acute ischaemic stroke
Contents
Time-critical emergency. Thrombolysis (TNK 0.25 mg/kg or alteplase 0.9 mg/kg) within 4.5 h of onset → EVT for large vessel occlusion up to 24 h with imaging selection. Pre-lysis BP <185/110, post-lysis/post-EVT BP <180/105 for 24 h. No antiplatelets for 24 h post-TNK, repeat CT before starting ASA.
- NIHSS on arrival → repeat q1h × 6 h, then q2h × 18 h
- STAT non-contrast CT + CTA arch-to-vertex (add CT perfusion if >6 h or wake-up stroke)
- blood work: glucose, CBC, INR/aPTT, electrolytes, creatinine, troponin, lipid panel, HbA1c — do not delay imaging for labs
- fingerstick glucose → treat hypoglycaemia immediately; insulin sliding scale targeting 7.8–10 mmol/L
- supplemental O₂ to maintain SpO₂ >94%
- if thrombolysis-eligible (≤4.5 h): BP <185/110 → TNK 0.25 mg/kg IV bolus (or alteplase 0.9 mg/kg) → BP <180/105 × 24 h
- if LVO on CTA → thrombectomy pathway (in-house or transfer) → EVT up to 24 h with perfusion selection → BP ≤180/105 × 24 h
- if no thrombolysis or EVT candidate: treat BP only if >220/120 → reduce ~15% over 24 h
- if thrombolysed: no antiplatelets × 24 h → CT head to exclude haemorrhage → then ASA 160 mg load
- if not thrombolysed: ASA 160 mg loading dose immediately
- minor stroke (NIHSS ≤3) or high-risk TIA, non-cardioembolic → DAPT: ASA + clopidogrel × 21 days
- statin (atorvastatin 40–80 mg) within 24 h → target LDL <1.8 mmol/L
- 12-lead ECG
- telemetry × 48 h minimum → if cryptogenic, arrange prolonged cardiac monitoring (≥14 days) → see Cryptogenic and Young Stroke
- TTE if cardioembolic source suspected
- if AF detected → plan DOAC with timing based on infarct size; do not anticoagulate ESUS empirically
- NPO until dysphagia screen (validated tool, within 24 h)
- oral hygiene protocol to reduce aspiration pneumonia risk
- temperature monitoring → treat fever aggressively
- DVT prophylaxis: pneumatic compression devices day 1 → pharmacological when safe
- mobilisation assessment within 24–48 h (avoid very early high-dose mobilisation per AVERT)
- multidisciplinary rehabilitation referral (PT/OT/SLP) within 24–48 h
- neurological deterioration → STAT CT → malignant MCA oedema or cerebellar mass effect → neurosurgery for decompression or EVD
thrombolysis
| alteplase | tenecteplase | |
|---|---|---|
| dose | 0.9 mg/kg (max 90 mg): 10% bolus over 1 min, 90% infusion over 60 min | 0.25 mg/kg (max 25 mg): single IV bolus over 5 s |
| window | ≤4.5 h from onset/last known well | ≤4.5 h from onset/last known well |
| advantage | established evidence base | simpler dosing, single bolus, non-inferior (AcT (2022)) |
BP must be <185/110 before lysis. Maintain <180/105 for 24 h after.
Any decline in consciousness, new headache, or neurological worsening → stop infusion (if running) → STAT CT head → draw CBC, INR, fibrinogen → consider cryoprecipitate or fibrinogen concentrate + tranexamic acid. Avoid PCC, platelets, and factor VIIa.
endovascular thrombectomy
Eligible if all four criteria met:
- Patient — age ≥18, baseline functional independence
- Symptoms — disabling deficit (NIHSS >5), last known well ≤24 h
- Occlusion — intracranial ICA, M1 MCA, or basilar on CTA
- Parenchyma — ASPECTS ≥6 (small core) or 3–5 (moderate core, selected patients)
≤6 h: CTA sufficient for selection. >6–24 h: requires CT perfusion or multiphase CTA to demonstrate salvageable tissue (DAWN (2018), DEFUSE 3 (2018)).
Procedural sedation preferred over GA unless airway compromise or severe agitation.
EVT does not preclude thrombolysis — give TNK/alteplase first if within window, proceed to angiography.
first 24 hours post-TNK
| time | action |
|---|---|
| 0–1 h | neuro checks q15 min, BP q15 min, keep <180/105 |
| 1–6 h | neuro checks q1h, BP q1h |
| 6–24 h | neuro checks q2h, BP q2h |
| 24 h | repeat CT head → if no haemorrhage → start ASA 160 mg |
| 24 h onward | transition to oral antihypertensives if needed, start secondary prevention |
Antiplatelet therapy delayed until 24-h CT excludes haemorrhagic transformation. This applies to both ASA and heparin (including DVT prophylaxis doses).
blood pressure targets
| scenario | target |
|---|---|
| pre-lysis | <185/110 |
| post-lysis (24 h) | <180/105 |
| no thrombolysis, moderate HTN (<220 systolic) | do not treat routinely |
| no thrombolysis, extreme HTN (>220/120) | reduce ~15% over 24 h (not >25%) |
| post-EVT (during and 24 h after) | ≤180/105; emerging evidence suggests avoiding SBP <140 |
acute antithrombotic therapy
No thrombolysis given:
- ASA ≥160 mg loading dose immediately → 81 mg daily
- Alternative: clopidogrel 300–600 mg load → 75 mg daily
Post-thrombolysis:
- No antiplatelets × 24 h → CT to exclude bleed → then ASA 81 mg daily
DAPT for minor stroke / high-risk TIA (NIHSS 0–3, non-cardioembolic):
- ASA 162 mg + clopidogrel 300–600 mg load → ASA 81 mg + clopidogrel 75 mg daily × 21 days (CHANCE (2013), POINT (2018))
- Alternative (AHA/ESO, not CSBPR): ASA + ticagrelor 180 mg load → 90 mg BD × 30 days
- Do not extend DAPT beyond 21–30 days → bleeding risk outweighs benefit
anticoagulation for AF-related stroke
Timing by stroke severity — start DOACs over Warfarin:
| stroke severity | start anticoagulation |
|---|---|
| TIA, no infarct on imaging | within 24 h |
| minor stroke / small infarct | day 3 |
| moderate stroke / moderate infarct | day 6–7 |
| severe stroke / large infarct | day 12–14 |
Bridge with ASA until anticoagulation started.
traps
- Clock starts at last known well, not symptom discovery — a wake-up stroke is not automatically excluded (use perfusion imaging)
- TNK and alteplase have the same time window but TNK is a single bolus → logistically simpler, especially for drip-and-ship transfers
- Do not chase mild hypertension pre-lysis — aggressive lowering may worsen ischaemia. Only treat if >185/110
- ASPECTS is scored on non-contrast CT; ≥6 supports EVT, but 3–5 may still benefit in selected patients with favourable perfusion
- Orolingual angioedema post-alteplase (1–5%) → stop infusion, H1 + H2 blockers, consider epinephrine
- Very early mobilisation (<24 h, high intensity) may worsen outcomes (AVERT) — early but gentle mobilisation is reasonable
- Do not delay lysis for blood work unless on anticoagulants or clinical concern for coagulopathy — a normal-appearing patient with known medication list can be lysed before results return