Laboratory monitoring of which of the following is desirable with low molecular weight heparin therapy in a patient with renal failure?: (A) aPTT, (B) CT, (C) PT, (D) Anti-factor Xa activity
Answer is D. LMW heparin and fondaparinux have long half lives and consistent SC absorption; therefore do not require monitoring and once daily SC doses are sufficient. Patients with end stage renal failure and morbid obesity may require monitoring with anti-factor Xa assay.