Blood Flow Versus Hematocrit in Optimization of Oxygen Transfer to Tissue During Fluid Resuscitation.
The effectiveness of fluid resuscitation regimens in hemorrhagic trauma is assessed based on its ability to increase oxygen concentration in tissue. Fluid resuscitation using both crystalloids and colloids fluids, creates a dilemma due to its opposing effects on oxygen transfer. It increases blood flow thereby augmenting oxygen transport but it also dilutes the blood simultaneously and reduces oxygen concentration thereby reducing oxygen transport. In this work we have studied these two opposing effects of fluid therapy on oxygen delivery to tissue. A mathematical model of oxygen diffusion from capillaries to tissue and its distribution in tissue was developed and integrated into a previously developed hemodynamic model. The capillary-tissue model was based on the Krogh structure. Compared to other models, fewer simplifying assumptions were made leading to different boundary conditions and less constraints, especially regarding capillary oxygen content at its venous end. Results showed that oxygen content in blood is the dominant factor in oxygen transport to tissue and its effect is greater than the effect of flow. The integration of the capillary/tissue model with the hemodynamic model that links administered fluids with flow and blood dilution indicated that fluid resuscitation may reduce oxygen transport to tissue.
['Siam|Jamal|J|', 'Kadan|Marwa|M|', 'Flaishon|Ron|R|', 'Barnea|Ofer|O|']
D001783:Blood Flow Velocity D001784:Blood Gas Analysis D002196:Capillaries D003198:Computer Simulation D004058:Diffusion D005440:Fluid Therapy D006400:Hematocrit D006439:Hemodynamics D006470:Hemorrhage D006801:Humans D008955:Models, Cardiovascular D010100:Oxygen D010101:Oxygen Consumption D010313:Partial Pressure D012151:Resuscitation
Hemorrhage Oxygen delivery Capillary-tissue model Computer simulation Fluid replacement