Mathematical Model of Platelet Turnover in Thrombocytopenic and Non

Abstract 26 Neonatal thrombocytopenia affects 22-35% of all neonates admitted to neonatal intensive care 27 units. The purpose of this study was to develop a mathematical model for characterizing platelet 28 (PLT) kinetics in thrombocytopenic pre-term neonates. Immature platelet fraction (IPF) and 29 platelet counts were measured for up to 35 days after birth in 27 very low birth weight pre-term 30 neonates. Platelet transfusions were administered to 8 of the 27 (24%) subjects. The final model 31 included a series of 4 transit compartments to mimic the production and survival of IPF and PLT. 32 Model parameters were estimated using nonlinear mixed effects modeling with the maximum 33 likelihood expectation maximization algorithm. The model adequately captured the diverse 34 phenotypes expressed by individual subject profiles well. Typical population survival values for 35 IPF and PLT lifespans in non-thrombocytopenic patients were estimated at 0.912 and 10.7 days, 36 respectively. These values were significantly shorter in thrombocytopenic subjects, 0.429 and