7.1 Acute Ischemic Stroke & Intracerebral Hemorrhage

7.1 Acute Ischemic Stroke & Intracerebral Hemorrhage

Clinical Scenario: A 68-year-old male presents 75 minutes after acute onset of right hemiplegia, facial droop, and global aphasia. Vital signs: BP 198/112 mmHg, HR 88 bpm (atrial fibrillation), RR 18 breaths/min, SpO2 98%, fingerstick glucose 132 mg/dL. Baseline NIHSS is 19. Emergent non-contrast head CT excludes hemorrhage (ASPECTS 10). CT angiography confirms an acute left MCA M1 segment occlusion.

Hyperacute Evaluation & NIHSS Stratification

Emergency triage salvages ischemic penumbra ("time is brain"). Hyperacute priorities:

1. ABCs & Glucose: Assure oxygenation (SpO2 ≥ 94%) and exclude hypoglycemia (<60 mg/dL), the primary stroke mimic.
2. Emergent Non-Contrast Head CT (NCCT): Differentiates ischemic stroke from intracerebral hemorrhage (ICH) or subarachnoid hemorrhage (SAH).
3. NIHSS Quantification (0–42): Mild (1–4), moderate (5–15), moderate-to-severe (16–20), and severe (21–42); scores >25 reflect massive hemispheric infarction.

Intravenous Thrombolysis: Alteplase vs. Tenecteplase

Thrombolytics activate plasminogen to dissolve fibrin clots:

• Alteplase (rt-PA): 0.9 mg/kg (maximum 90 mg); administer 10% as IV bolus over 1 minute, and infuse remaining 90% over 60 minutes via infusion pump.
• Tenecteplase (TNK): Genetically modified tPA with greater fibrin specificity. Dosed at 0.25 mg/kg single rapid IV bolus over 5–10 seconds (maximum 25 mg). Preferred for rapid delivery prior to thrombectomy.
• Treatment Window: Treat eligible disabling deficits as soon as possible within 4.5 hours, regardless of NIHSS. Age >80 or prior stroke plus diabetes is not an automatic exclusion. Selected unknown-onset or 4.5–9-hour presentations require advanced imaging selection.
• Complication Surveillance: Monitor closely for orolingual angioedema (seen in up to 5% of patients, especially with ACE inhibitor therapy), which requires prompt administration of IV methylprednisolone, diphenhydramine, famotidine, and airway vigilance.

Endovascular Thrombectomy (EVT) & Penumbral Imaging

EVT achieves mechanical recanalization in large vessel occlusion (LVO):

• ICA/M1 Occlusion: For NIHSS ≥6 and prestroke mRS 0–1, EVT is recommended within 0–6 hours with ASPECTS 3–10, or 6–24 hours with ASPECTS ≥6. Selected patients <80 years, without significant mass effect, also qualify at 6–24 hours with ASPECTS 3–5. Current selection extends beyond DAWN/DEFUSE-3 mismatch criteria.
• Basilar Occlusion: EVT within 24 hours is recommended with NIHSS ≥10, prestroke mRS 0–1 and PC-ASPECTS ≥6.
• Bridging Strategy: Deliver IV thrombolysis immediately when eligible; proceed directly to EVT without pausing to assess thrombolytic response.
• Procedural Care: EVT achieves successful reperfusion (mTICI score 2b or 3). Post-procedure arterial sheath monitoring is critical to prevent groin hematoma or retroperitoneal hemorrhage.

Blood Pressure Management in Acute Stroke

• Thrombolysis Candidates:
  • Pre-infusion Goal: Lower BP to <185/110 mmHg before starting thrombolytic.
  • Post-infusion Maintenance: Maintain BP <180/105 mmHg for 24 hours to prevent reperfusion hemorrhage.
  • First-Line Agents: IV nicardipine (5–15 mg/hr), clevidipine (1–21 mg/hr), or labetalol (10–20 mg IV boluses).
  • Monitoring: Neuro checks and BP every 15 min for 2 hours, every 30 min for 6 hours, then hourly for 16 hours. Stop infusion and obtain stat head CT if severe headache, hypertension, or deterioration occurs.
• EVT: Without prior IVT, maintain BP ≤185/110 before EVT and ≤180/105 during and for 24 hours afterward. Avoid intensive SBP lowering below 140 after successful reperfusion.
• No Reperfusion: If neither IVT nor EVT is given, avoid routine early lowering below 220/120. Above this, individualize a cautious initial reduction of about 15%. Treat urgent comorbid indications (e.g., aortic dissection, ACS or acute heart failure) without waiting for that threshold.

Spontaneous Intracerebral Hemorrhage (ICH) & Scoring

Primary ICH stems from deep hypertensive arteriolopathy or lobar amyloid angiopathy:

• Diagnostic NCCT: Identifies parenchymal hematoma, midline shift, and intraventricular extension (IVH).
• ICH Volume ($ABC/2$ formula): $(A \times B \times C) / 2$, where $A$ and $B$ are perpendicular diameters (cm) and $C$ is slice thickness $\times$ positive slices.
• The ICH Score (0–6 points): Predicts 30-day mortality:
  • GCS: 3–4 (2 pts), 5–12 (1 pt), 13–15 (0 pts).
  • ICH Volume: ≥ 30 cm³ (1 pt), < 30 cm³ (0 pts).
  • IVH: Present (1 pt), Absent (0 pts).
  • Infratentorial Origin: Yes (1 pt), No (0 pts).
  • Age: ≥ 80 years (1 pt), < 80 years (0 pts).
  • Mortality by Score: 0 (0%), 1 (13%), 2 (26%), 3 (72%), 4 (97%), 5–6 (100%).

Acute SBP Lowering & Anticoagulant Reversal in ICH

• SBP Target: For mild/moderate ICH with presenting SBP 150–220, target 140 mmHg, maintaining 130–150 with smooth titration and reaching the target within one hour when feasible. Avoid SBP <130. For large/severe ICH or required surgical decompression, individualize BP to preserve perfusion; intensive lowering has uncertain safety and benefit.
• Urgent Coagulation Reversal:
  • Warfarin (VKA): 4-Factor PCC (25–50 units/kg IV) plus IV Vitamin K 10 mg slow infusion. FFP is second-line due to volume overload and delayed correction.
  • Dabigatran: Idarucizumab (Praxbind) 5 g IV (two 2.5 g doses).
  • Factor Xa Inhibitors (Apixaban, Rivaroxaban): 4-Factor PCC 50 units/kg IV may be used under the emergency reversal protocol. US commercial sales of andexanet ended December 22, 2025 after FDA safety review.
  • Heparin / LMWH: Protamine sulfate (1 mg per 100 units heparin in past 2–3 hr, max 50 mg; 1 mg per 1 mg enoxaparin within 8 hr).
• Neurosurgical Indications: Cerebellar ICH with neurological deterioration, brainstem compression, obstructive hydrocephalus or volume ≥15 mL requires urgent hematoma evacuation, with or without EVD, to reduce mortality. Do not use a diameter cutoff to delay surgery for these indications; EVD alone does not relieve the posterior-fossa mass.