A 72-year-old client is brought to the emergency department … | MyMerci
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Medical EmergenciesPA
Question
A 72-year-old client is brought to the emergency department by family who report that the client developed sudden left-sided weakness and slurred speech approximately 2 hours ago. The CT head shows no hemorrhage and the NIH Stroke Scale score is 14. Which assessment is most critical to confirm before IV tissue plasminogen activator is administered?
1Exact time the client was last known well✓ Correct answer
2Family history of bleeding disorders
312-lead ECG findings
4Blood glucose level
Explanation
Time of last known well is the single most critical determinant of tPA eligibility for ischemic stroke. AHA/ASA standard: IV alteplase or tenecteplase within 4.5 hours of last known well in eligible candidates. Other parameters (blood glucose, ECG, bleeding history) are also assessed but cannot establish treatment eligibility unless the time window is first confirmed.
Clinical Judgment Acute ischemic stroke management is gated by last known well time. tPA window: 4.5 hours from last known well in eligible clients (NINDS / ECASS-III). Without the time window, no thrombolytic decision can be made regardless of NIH score, glucose, or ECG.
Memory Tip Stroke FAST + last known well — first question always asked
KR vs US AHA/ASA 4.5-hour window is the global standard. Korean stroke center registries (CRCS-K) follow the same window; thrombectomy now extended up to 24 hours in selected large vessel occlusion cases.
Clinical scenario
Clinical Practice Guide 2019 AHA/ASA Stroke Guideline: IV alteplase 0.9 mg/kg (max 90 mg) over 1 hour with 10% bolus over 1 minute, or tenecteplase 0.25 mg/kg bolus, within 4.5 hours of last known well. Mechanical thrombectomy for large vessel occlusion within 6-24 hours in select clients. Maintain BP <185/110 before tPA.
Caution Wake-up strokes use the time the client was last seen normal as the time-last-known-well. Do not assume tPA-ineligibility — modern MRI-based imaging may extend the window in select cases.
Key concepts
Last known well — Last point in time when the client was confirmed without stroke symptoms. Defines the start of the treatment window for thrombolysis. Wake-up strokes use the time the client was last observed at neurologic baseline.
tPA (alteplase) — Tissue plasminogen activator. Thrombolytic that converts plasminogen to plasmin and lyses fibrin clots. Used IV for ischemic stroke within 4.5 hours and STEMI within 12 hours when PCI unavailable. Major risk: intracranial hemorrhage.
NIH Stroke Scale — Standardized 15-item neurologic assessment scoring 0-42. Score 5 or higher generally warrants reperfusion consideration; score >25 may relatively contraindicate IV tPA due to large infarct burden.