Spatio-temporal instabilities of blood flow in a model capillary network

The blood microcirculatory network is where nutrients, respiratory gases, and metabolic waste products are exchanged with the neighboring cells. Here, these components can take unexpected routes to get from one point to another. Whereas a simple fluid would follow the most direct route, we show in our $i\phantom{\rule{0}{0ex}}n$ $v\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}o$ experiments that red blood cells, which are responsible for oxygenating the body, can intermittently take side routes and remain in the network longer than expected. These observations, backed up by associated modeling, raise new questions regarding hypoxia mechanisms in organs, even under apparently healthy conditions.