary Evaluation

Treatment decisions must involve specialists with expertise in both endovascular and surgical techniques, individually or as a team 4, 2

Nimodipine Administration

Administer oral nimodipine 60 mg every 4 hours for 21 consecutive days, starting as soon as possible within 96 hours of hemorrhage onset. 4, 1, 3, 5

• This is a Class I, Level of Evidence A recommendation that reduces cerebral infarction by 34% and poor outcomes by 40% 1
• Nimodipine improves neurological outcomes but does not prevent angiographic vasospasm 4
• If the patient cannot swallow: Make a hole in both ends of the capsule with an 18-gauge needle, extract contents into a syringe labeled "Not for IV Use," and administer via nasogastric tube followed by 30 mL normal saline flush 5
• Alternative routes include enteral tube (≈80 mg daily) or rectal suppository (≈325 mg daily) 2
• Critical pitfall: Never administer nimodipine intravenously, as this causes clinically significant hypotension requiring cardiovascular support 5

Transfer to Specialized Centers

Transfer immediately to high-volume centers (>35 SAH cases per year) with experienced cerebrovascular surgeons, endovascular specialists, and multidisciplinary neurocritical care services. 4, 2, 3, 6

Management of Acute Hydrocephalus

Treat acute symptomatic hydrocephalus with urgent cerebrospinal fluid diversion via external ventricular drainage or lumbar drainage, depending on clinical scenario. 4, 1, 3

• Acute hydrocephalus occurs in 15-87% of patients 1
• Use standardized EVD bundle protocols 2
• Do not wean external ventricular drainage over >24 hours, as this does not reduce need for permanent shunting 1

Prevention and Management of Delayed Cerebral Ischemia

Maintain euvolemia and normal circulating blood volume; avoid prophylactic hypervolemia and hemodynamic augmentation ("triple-H therapy"). 4, 1, 3

• Critical pitfall: Prophylactic hypervolemia does not improve outcomes and may cause harm 1, 2, 3

For symptomatic delayed cerebral ischemia, induce hypertension while maintaining euvolemia, unless baseline BP is already elevated or cardiac status precludes it. 4, 1, 3

• This approach reduces progression and severity of delayed cerebral ischemia 1
• Cerebral angioplasty and/or selective intra-arterial vasodilator therapy may be reasonable after, together with, or in place of induced hypertension 4

Antifibrinolytic Therapy

Short-term antifibrinolytic therapy (<72 hours) with tranexamic acid or aminocaproic acid may be considered only when aneurysm obliteration is unavoidably delayed, the patient has high rebleeding risk, and no contraindications exist. 2

• The 2023 ULTRA trial showed tranexamic acid does not significantly lower rebleeding rates nor improve functional outcomes when aneurysms are secured early 2
• Antifibrinolytics increase risk of deep vein thrombosis 2
• Neither agent is FDA-approved for SAH 2

Medications to Avoid

Do not use routine statin therapy or intravenous magnesium for vasospasm prophylaxis. 1

• Aspirin, enoxaparin, and tirilazad have been shown ineffective 1
• Withhold aspirin and other antiplatelet agents until after the aneurysm is secured 2

Additional Supportive Care

Admit to specialized neurocritical care unit with evidence-based protocols and frequent neurological assessments. 1, 3

• Implement standardized ICU care bundles for mechanical ventilation when required (>24 hours) to reduce duration of ventilation and hospital-acquired pneumonia 3
• Initiate venous thromboembolism prophylaxis once aneurysm is secured 1
• Early identification and targeted treatment of heparin-induced thrombocytopenia and deep venous thrombosis are recommended 4, 3

Control fever aggressively to target normothermia using standard or advanced temperature modulating systems. 3

Manage glucose carefully with strict avoidance of hypoglycemia. 3

Consider packed red blood cell transfusion to treat anemia in patients at risk of cerebral ischemia, though transfusions have been associated with worse outcomes in some series. 3

Airway Management When Required

Use rapid-sequence intubation with pre-oxygenation, pharmacological blunting of reflex dysrhythmia, and careful avoidance of blood pressure fluctuations 4, 2

Follow-Up Imaging and Long-Term Management

Obtain immediate post-treatment cerebrovascular imaging to identify aneurysm remnants or recurrence. 4

Perform delayed follow-up vascular imaging at 6 and 18 months; strongly consider retreatment (repeat coiling or microsurgical clipping) if there is a clinically significant growing remnant. 4, 1

Target systolic blood pressure <160 mmHg in the chronic phase to prevent aneurysm recurrence. 1

Rehabilitation and Long-Term Outcomes

Refer all survivors for comprehensive multidisciplinary evaluation including cognitive, behavioral, and psychosocial assessments using validated screening tools. 1, 3

• Physical, cognitive, behavioral, and quality of life deficits are common and can persist long-term 1
• Early identification of mood disorders allows for interventions that improve long-term outcomes 1