Dosing of antibiotics in critically ill patients: are we left to wander in the dark?

Critically ill patients are frequently affected by acute kidney injury accompanied by dysfunction of other systems and organs. Sepsis is common in this population and remains a major cause of multiorgan dysfunction syndrome, indicating a crucial role in efficient antibiotic treatment. However, such treatment is particularly difficult due to altered pharmacokinetic profile in these patients, dynamic changes in their clinical status and, in many cases, need for renal replacement therapy (RRT). Current guidelines concerning the dosing of antibiotics in this patient population are not particularly reliable because they are based on studies involving small and heterogeneous groups of patients, often treated with different RRT modalities. Our paper reviews the basic pharmacokinetic and pharmacodynamic parameters as well as other factors that should be considered while devising a proper therapeutic approach for this patient population.