Reviewing Sue Bergs‘ March 23, 2012 post asking, How Many Use the Anti-Xa?, I noticed the comment appended by “Istano” asking for data on switching from PTT to anti-Xa heparin assay for routine heparin monitoring. My answer was somewhat incomplete, so I thought I should connect this question with Marisa Marques, MD‘s June 20, 2012 question, Do You Use Anti-Xa for Heparin?, Scott Miller‘s December 12, 2012 discussion of Anti-Xa Calibrators, and finally to my October 25, 2012 post,Clumsy Coag Communication, which provides PDFs of my October 16 presentation in Portland, Maine with references that support the use of the anti-Xa heparin assay. The handout also supports the chromogenic factor X assay as a substitute for the prothrombin time. I hope these subsequent posts help Istano and others who are making this switch.
Appended during review: Linking to an additional post on the same subject, “Heparin Brill-Edwards Curve Calibrators,” from Stephen Duff, December 21, 2011.