Absolutely as it is based on the ACT. The ACT required also depends on whether the patient is on or off the bypass pump for the operation. This just smells a little like bovine thrombin antbodies to factor 5. I just now called another cardiac anesthesiologist who used to work at univ of miami/Jackson back when they were doing 1500 hearts/year. He then and now just gives more heparin to overcome the resistance. He said once or twice a year they would give FFP (which was no big deal).