In an 11‑year‑old with a thalamic‑cerebellopontine infarct and hemorrhagic conversion, when can low‑dose aspirin (acetylsalicylic acid) be started, should mannitol be continued, and what is the best next step given limited resources (e.g., repeat CT (computed tomography) and basic labs)?

Management of Aspirin Initiation and Mannitol in Pediatric Hemorrhagic Stroke

When to Start Aspirin After Hemorrhagic Conversion

In an 11-year-old with ischemic stroke and hemorrhagic conversion, delay aspirin until repeat CT confirms hemorrhage stability—typically 7–14 days after the bleed—and only after intracranial pressure is controlled and the child is neurologically stable. 1

Timing Algorithm for Aspirin Initiation

• Immediate contraindication: Do not start aspirin in the presence of active intracranial hemorrhage or hemorrhagic transformation until imaging confirms stability 1
• Repeat CT scan: Obtain a follow-up non-contrast head CT at 7–14 days post-hemorrhage to document that the hemorrhage is not expanding and that there is no new bleeding 1
• Clinical stability required: The patient must be afebrile, hemodynamically stable, and show no signs of increasing intracranial pressure (no worsening headache, vomiting, altered consciousness, or new focal deficits) 1
• Loading dose when safe: Once hemorrhage is stable on repeat imaging and ICP is controlled, administer aspirin 160 mg as a single loading dose, then continue 81 mg daily indefinitely 1

Pediatric-Specific Aspirin Dosing

• For children ≥11 years with ischemic stroke: Use adult dosing of 160 mg loading dose followed by 81 mg daily after hemorrhagic transformation is excluded 1, 2
• Minimum duration: Continue aspirin for at least 2 years once dissection and cardioembolic causes are ruled out 2
• Safety monitoring: Ensure annual influenza vaccination because aspirin increases Reye syndrome risk during influenza or varicella infection 2, 3

Mannitol Continuation Decision

Discontinue mannitol once intracranial pressure normalizes and clinical examination stabilizes, typically within 3–7 days; continuing mannitol beyond this window offers no proven benefit and risks renal toxicity and electrolyte derangement. 4, 5

Evidence-Based Mannitol Strategy

• Mannitol reduces ICP proportionally to baseline elevation: For every 1 mmHg increase in baseline ICP, mannitol reduces ICP by approximately 0.64 mmHg 5
• Dose-dependent effect only during active ICP elevation: Once ICP reaches a stable lower level, additional mannitol does not provide further reduction—this is termed "mannitol saturation" 6
• No mortality benefit in hemorrhagic stroke: A propensity-matched analysis of 2839 patients showed mannitol did not improve 90-day death or disability outcomes in intracerebral hemorrhage (OR 0.90,95% CI 0.75–1.09) 4
• Possible benefit in larger hemorrhages: Patients with hematomas ≥15 mL showed a trend toward better outcomes with mannitol (OR 0.52,95% CI 0.35–0.78), but this was not consistent across other cutoff points 4

Practical Mannitol Tapering Protocol

• Monitor ICP if available: If ICP monitoring is in place, taper mannitol when ICP remains <20 mmHg for 24–48 hours 5, 6
• Clinical monitoring in resource-limited settings: Without ICP monitoring, assess for signs of herniation (pupillary changes, posturing, irregular respirations, bradycardia) and taper mannitol when the patient shows sustained neurological improvement for 48–72 hours 1
• Typical duration: Most patients require mannitol for 3–5 days; prolonged use beyond 7 days is rarely justified and increases risk of renal failure and electrolyte imbalance 6

Best Next Steps in Resource-Limited Settings

Obtain a repeat non-contrast head CT at 7–10 days to assess hemorrhage stability and guide aspirin initiation; meanwhile, continue supportive care with head-of-bed elevation to 30 degrees, maintain normothermia, and ensure adequate hydration. 1

Priority Interventions Without Advanced Monitoring

1. Repeat CT timing: Schedule follow-up CT at 7–10 days post-hemorrhage; this single scan is the minimum required to safely restart antiplatelet therapy 1
2. Basic laboratory monitoring: Check serum sodium, potassium, creatinine, and osmolality every 2–3 days while on mannitol to detect electrolyte derangements and renal dysfunction 6
3. Clinical neurological checks: Perform Glasgow Coma Scale and pupillary examination every 4 hours; any decline mandates immediate CT if available 1
4. Blood pressure management: Maintain systolic BP <140 mmHg in the acute phase to minimize hematoma expansion risk, using oral agents (e.g., amlodipine, labetalol) if IV agents are unavailable 4

Hemorrhagic Transformation Risk Stratification

• Mild stroke (NIHSS ≤3): Lower risk of symptomatic hemorrhagic transformation; aspirin may be considered at 3–5 days if repeat CT shows stable small hemorrhage 1
• Moderate stroke (NIHSS 4–15): Wait 6–8 days before restarting aspirin, and only after repeat imaging excludes expansion 1
• Severe stroke (NIHSS >15): Delay aspirin for 12–14 days and obtain repeat brain imaging before any antiplatelet therapy 1

Critical Pitfalls to Avoid

• Never start aspirin based solely on clinical improvement without repeat imaging: Hemorrhagic transformation can be clinically silent, and aspirin may precipitate catastrophic expansion 1, 7
• Do not combine aspirin with anticoagulation in the first 2 weeks: The combination dramatically increases symptomatic intracranial hemorrhage risk (meta-analysis showed significant increase when parenteral anticoagulants given within 7–14 days of stroke) 1, 7
• Avoid ibuprofen if aspirin is started: Ibuprofen completely antagonizes aspirin's irreversible platelet inhibition and should never be co-administered 2, 3
• Do not continue mannitol "just in case": Prolonged mannitol without documented elevated ICP causes renal failure, rebound cerebral edema, and electrolyte chaos without proven benefit 4, 6, 8
• Recognize that adult stroke guidelines apply to adolescents: An 11-year-old with arterial ischemic stroke should be managed with adult stroke protocols for antiplatelet therapy, not pediatric Kawasaki disease dosing 1, 2