From the Guidelines
For patients with non-ST-elevation myocardial infarction (NSTEMI), the recommended dose of enoxaparin is 1 mg/kg administered subcutaneously every 12 hours, as supported by the highest quality evidence from the 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes 1. This dose should be continued for the duration of hospitalization, typically 2-8 days, or until percutaneous coronary intervention (PCI) is performed.
- For patients with severe renal impairment (creatinine clearance <30 mL/min), the dose should be reduced to 1 mg/kg once daily, as recommended by the guidelines 1.
- An initial intravenous bolus of 30 mg may be given before starting the subcutaneous regimen, particularly in high-risk patients, as mentioned in the guidelines 1.
- Weight-based dosing is important for efficacy and safety, so accurate patient weight should be obtained.
- Blood tests to monitor anti-Xa levels are not routinely required but may be considered in patients with obesity (>150 kg), pregnancy, or renal dysfunction.
- Enoxaparin works by enhancing antithrombin activity and inhibiting factor Xa, thereby preventing further clot formation in the coronary arteries.
- Bleeding risk should be assessed before initiating therapy, and concomitant use with other anticoagulants or antiplatelet agents requires careful monitoring, as emphasized in the guidelines 1.
From the Research
Dose of Enoxaparin for NSTEMI
- The dose of enoxaparin for Non-ST-Elevation Myocardial Infarction (NSTEMI) is not explicitly stated in the provided studies 2, 3, as these studies focus on ST-segment elevation myocardial infarction (STEMI).
- However, a study published in 2007 4 reports the use of reduced-dose enoxaparin in patients with NSTEMI, with a mean dose of 0.51 mg/kg.
- Another study published in 2012 5 used a subcutaneous enoxaparin dose of 1 mg/kg twice daily, initiated after the patient's arrival and continued until 3-5 days after percutaneous coronary intervention (PCI).
- It is essential to note that the dosing regimens may vary depending on the specific clinical context and patient population, and the provided studies may not directly address the question of enoxaparin dosing for NSTEMI.
Considerations for Enoxaparin Dosing
- Patient age and renal function should be considered when determining the enoxaparin dose, as reported in studies 2, 3.
- The dose of enoxaparin may need to be adjusted in patients with estimated creatinine clearance <30 mL/min, with a recommended dose reduction to 1 mg/kg every 24 hours 2, 3.
- Patients ≥75 years of age may require a reduced dose of enoxaparin, with no initial bolus and a 12-hourly dose reduction to 0.75 mg/kg 2, 3.