Effect of oxygen-carrying resuscitation fluids on the pharmacokinetics of antipyrine, diazepam, penicillin, and sulfamethazine in rats

The effects of exchange transfusion with an oxygen-carrying resuscitation fluid, Fluosol DA 20% or stroma-free hemoglobin, on the pharmacokinetics of antipyrine, diazepam, penicillin, and sulfamethazine were studied in rats. After transfusion with Fluosol DA 20% or stroma-free hemoglobin the pharmacokinetics of antipyrine, diazepam, and penicillin were unchanged when compared to control animals. After transfusion with Fluosol DA 20%, the t 1/2 of sulfamethazine was increased from 3.15 ± 0.56 to 7.65 ± 2.41 hr (p < 0.05) and the Vd was increased from 60.7 ± 17.5 to 152 ± 16 ml (p < 0.05). In contrast, after transfusion with stroma-free hemoglobin, the AUC of sulfamethazine was decreased from 129 ± 28 to 80.5 ± 27.7 μg.h.ml^-1 (p < 0.05) and there was an increase in Cl from 12.2 ± 3.4 to 20.2 ± 6.0 ml.h^-1 (p < 0.05) and Vd from 60.1 ± 11.8 to 132 ± 49 ml (p < 0.05). The reason for these alterations is not clear. Fluosol DA 20% and stroma-free hemoglobin may alter the acetylation of sulfamethazine.