Contemporary issues with bacterial infection in the intensive care unit.

Nosocomial infection in the critically ill results from defects in the intrinsic barriers to microbial invasion. The diagnosis is complicated by an inability to perform an adequate physical examination in a patient with several compounding findings, usually necessitating sophisticated technologies to aid in the diagnosis. Pneumonia, line sepsis, urosepsis, sinusitis, endocarditis, peritonitis, and acalculous cholecystitis are the more common infections that challenge the care of the critically ill. Antibiotic therapy is adjunctive to efforts to preserve the barrier, but should be started early, should be targeted as specifically as possible to the offending organisms, and should be dosed adequately to ensure an effective concentration in the infected tissue.