To date the use of heparin in the CFC has not been adequately controlled, thus exposing donors and patients to coagulation disorders. For this reason, we decided to evaluate the use of heparin by continuous infusion in dosages that would be modified by a simultaneous assessment of its anticoagulant effect, as shown by the thrombin time dilution test (TTDT).The study was performed during 46 leukopher- esis and 27 plasmapheresis. It was ascertained that heparin is an efficient anticoagulant in the CFC, using the TTDT as an effective and reliable method for its control. The initial dose in leukopheresis is one unit per milliliter of blood during the first hour, then half the dose during the next hour, and then a quarter of the dose until the procedure is completed. A TTDT performed every hour will indicate whether the amount of heparin used should be modified. For plasmapheresis, it is neccesary to establish a specific dose in each instance, using the TTDT as described. In most of the subjects, the anticoagulant level was exactly right. There was no case of bleeding or extracorporeal coagulation of the blood.On the basis of these findings, we recommend the use of heparin in the CFC, applying the results of the TTDT as a guide for its dosage level.
Principles of blood separation and component extraction in a disposable continuous-flow single-stage channel
