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arXiv · 1405.4835

Optimal villi density for maximal oxygen uptake in the human placenta

A. S. Serov·C. Salafia·P. Brownbill·D. S. Grebenkov·M. Filoche
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Abstract

We present a stream-tube model of oxygen exchange inside a human placenta functional unit (a placentone). The effect of villi density on oxygen transfer efficiency is assessed by numerically solving the diffusion-convection equation in a 2D+1D geometry for a wide range of villi densities. For each set of physiological parameters, we observe the existence of an optimal villi density providing a maximal oxygen uptake as a trade-off between the incoming oxygen flow and the absorbing villus surface. The predicted optimal villi density $0.47\pm0.06$ is compatible to previous experimental measurements. Several other ways to experimentally validate the model are also proposed. The proposed stream-tube model can serve as a basis for analyzing the efficiency of human placentas, detecting possible pathologies and diagnosing placental health risks for newborns by using routine histology sections collected after birth.

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A. S. Serov, C. Salafia, P. Brownbill, D. S. Grebenkov, M. Filoche. 2014-04-23. Optimal villi density for maximal oxygen uptake in the human placenta. https://doi.org/10.1016/j.jtbi.2014.09.022

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