What is Acute Coronary Syndrome (ACS) Protocol

From the Guidelines

The Acute Coronary Syndrome (ACS) protocol involves immediate administration of aspirin, nitroglycerin, and morphine, followed by a 12-lead ECG, oxygen therapy, and additional medications such as P2Y12 inhibitors and anticoagulants, with the goal of quickly diagnosing and treating potentially life-threatening coronary events. The protocol is based on the clinical presentation of ACS, which can range from cardiac arrest to patients who are already pain-free at the time of presentation, with the leading symptom being acute chest discomfort described as pain, pressure, tightness, and burning 1.

Key Steps in the ACS Protocol

• Immediate administration of:
  • Aspirin (325 mg chewed)
  • Nitroglycerin (0.4 mg sublingual, repeated every 5 minutes up to 3 doses)
  • Morphine (2-4 mg IV) for pain relief if needed
• Obtain 12-lead ECG within 10 minutes of arrival to differentiate between patients with persistent ST-segment elevation and those without 1
• Start oxygen therapy if oxygen saturation is below 90%
• Administer additional medications:
  • P2Y12 inhibitor (e.g., clopidogrel 300-600 mg loading dose)
  • Anticoagulant (e.g., heparin or low molecular weight heparin)
• Perform rapid assessment for reperfusion therapy eligibility, with the mainstay of treatment for patients with ST-segment elevation being immediate reperfusion by primary percutaneous coronary intervention (PCI) or fibrinolytic therapy 1
• Initiate reperfusion therapy if indicated:
  • Primary PCI within 90 minutes for STEMI
  • Fibrinolysis within 30 minutes if PCI is not available
• Continuous cardiac monitoring and frequent vital sign checks to quickly diagnose and treat potentially life-threatening coronary events and prevent complications 1.

Importance of Early Diagnosis and Treatment

The ACS protocol aims to reduce myocardial damage and prevent complications by quickly restoring blood flow to the affected heart muscle. The combination of antiplatelet, anticoagulant, and reperfusion therapies works to achieve this goal, with the most recent guidelines emphasizing the importance of immediate reperfusion for patients with ST-segment elevation 1.

From the FDA Drug Label

Clopidogrel tablets are indicated to reduce the rate of myocardial infarction (MI) and stroke in patients with non–ST-segment elevation ACS (unstable angina [UA]/non–ST-elevation myocardial infarction [NSTEMI]), including patients who are to be managed medically and those who are to be managed with coronary revascularization In patients who need an antiplatelet effect within hours, initiate clopidogrel tablets with a single 300 mg oral loading dose and then continue at 75 mg once daily.

The Acute Coronary Syndrome (ACS) Protocol involves administering clopidogrel tablets with a single 300 mg oral loading dose, followed by 75 mg once daily, in conjunction with aspirin, to reduce the rate of myocardial infarction and stroke in patients with non–ST-segment elevation ACS, including those managed medically or with coronary revascularization 2.

• Key components of the protocol:
  • Single 300 mg oral loading dose of clopidogrel
  • 75 mg once daily maintenance dose of clopidogrel
  • Concomitant administration of aspirin
• Patient population: Patients with non–ST-segment elevation ACS, including unstable angina and non–ST-elevation myocardial infarction.

From the Research

Acute Coronary Syndrome (ACS) Protocol

The ACS protocol involves the administration of aspirin and other antithrombotic therapies to reduce morbidity and mortality in patients with ACS.

• The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy recommends immediate and daily oral aspirin for patients presenting with non-ST-segment elevation (NSTE) acute coronary syndrome (ACS) 3.
• The initial aspirin dose for ST-elevation myocardial infarction patients treated with fibrinolytic therapy is unclear, but studies suggest that an initial dose of 162 mg may be as effective as and perhaps safer than 325 mg 4.
• A high initial dose of aspirin is recommended in acute coronary syndromes, followed by a low dose of less than 100 mg for chronic prevention 5.
• Rectal administration of a 600-mg aspirin suppository provides sufficient levels of salicylic acid within 90 minutes to meet or exceed that of oral aspirin 6.
• Prehospital aspirin administration for ACS in the USA is inadequate, with only 45.4% of patients with suspected cardiac ischaemia receiving aspirin from EMS providers 7.

Aspirin Administration

Aspirin administration is a critical component of the ACS protocol.

• The recommended dose of aspirin for ACS patients is 75-162 mg per day 3, 5.
• The initial aspirin dose for ST-elevation myocardial infarction patients treated with fibrinolytic therapy may be 162 mg or 325 mg, but the optimal dose is unclear 4.
• Aspirin should be administered immediately and daily for patients presenting with NSTE ACS 3.
• Rectal administration of aspirin may be an alternative for patients who cannot take oral aspirin 6.

Patient Characteristics and Aspirin Administration

Patient characteristics, such as age, sex, and insurance status, may influence aspirin administration.

• Non-Hispanic black, Asian, and Hispanic patients have greater odds of aspirin administration by EMS compared to non-Hispanic white patients 7.
• Patients living in the Southern region of the USA and those with governmental insurance have lower odds of receiving aspirin 7.
• Age and sex are not associated with aspirin administration 7.