OBJECTIVES: The epileptogenic activity of imipenem in rats with experimentally induced hypovolaemia or endotoxaemia was investigated by pharmacokinetic-pharmacodynamic modelling of the electroencephalogram effect. METHODS: Hypovolaemia was induced by removal of 30% of the blood volume and endotoxaemia by intravenous lipopolysaccharide injection. RESULTS: Imipenem clearance and volume of distribution values of 16.4+/-1.1 mL/min per kg and 357+/-49 mL/kg (mean+/-S.E.M.) in healthy rats (n=5), were significantly reduced in hypovolaemic (n=6) and endotoxaemic (n=6) animals. A dose reduction from 250 mg/kg to 120 mg/kg was necessary in endotoxaemic rats. The pharmacokinetic-pharmacodynamic model with an effect compartment previously developed in healthy rats described the data adequately and pharmacodynamic parameters in hypovolaemic and endotoxaemic rats were not significantly different from corresponding values estimated in the control group. CONCLUSION: Hypovolaemia and endotoxaemia only had an effect on imipenem pharmacokinetics.
OBJECTIVES: The epileptogenic activity of imipenem in rats with experimentally induced hypovolaemia or endotoxaemia was investigated by pharmacokinetic-pharmacodynamic modelling of the electroencephalogram effect. METHODS: Hypovolaemia was induced by removal of 30% of the blood volume and endotoxaemia by intravenous lipopolysaccharide injection. RESULTS:Imipenem clearance and volume of distribution values of 16.4+/-1.1 mL/min per kg and 357+/-49 mL/kg (mean+/-S.E.M.) in healthy rats (n=5), were significantly reduced in hypovolaemic (n=6) and endotoxaemic (n=6) animals. A dose reduction from 250 mg/kg to 120 mg/kg was necessary in endotoxaemic rats. The pharmacokinetic-pharmacodynamic model with an effect compartment previously developed in healthy rats described the data adequately and pharmacodynamic parameters in hypovolaemic and endotoxaemic rats were not significantly different from corresponding values estimated in the control group. CONCLUSION: Hypovolaemia and endotoxaemia only had an effect on imipenem pharmacokinetics.