First Things First (assess & treat for the following)

• Stroke Definitions & Background Information

• Stroke = sudden brain dysfunction due to blood-vessel problem
• Stroke types
  • Acute ischemic stroke (AIS) 87% = low blood flow to a focal area of brain, usually caused by thromboembolism
  • Intracerebral hemorrhage (ICH) 10% = bleeding into brain due to nontraumatic vessel rupture
  • Subarachnoid hemorrhage (SAH) 3% = bleeding around brain due to nontraumatic vessel rupture
• Transient ischemic attack (TIA) = reversible brain dysfunction due to ischemia, typically lasting less than one hour (24-h limit is arbitrary and outdated) - i.e., this is an ischemic stroke without sequelae
• Penumbra = zone of reversible ischemia around core of irreversible infarction that is salvageable in the first few hours after ischemic stroke onset
• Etiologies of AIS and TIA
  • Large-artery disease (atherosclerosis)
  • Small-artery disease (lacunes)
  • Cardioembolism
  • Nonatherosclerotic vasculopathies (esp. arterial dissection)
  • Hypercoagulable states
  • Hypotension (causing watershed = border-zone infarctions)
• Epidemiology in U.S.
  • 795,000 strokes/year—610,000 first, 185,000 recurrent
  • Third leading cause of death among adults
  • A leading cause of long-term disability
  • 28% occur in people age <65
  • Costs $68.9 billion/year

• Initial Assessment Overview

• Before imaging
  • Identify witness, determine last time known without symptoms
  • Determine if shaking or staring at symptom onset to suggest seizure
  • Avoid lowering BP— increased BP helps perfuse penumbra of ischemic stroke
  • Avoid aspiration—keep head >30 degrees & 100% NPO
  • Maintain O2 saturation >92% with 2-4 L O2 if necessary
  • Determine fingerstick glucose—treat if <50 mg/dL
  • Avoid hyperglycemia—do not give glucose-containing or hypotonic solutions; maintain glucose 60-150 mg/dL
  • Infuse IV NS 50-75 cc/hr
  • Draw & send STAT pre-tPA labs: CBC w platelets, basic chemistries, PT/INR, aPTT, cardiac panel
  • Obtain 12-lead ECG
  • Obtain STAT noncontrast CT brain
• After imaging
  • Ischemic stroke—administer IV tPA if patient meets all criteria (see below), admit for etiologic evaluation, supportive care
  • TIA—admit (observation status) for rapid etiologic evaluation (see below)
  • ICH—admit for blood pressure management, supportive care
  • SAH—admit to ICU for coiling or clipping and supportive care