High microparticle concentration in cord plasma.

We investigated if differences in the microparticle concentration and activity between newborn cord plasma and adult plasma exist. Methods: To enumerate and characterize microparticles (MP) FACS and ELISA were used. The effect of microparticles derived tissue factor (TF) on thrombin generation was measured indirectly by CAT (calibrated automated thrombography). Results: The flow cytometric measurements revealed an increased microparticle concentration in newborn cord compared with adult plasma. By the use of ELISA a significantly increased procoagulant activity of microparticles was found in newborn cord plasma as compared to adult plasma. Initiation of thrombin generation by adding phospholipids alone resulted in a significant lower prolongation of the lag time, time to peak in cord plasma, while the decrease of endogenous thrombin potential (ETP) and peak was comparable between newborns and adults. Conclusion: Our results show a higher impact of microparticles on the haemostatic system of newborns than on that of adults. The three methods suggest a somewhat increased microparticle activity in newborn cord plasma, but argue against strong platelet activation during birth.