β-Lactam pharmacokinetics and pharmacodynamics in critically ill patients and strategies for dose optimization: A structured review

Infections and related sepsis are two of the most prevalent issues in the care of critically ill patients, with mortality as high as 70%. Appropriate antibiotic selection, as well as adequate dosing, is important to improve the clinical outcome for these patients. beta-Lactams are the most common antibiotic class used in critically ill sepsis patients because of their broad spectrum of activity and high tolerability. beta-Lactams exhibit time-dependent antibacterial activity. Therefore, concentrations need to be maintained above the minimum inhibitory concentration (MIC) of pathogenic bacteria. beta-Lactams are hydrophilic antibiotics with small distribution volumes similar to extracellular water and are predominantly excreted through the renal system. Critically ill patients experience a myriad of physiological changes that result in changes in the pharmacokinetics (PK) of hydrophilic drugs such as beta-lactams. A different approach to dosing with beta-lactams may increase the likelihood of positive outcomes considering the pharmacodynamics (PD) of beta-lactams, as well as the changes in PK in critically ill patients. The present review describes the strategies for dose optimization of beta-lactams in critically ill patients in line with the PK and PD of these drugs.