To examine the clinical efficacy of antibacterial
chemotherapy for life-threatening
pneumonia, we investigated the clinical outcome after a prolonged infusion regimen of
meropenem based on a pharmacokinetics/pharmacodynamics (PK/PD) theory. In 42 patients with severe
pneumonia, the clinical efficacy of a prolonged (4 h)
drip infusion regimen of
meropenem (4 h-group; 0.5 g, b.i.d.; 18 patients) was compared with that of a standard (0.5-1 hour) infusion regimen of
meropenem (1 h-group; 0.5 g, b.i.d.; 24 patients). Although there was no significant difference in the duration of
meropenem-administration and the rate of decrease in CRP between the 4 h-group and 1 h-group, the mortality rate in the 4 h-group (5.6%) was significantly lower (p < 0.05) than that in the 1 h-group (37.5%). In this study, the
meropenem-concentration in the blood of each patient and the MIC of
meropenem against the causative bacteria in each patient were not determined; however, it was thought that the superior life-saving effect of
meropenem in the 4h-group was mainly due to prolongation of the time above MIC realized by the prolonged infusion regimen. These results suggested that prolongation of infusion time of
meropenem was usefu for improvement of the clinical efficacy against life-threatening
pneumonia.