[Analysis of ceftazidime and ampicillin tissue distribution using physiologic models of pharmacokinetics]

Physiological models of ceftazidime and ampicillin pharmacokinetics were used to study accumulation of the antibiotics in the tissue interstitial space and to analyze the influence of the regional blood flow rate on the accumulation. For the control of the model adequacy, the published pharmacokinetic data on the distribution of ceftazidime and ampicillin in serum and "skin blister" fluid were used. The pharmacokinetic profiles calculated from the equations of the physiological models including Kp corresponded to the kinetics of the changes in the content of the cephalosporins and penicillins in the tissue homogenates. To estimate the antibiotic accumulation in the tissue interstitial space, it was necessary to use the equations where Kp = 1. Introduction of the coefficient regulating the regional blood flow rate to the equations made it possible to analyze the influence of the blood supply characteristics on the local pharmacokinetics.