... I am currently on coumadin due to bilateral PE's and DVT's behind both knees related to a surgery in 2/12. My question relates to info from my orthopaedic surgeon that I go off coumadin 1 week before surgery and may be put on a different molecular weight Lovenox (from the one that got me ready for coumadin) right after stopping coumadin. I understand the Lovenox is taken until 9 hours pre-surgery and started several hours after surgery. My understanding is that the Lovenox lowers the INR-Proth. number but still keeps new clots from forming e.g. DVT's. I have an IVC filter to supposedly prevent more PE's. Has anyone gone thru this pre and post surgery anticoagulant procedure? Was it sucessful? How much later did they put you back on coumadin? Did you have to use the Lovenox used in the past before starting coumadin before for the next transition to coumadin after surgery?