Tissue Distribution of Beta-Lactam Antibiotics: Continuous versus Bolus Dosing

Background: In vitro studies suggest that administering betalactam antibiotics by continuous infusion may maximise efficacy. Several pharmacokinetic studies have compared the distribution of beta-lactam antibiotics administered by continuous and bolus dosing in plasma and tissues. Knowledge of pharmacokinetic exposure to tissues is essential, as tissue sites are most commonly the ‘target site’ for antibiotic therapy. Aim: To identify published studies that measure the serum and tissue concentrations of beta-lactam antibiotics administered by continuous and bolus dosing. Data sources: A number of studies in animals, healthy volunteers and hospitalised patients were identified. Results: More prospective clinical trials are required to validate that the continuous infusion of beta-lactam antibiotics attain better tissue distribution at the target site. Conclusion: Beta-lactam antibiotics administered by continuous infusion maintain higher concentrations in serum and tissue. There is also compelling evidence that tissue distribution of antibiotics is impaired with increased sickness severity, therefore, larger doses of beta-lactam antibiotics may be required in severely sick patients to optimise antibiotic exposure at the target site