Considerable information on the pharmacodynamics of betalactams has accumul
ated throughout the past 20 years demonstrating a time-dependent killing an
d some pharmacodynamic differences in the type of activity in-vitro and in
animal models that should have clinical significance. Unfortunately few cli
nical studies have directly examined the effects of different dosages that
might be predicted to result in failure or success of the outcome, particul
arly in serious sepsis.
Thus on the basis of a long preclinical and clinical experience we propose
a pharmacodynamic classification of betalactam antibiotics.
Three classes are delineated by the extent of PBP pattern saturation, bioma
ss increase, PAE length and initial killing power.