Optimization of heparinization in clinical double filtration plasmapheresis.

Heparin has generally been used as an anticoagulant during plasmapheresis. In this study plasma heparin levels were studied in nine patients before double filtration plasmapheresis (DFPP), 30, 60 and 120 minutes after the start of DFPP and at the end of DFPP. Prothrombin time (PT), activated partial thromboplastin time (APTT), bleeding time (BT), plasma fibrinogen levels, FDP and general blood cell examination (CBC) were measured pre and post DFPP. Heparin levels in plasma were lower than 1 (IU/ml) under the dosage of heparin nearly 40 IU/kg/h of heparin administered during DFPP. APTT before DFPP (36.5 +/- 8.2 sec) was nearly double the post-DFPP value (61.4 +/- 12.2 sec). In two patients who were given 30 IU/kg/h of heparin during DFPP, clotting occurred in the DFPP circuit. In conclusion, the optimized dosage of heparin was 40 IU per kg of body weight per hour during DFPP.