The last few months have been a never ending string of medical issue with Quinn. His VWD kicked in big time. He was diagnosed with Addisons, had a major case of ringworm and a nasty skin infection. He has been having with his ears. Several areas on the pinnae died off. This caused major bleeding issues for awhile. The thing I hadn't noticed was that the tip of Quinns (natural) tail had also lost blood supply. I was horrified to come home and find that he had chewed a big chunk of it off. I know it needs to be repaired, I just worry about surgery. The docotr said we will treat with DDAVP before hand. This is where my question comes in. He said we will treat the day prior to surgery. I have read a few places that it only has effect for a few hours. How long does the VWD factor that is produced stay in the body? I had always assumed that the treatment was given the day of surgery.