Comparison of standard and global hemostasis assays in cord and peripheral blood of newborns.

ABSTRACT

BACKGROUND: Umbilical cord blood is used for the testing of various parameters in newborns. However, data on its applicability for hemostasis assays is insufficient. OBJECTIVE: To evaluate whether umbilical cord blood can be used for standard tests, thromboelastometry and thrombodynamics for preterm and term newborns. METHODS: 187 newborns were included in the study. Blood was taken from the umbilical cord and by venipuncture of the newborn. Clotting times, fibrinogen, D-dimer, thromboelastometry and thrombodynamics were measured. RESULTS: Clotting times and fibrinogen indicated a hypocoagulable shift, while thromboelastometry and thrombodynamics showed a hypercoagulable shift in hemostasis in umbilical cord blood compared to newborn blood. D-dimer indicated an enhanced process of thrombus lysis in newborn blood compared to cord blood. Collecting blood into a tube with the addition of a contact pathway inhibitor did not significantly change the global assay parameters in either umbilical cord blood or newborn blood. In the thrombodynamics assay, spontaneous clotting was detected but suppressed by the addition of a tissue factor inhibitor. CONCLUSIONS: Hemostasis in cord and newborn blood differs for both global and standard tests. Hypercoagulability in newborns registered with the global assay thrombodynamics is associated with the presence of tissue factor in the blood. IMPACT STATEMENT 1. We found a hypercoagulation shift in newborns compared with the adult references, possibly due to the presence of tissue factor in blood. 2. Blood coagulation is enhanced in cord blood compared with blood sampled from the vein of a newborn according to thromboelastometry and thrombodynamics assays. 3. Clotting times and fibrinogen concentrations in cord blood differ from these parameters in newborn blood. 4. Studying of the (patho)physiological features of hemostasis in newborns should consider differences in cord blood and vein sampled blood.