Initial assessment and triage

Initial assessment and triage

Initial assessment and triage

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Initial Assessment - The First 10 Minutes

  • ABCs & Vitals: Immediate stabilization, focused history, and physical exam.
  • Initial Setup: IV access (2 large-bore), cardiac monitor, pulse oximetry.
  • Oxygen: Only if O₂ saturation < 90% or in respiratory distress.
  • Medications (Concurrent):
    • Aspirin: 325 mg (chewed) immediately.
    • Nitroglycerin (sublingual): For active pain. ⚠️ Caution with hypotension, bradycardia, or recent PDE-5 inhibitor use.
    • Morphine: For pain refractory to nitroglycerin.

⭐ A 12-lead ECG must be obtained and interpreted within 10 minutes of arrival. If initial ECG is non-diagnostic but suspicion is high, consider posterior leads (V7-V9).

12-lead ECG showing acute anterior STEMI

ECG Interpretation - Reading the Lines

  • Primary Goal: Identify ST-elevation MI (STEMI) for emergent reperfusion.
  • STEMI Criteria: New ST elevation at the J-point in ≥2 contiguous leads.
    • ≥1 mm in most leads.
    • In leads V2-V3: ≥2 mm in men ≥40y, ≥2.5 mm in men <40y, or ≥1.5 mm in women.
  • NSTEMI/Ischemia: New horizontal or downsloping ST depression ≥0.5 mm or T-wave inversion ≥1 mm.
  • Pathologic Q-waves: Indicate prior MI; >0.04s wide & >25% of R-wave height.

⭐ A new or presumed new Left Bundle Branch Block (LBBB) in a patient with ischemic chest pain is considered a STEMI equivalent.

ECG: Inferior MI with ST elevation and reciprocal changes

Cardiac Biomarkers - Chemical Footprints

  • Troponins (cTnI, cTnT): The gold standard for MI diagnosis due to high sensitivity and specificity.
    • Rise: 2-4 hrs
    • Peak: 24-48 hrs
    • Duration: 7-10 days
    • 📌 Troponin lasts up to Ten days.
  • Creatine Kinase-MB (CK-MB):
    • Rise: 4-6 hrs
    • Peak: 12-24 hrs
    • Baseline: 48-72 hrs
    • Useful for detecting reinfarction.

Cardiac biomarker temporal profile after MI

⭐ High-sensitivity troponin (hs-cTn) can rule out MI faster (e.g., in a 0/1-hour algorithm).

Immediate Triage - The MONA-BASH Protocol

📌 MONA-BASH is a classic mnemonic, though treatment order varies. Aspirin first!

  • Aspirin: 162-325 mg chewed immediately to inhibit platelet aggregation. Reduces mortality.
  • Oxygen: Supplemental O₂ only if saturation is <90% or in respiratory distress.
  • Nitroglycerin: Sublingual/IV. Vasodilator; reduces preload and pain.
    • Contraindicated in hypotension (SBP <90 mmHg), recent PDE-5 inhibitor use, or right ventricular infarction.
  • Morphine: IV for refractory chest pain despite nitrates. Also reduces preload.
  • Beta-Blockers: e.g., Metoprolol. Reduces O₂ demand and arrhythmias. Start within 24h if no signs of heart failure/shock.
  • ACE Inhibitors: Start within 24h, especially in patients with anterior MI, heart failure, or EF <40%.
  • Statin: High-intensity (e.g., Atorvastatin 80 mg) initiated ASAP, regardless of baseline cholesterol.
  • Heparin (UFH or LMWH): Anticoagulation to prevent further thrombus formation.

⭐ Beta-blockers are one of the few initial therapies (along with Aspirin and reperfusion) that have a proven mortality benefit in acute MI.

  • Initial management includes ABCs, IV access, cardiac monitoring, and a 12-lead ECG within 10 minutes.
  • Administer chewable aspirin (162-325 mg) immediately to all patients without contraindications.
  • Supplemental O₂ is only for hypoxemia (SaO₂ <90%) or respiratory distress.
  • Nitroglycerin for chest pain is contraindicated in right ventricular infarction, severe aortic stenosis, or recent PDE-5 inhibitor use.
  • Morphine is a second-line analgesic for pain refractory to nitrates.

Practice Questions: Initial assessment and triage

Test your understanding with these related questions

A 66-year-old man comes to the emergency department because of a 1-day history of chest pain, palpitations, and dyspnea on exertion. He had a similar episode 3 days ago and was diagnosed with an inferior wall myocardial infarction. He was admitted and a percutaneous transluminal coronary angioplasty was successfully done that day. A fractional flow reserve test during the procedure showed complete resolution of the stenosis. Laboratory tests including serum glucose, lipids, and blood count were within normal limits. He was discharged the day after the procedure on a drug regimen of aspirin, simvastatin, and isosorbide dinitrate. At the time of discharge, he had no chest pain or dyspnea. Presently, his vitals are normal and ECG at rest shows new T-wave inversion. Which of the following is the most reliable test for rapidly establishing the diagnosis in this patient?

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Flashcards: Initial assessment and triage

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Which major medical insurance plan limits patients to a network of doctors, specialists, and hospitals without requirement of referrals?_____

TAP TO REVEAL ANSWER

Which major medical insurance plan limits patients to a network of doctors, specialists, and hospitals without requirement of referrals?_____

Exclusive provider organization (EPO)

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