[Heparin and antiheparin in childhood. 3. Heparin level measurements and their importance in heparin monitoring].

Measurements of the heparin level were made under continuous anticoagulation in a total of 7 patients. For the purpose of monitoring heparin the coagulation time values were determined parallelly. Except a patient with a sepsis and a 7 days old newborn baby the desired prolongation for the partial thromboplastin time and the reaction time of thrombelastogram resulted from heparin titres lying within the range of 0.2-0.7 U/ml of plasma. Even after applying depot preparations there was a relatively good correspondance of heparin level curves and coagulation parameters. In childhood the partial thromboplastin time is primarily suitable for monitoring the heparin therapy. Heparin half-life times calculated during the transumbilical exchange transfusion in 7 children amounted to values ranging between 40-110 minutes. In addition to checking low dose heparinizing, measurements of the level are suitable for deriving dosage standards for neutralizing heparin effects by protamine sulfate.