Management of antimicrobial use in the intensive care unit.

Indications for the use of antimicrobials in critically ill patients are similar to those for other hospitalised patients. However, the selection of agents depends on the particular characteristics of patients in the intensive care unit (ICU), the form of presentation of infection, the type of infection and the bacteriological features of the causative pathogens. The use of antimicrobials in patients admitted to medical-surgical ICUs varies between 33 and 53%. The selection of empirical antimicrobials to be included in treatment protocols of the most common infections depends on the strong interrelationship between patient characteristics, predominant pathogens in each focus. and antimicrobials used for treatment. Epidemiological studies carried out in the past have identified the microorganisms most frequently responsible for community-acquired and nosocomial infections in patients admitted to ICUs. Susceptibility to antimicrobial agents may be different between each geographical area, between each hospital and even within the same hospital service. In addition, susceptibility patterns may change temporarily in relation to the use of particular antimicrobials or in association with other unknown factors so that assessment of endemic antimicrobial resistance patterns is very useful in order to tailor the antimicrobial regimens of therapeutic protocols. Antimicrobial use should not be a routine procedure. The clinical course of the patient (an indicator of effectiveness) should be closely monitored as well as the possible appearance of adverse effects and/or multiresistant pathogens. Controls are based on the assessment of plasma drug concentrations and microbiological surveillance to detect the presence of multiresistant strains or new antibacterial-resistant pathogens. Prevention of the development of multiresistant pathogens is the main goal of the ICU antimicrobial policy. Although a series of general strategies to reduce the presence of multiresistant pathogens have been proposed, the implementation of these recommendations in ICUs requires the cooperation of a member of the intensive care team.