First Things First (assess for & treat the following):

Myocardial infarction (MI)

• Appropriately used thrombolytics will:
  • Limit infarct size
  • Improve left ventricular function
  • Reduce mortality
  • Once MI confirmed, other medical diagnostics and treatment should not delay implementation of reperfusion strategy
• Most benefit (ST-elevation MI, if percutaneous coronary intervention [PCI] not available within 90 minutes of first medical contact) if < 3 hrs from symptom onset
  • Shorter time to reperfusion leads to better outcome
  • Proven value up to 12 hrs from symptom onset
  • 12-24 hrs from symptom, fibrinlysis may be indicated if signs of continuing ischemia are present
• Primary PCI
  • Most rapid & reliable for restoring coronary flow
  • Use instead of thrombolytics if available within 90 minutes of symptom debut

Pulmonary embolism (PE)

• Thrombolytics appropriate for confirmed massive PE only (PE with systolic blood pressure < 90 mmHg)
• Hemodynamic instability: hypotension with right ventricular strain
  • Modest, careful volume resuscitation: ~1 L, cautious vasoactive/inotropic support if progressive deterioration
• Respiratory insufficiency: hypoxemia or respiratory distress
  • Oxygen therapy
  • Intubate for refractory hypoxemia or frank respiratory distress.
• Diagnostic testing in unstable patients
  • CT angiogram to confirm massive PE
  • Consider supporting tests available in ICU/ER for decision to anticoagulate if CT not available.
    • Echocardiography
    • Lower extremity duplex ultrasound
    • CXR
    • EKG
    • D-dimer; PaO2

Stroke (acute ischemic stroke)

• Time is critical (for patients eligible for tPA)
  • < 3 hrs from clearly defined symptom onset to IV thrombolytic administration
    • Decreased risk of death
    • Improved neuro outcome
  • 3-4.5 hrs from symptom onset, no indication for IV thrombolytics
  • >4.5 hours, strong recommendation against use of thrombolytics for ischemic stroke
  • No thrombolytics for patients with extensive stroke (>1/3 MCA territory) or clear hypodensity on CT
    • Streptokinase associated with bleeding complications in ischemic stroke, contraindicated
      • Intra-arterial thrombolytics suggested if available for middle cerebral artery occlusion, (within 6 hrs from symptom onset)
      • For confirmed acute basilar artery occlusion, IV or intra-arterial thrombolysis may be useful if available
• Consideration for thrombolytics must begin in ER.
  • Critical pathways streamline process.