Dosing of antimicrobial agents in critically-ill patients with acute kindey injury and continuous venvenous haemofiltration

Objective To summarize the general guidelines for drug dosing in critically-ill patients with acute kidney injury and continuous venovenous haemofiltration (CVVH), and to discuss whether the predicted dose adjustment is an as reliable estimate than one based on observed data, considering the recent literature. Methods Literature search was done in PubMed database for human studies. Conclusions In critically-ill patients receiving CVVH, dosing of antibiotics based on the predicted clearances yield rough estimates. Because of interpatient variability observed in the clearance of many antibiotics, monitoring of plasma concentration is highly recommended whenever possible, and especially for those antibiotics that are eliminated predominantly by the kidney, and that have a low therapeutic threshold such as aminoglycosides and glycopeptides, or in patients requiring protracted treatment. However, for many antibiotics, monitoring of blood concentrations is not routinely available and adequate concentrations can only be inferred from clinical response. Therefore, it is important to realize that among many other causes, failure to respond within the first few days of antibiotic treatment may be due to inadequate dosing.