A -year-old woman is admitted to the hospital with a newly diagnosed acute pulmonary embolism. She is hemodynamically stable and has no significant past medical history. Her only home medication is an oral contraceptive pill. Her body mass index is kg/m , and her serum creatinine is mg/dL. The medical team initiates therapeutic-dose subcutaneous enoxaparin. They plan to transition her to an oral anticoagulant prior to discharge. During the initial period while she is receiving solely enoxaparin, which of the following is the most appropriate strategy for monitoring the anticoagulant effect of this medication?
- ASerial activated partial thromboplastin time measurements
- BDaily prothrombin time and international normalized ratio
- CPeak anti-factor Xa level measurement
- DSerial D-dimer measurements
- No routine laboratory monitoring of anticoagulant effect is indicatedAnswer
Answer
No routine laboratory monitoring of anticoagulant effect is indicated.
Low molecular weight heparins (LMWHs) such as enoxaparin have highly predictable bioavailability and dose-response relationships when administered subcutaneously. In patients with normal renal function and typical body weight, the anticoagulant effect is reliable, and therefore routine laboratory monitoring is not required. If monitoring becomes necessary due to altered pharmacokinetics (such as in patients with severe renal disease, significant obesity, or pregnancy), peak anti-factor Xa levels should be measured. This patient has normal renal function and a normal body mass index, meaning no specific therapeutic laboratory monitoring is indicated.
Step-by-Step Solution
Key Concept
Low molecular weight heparins (LMWHs) typically do not require routine laboratory monitoring of their anticoagulant effect due to their predictable pharmacokinetics, except in special populations (e.g., severe renal impairment, extreme obesity, pregnancy).
Estimated Time:45s