A Computational Study of the Effect of Capillary Network Anastomoses and Tortuosity on Oxygen Transport

✍ Scribed by DANIEL GOLDMAN; ALEKSANDER S POPEL

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 410 KB
• Volume: 206
• Category: Article
• ISSN: 0022-5193
• DOI: 10.1006/jtbi.2000.2113

✦ Synopsis

The objective of this study was to investigate the e!ects of capillary network anastomoses and tortuosity on oxygen transport in skeletal muscle, as well as the importance of muscle "bers in determining the arrangement of parallel capillaries. Countercurrent #ow and random capillary blockage (e.g. by white blood cells) were also studied. A general computational model was constructed to simulate oxygen transport from a network of blood vessels within a rectangular volume of tissue. A geometric model of the capillary network structure, based on hexagonally packed muscle "bers, was constructed to produce networks of straight unbranched capillaries, capillaries with anastomoses, and capillaries with tortuosity, in order to examine the e!ects of these geometric properties. Quantities examined included the tissue oxygen tension and the capillary oxyhemoglobin saturation. The computational model included a two-phase simulation of blood #ow. Appropriate parameters were chosen for working hamster cheek-pouch retractor muscle. Our calculations showed that the muscle-"ber geometry was important in reducing oxygen transport heterogeneity, as was countercurrent #ow. Tortuosity was found to increase tissue oxygenation, especially when combined with anastomoses. In the absence of tortuosity, anastomoses had little e!ect on oxygen transport under normal conditions, but signi"cantly improved transport when vessel blockages were present.