Emergency Medicine Field Card · Reperfusion

Acute Ischemic Stroke First Hour

Find the clock. Exclude hemorrhage. Decide thrombolysis and thrombectomy in parallel. Treat disabling symptoms, not the NIHSS number alone.

Updated July 2026 Basis 2026 AHA/ASA Read time 90 sec
4.5 h
standard IV thrombolysis window
24 h
selected LVO thrombectomy window
15%
initial BP reduction when treatment is required without reperfusion
First minutes

Run the code in parallel

  • Document last known well, symptom discovery, and wake-up timing
  • NIHSS plus a disabling-deficit assessment
  • Fingerstick glucose and noncontrast head CT immediately
  • CTA head/neck for EVT candidates while IVT eligibility is reviewed
  • ECG, troponin, CBC, and coagulation tests must not create avoidable delay

Only glucose must be known before IVT in every patient. Await coagulation results if anticoagulant use or coagulopathy is suspected.

Disabling vs nondisabling

NIHSS is not the decision

Disabling: aphasia, meaningful weakness, hemianopia, neglect, or loss of usual function. Treat if eligible.

Nondisabling: IVT has no demonstrated net benefit. Use antiplatelet therapy, including short-course DAPT when eligible, per protocol.

Reperfusion path

Use the clock, then the tissue

0–4.5 hours

Disabling deficit

After noncontrast CT, give alteplase or tenecteplase if eligible. No advanced imaging is required.

Unknown or 4.5–9 hours

Image-select IVT

MRI DWI-FLAIR or CT/MR perfusion mismatch can select candidates. Apply protocol timing.

0–24 hours

Find the LVO

Use CTA/MRA and imaging selection. Large core is not an automatic exclusion. Call early.

Clinical Pearl

Do not make IV thrombolysis wait for CTA.

Within 4.5 hours, give eligible IVT and continue toward thrombectomy. Do not wait to see whether the deficit improves.

Thrombolysis

Two endorsed options

ALTEPLASE 0.9 mg/kg IV · MAX 90 mg
10% bolus over 1 min, then 90% over 60 min
TENECTEPLASE 0.25 mg/kg IV · MAX 25 mg
Single bolus over 5 sec

AHA/ASA endorses either agent through 4.5 hours. The US TNKase label specifies treatment within 3 hours and weight-banded dosing. Follow local policy.

Blood pressure

Match the target to reperfusion

<185/110
before IV thrombolysis
<180/105
for 24 h after IVT

Examples: labetalol 10–20 mg IV over 1–2 min, repeat once; or nicardipine 5 mg/h IV, increase 2.5 mg/h every 5–15 min to max 15 mg/h.

No reperfusion: without a hypertensive emergency, avoid routine lowering below 220/120. At or above 220/120, reduce about 15% initially.

15% = 10% + 5%
SBP 220: 22 + 11 = 33 → target about 187
Safety screen

Stop and verify

  • Intracranial hemorrhage, active internal bleeding, or uncontrolled BP
  • Platelets <100,000/µL, INR >1.7, or elevated aPTT from heparin
  • Recent DOAC without a reassuring drug-specific assay; recent therapeutic LMWH
  • Recent intracranial/intraspinal surgery or serious head trauma
  • Suspected aortic dissection or another dangerous alternate diagnosis

Not exhaustive. Recent major noncranial surgery is case-specific, not a universal absolute exclusion. Use the institutional IVT checklist.

Thrombectomy

Expand, do not exclude reflexively

  • LVO, disabling deficit, and favorable clinical/imaging selection
  • Some patients with a large ischemic core still benefit
  • For basilar artery occlusion within 24 h and NIHSS ≥10, EVT is strongly recommended
  • Give eligible IVT without delaying transfer or arterial access
After thrombolysis

Protect the first 24 hours

  • Neuro/BP checks q15 min for 2 h, q30 min for 6 h, then hourly to 24 h
  • Avoid antiplatelet or anticoagulant for 24 h unless a compelling indication is reviewed with the stroke team
  • Repeat CT or MRI at 24 h before antithrombotic therapy
  • Any worsening: stop alteplase if infusing, obtain urgent CT, and activate the hemorrhage protocol
  • Avoid intensive SBP lowering to <140, including after successful EVT