Therapeutic efficacy of antimcrobials in critically ill patients

Abstract

At any time, 50% of patients in intensive care units are receiving antibiotics. Source control and early and appropriate antibiotics administration along with other measures are vital interventions for patients with sepsis. Dose optimization is one critical tool that should be use by clinicians to improve outcomes in critically ill patients. Adequate dosing of these patients not only can improve clinical outcomes but also can impact positively in the emergence of bacterial resistance in the unit. Patients with sepsis and systemic inflammatory response (SIR) suffer from hemodynamic changes such as increased cardiac output, reduced peripheral vascular resistance, changes in the volume of distribution, and fluid shifts. In this setting, other systemic changes frequently take place such as hypoalbuminemia, hepatic impairment, and acute modification of renal function (e.g., augmented renal clearance and acute kidney injury). All these physiological adjustments to SIR lead to changing drug concentrations in serum and at the infection site of the antibiotics prescribed for the underlying infection. In this regard, doses of antibiotics usually administered to non-critically ill patients are probably inadequate in most of those patients with sepsis or SIR. Knowing the pharmacokinetics and pharmacodynamics characteristics of each antibiotic is essential to optimize drug treatment in this setting. Individualizing dosing based on patient clinical status and antibiotic properties should be encouraged. Loading dose, continuous infusion of time-dependent antibiotics, therapeutic drug monitoring, and direct administration at the infection site are among the tools that could improve antimicrobial use in critically ill patients. Discussion of optimization options for most commonly used antibiotics in ICU will be presented.