[Kinetics of anticoagulation in hemodialysis. Sequential study of single, intermittent and continuous heparinization].

A sequential real-time study was run to monitor plasma heparin values following three standard dose protocols during 4-hr dialysis, using an enzymatic method. One group of patients was given a single dose of 7000 IU at the commencement of dialysis, a second group 5000 IU at the start and 2500 IU at the end of the third hour, and a third group 2500 IU at the start and 1500 UI/hr for four hours. Plasma levels were checked every hour and ranged from 0.702 IU/ml (+/- 0.069) (start) to 0.290 IU/ml (+/- 0.079) (end) in the first group, 0.552 (+/- 0.116) to 0.312 (+/- 0.09) in the second, and 0.456 (+/- 0.113) to 0.314 (+/- 0.063) in the third. Correlation of heparin levels with coagulation time led to the establishment of an optimal range of 0.2 to 0.6 IU/ml.