Antimicrobial Therapy for ICU-Acquired Infection: Time for a Reappraisal

Infections acquired in the intensive care unit (ICU) commonly complicate the course of critical illness. Approximately one fourth to one third of patients admitted to an ICU develop one or more episodes of nosocomial infection [1]; both mortality and morbidity are sharply elevated in this population [2] (Table 1). Yet the extent to which such infections are the cause of excess morbidity and mortality, rather than an additional manifestation of organ dysfunction in a subset of the sickest of critically ill patients, is unclear. Equally, although antibiotics are among the most prescribed pharmaceutical agents in contemporary ICUs, it is not at all established that their widespread use in the management of suspected or proven ICU-acquired infection results in net clinical benefit. Indeed there are reasons to suspect that the opposite may be true. A recent analysis of nosocomial infection following cardiac surgery found that the administration of empiric post-operative antibiotics was an independent risk factor for the development of subsequent nosocomial infection [3].