Lingering Dynamics in Microvascular Blood Flow

TL;DR

This study investigates the lingering effects of red blood cell dynamics at vessel bifurcations in vivo, revealing how these effects influence blood flow distribution and can cause partial blockages, with implications for microvascular health.

Contribution

It provides the first detailed in vivo analysis of lingering RBC effects at vessel bifurcations, linking numerical models with experimental observations.

Findings

Lingering effects cause uneven blood flow distribution.

Partial blockages can occur due to lingering RBCs.

In vivo evidence supports numerical predictions.

Abstract

The microvascular networks in the body of vertebrates consist of the smallest vessels such as arterioles, capillaries, and venules. The flow of RBCs through these networks ensures the gas exchange in as well as the transport of nutrients to the tissues. Any alterations in this blood flow may have severe implications on the health state. Since the vessels in these networks obey dimensions similar to the diameter of RBCs, dynamic effects on the cellular scale play a key role. The steady progression in the numerical modeling of RBCs, even in complex networks, has led to novel findings in the field of hemodynamics, especially concerning the impact and the dynamics of lingering events, when a cell meets a branch of the network. However, these results are yet to be matched by a detailed analysis of the lingering experiments in vivo. To quantify this lingering effect in in vivo experiments, this study analyzes branching vessels in the microvasculature of Syrian golden hamsters via intravital microscopy and the use of an implanted dorsal skinfold chamber. It also presents a detailed analysis of these lingering effects of cells at the apex of bifurcating vessels, affecting the temporal distribution of cell-free areas of blood flow in the branches, even causing a partial blockage in severe cases.