EMS Pharmacology - Aspirin (Acetylsalicylic Acid)

EMS Providers should have knowledge of aspirin administration including, amongst other things, its mechanism of action, the effect, and contraindications 

Here are key points to know:

Indications: Aspirin is commonly used in emergency situations to treat suspected heart attacks (myocardial infarctions). It helps prevent blood clot formation and reduces the risk of further cardiac damage.

Mechanism of Action (MOA): Acetylsalicylic acid is an antiplatelet agent. It works by inhibiting the activity of an enzyme called cyclooxygenase (COX). COX is involved in the production of prostaglandins, which play a role in platelet aggregation (clumping) and vasoconstriction.

Effect: By inhibiting COX, aspirin reduces the formation of thromboxane A2, a substance that promotes platelet aggregation and vasoconstriction. As a result, aspirin makes platelets less sticky and less likely to form blood clots. It primarily affects platelet function and is often used to prevent arterial thrombosis, such as in cases of myocardial infarction (heart attack) or stroke.

Dosage: The recommended dosage of acetylsalicylic acid for suspected heart attacks is typically 4 x 81 mg ‘baby aspirin’. EMTs should follow local protocols and medical direction regarding the specific dosage and formulation used.

Route: Aspirin is usually administered orally, which means EMTs may give the patient chewable or crushed aspirin tablets to be swallowed. It is important to ensure the patient can safely swallow the medication and has no contraindications.

Contraindications: EMTs should be aware of contraindications for aspirin administration, such as a known allergy to aspirin, active bleeding, or a history of gastrointestinal bleeding or ulcers. 

If the patient has any contraindications, aspirin should not be administered, and medical direction should be sought.

Documentation: EMS Providers should document the administration of aspirin, including the dosage, time, and the patient's response. Accurate documentation helps ensure continuity of care and provides important information to healthcare providers, including whether the patient has already taken aspirin.

Communication: EMTs should inform receiving healthcare providers about the administration of aspirin, including the dosage and timing. This helps ensure appropriate follow-up care and treatment continuation.

Remember, EMS Providers should always adhere to their local protocols and receive proper training on aspirin administration. They should work under medical direction and consult with a physician or follow local guidelines when administering aspirin to patients.