An engineering model to characterize oxygen transfer rates for liposome encapsulated hemoglobin (LEH)

An engineering model was designed to evaluate oxygen transfer rates for LEH and other oxygen carriers under wall shear rates from 150 sec-1 to 450 sec-1. The results showed that increasing the shear rates (or flow rates) of oxygen carriers flowed inside of hollow fiber tubes would increase oxygen transfer rates to outside media. The values of overall oxygen transfer rate coefficients for LEH, based on 1 g/dl of hemoglobin contents, were about 2 to 2.5 times higher than those values for human blood at all of tested shear rates (e.g., 5.1 x 10(-5) cm/sec and 2.1 x 10(-5) cm/sec for LEH and blood at wall shear rates of 450 sec-1, respectively). Moreover, the results of oxygen transfer efficiency for LEH calculated by this model were consistent with the similar results reported by Usuba et al.[3] obtained by animal study. With an engineering model, we possibly estimate the effects of other factors such as viscosity on the oxygen transfer rates for LEH in microcirculation.