The Effects of Aspirin:
Aspirin (ASA) blocks the formation of thromboxane A2, thereby inhibiting the sticking together of platelets and reducing clot formation. Using aspirin for myocardial infarctions helps to reduce death and the probability of reinfarction and stroke.
Aspirin Indications for Use:
Aspirin is indicated in the presence of signs and symptoms of acute coronary syndromes.
Signs and symptoms could be:
- Chest pain
- Pain radiating into neck and jaw or down right or left arm
Another reason for using aspirin is when ECG changes are consistent with acute coronary syndrome. Examples of this include but are not limited to:
- ST elevation
- DT wave inversion
Aspirin Precautions & Contraindications:
Before giving aspirin, it is important to ask if a patient has:
- Known hypersensitivity (like Samter’s Triad)
- Bleeding disorders (like hemophilia)
- Active ulcer disease
- Recent gastrointestinal bleeding
Patients should also be asked if they have a severe allergy (like anaphylaxis) or asthma related to aspirin. This is different from a moderate sensitivity such as sneezing or stuffiness. If the patient does not have a severe allergy to aspirin, the benefits of using it would outweigh the negatives.
Adult Dosage for Aspirin:
The proper dose to administer is 2 to 4 chewable aspirin or 162-324 mg nonenteric coated aspirin as soon as possible after the onset of symptoms.
An aspirin suppository (usually a 300 mg dose) can be used as an alternative if the patient has:
- Severe nausea
- Gastrointestinal disorders
To achieve a rapid therapeutic blood level, the patient should be instructed to chew the aspirin before swallowing.