title: Penetration of antibiotics into vegetation of heart valves: a mathematical model.
abstract: The effect of vegetation size upon the concentration of antibiotic within various points of a fibrin-clot heart valve vegetation such as ones found in bacterial endocarditis was examined. A mathematical model based upon Fick's second law of diffusion was developed and solved on a PDP-II computer. The antibiotic was assumed to have a half-life of 30 min and intermittently injected intravenously every 4 h. After 5 simulated antibiotic doses, peak and trough levels of the antibiotic near the center of the vegetations of sizes 0.5, 1.0, 2.0 cm were, respectively, 37 and 3%, 22 and 15%, and 18 and 18% of the free serum antibiotic concentration. This model can be used to estimate antibiotic levels in different areas of a valvular vegetation.
mesh_terms: D000042:Absorption; D000900:Anti-Bacterial Agents / Q000378:metabolism*; D003201:Computers; D004697:Endocarditis, Bacterial / Q000378:metabolism; D006207:Half-Life; D006349:Heart Valve Diseases / Q000378:metabolism*; D006801:Humans; D008962:Models, Theoretical
chemical_list: D000900:Anti-Bacterial Agents