Pneumonia in the surgical patient: duration of therapy and does the organism matter?

Pneumonia is a frequent complication in the critically ill surgical or trauma patient. Despite its common occurrence and increased attention recently, many basic issues, such as how long to treat and whether the exact causative organism even matters, remain unanswered. Currently, cessation of treatment is based on clinical response, although some data suggest that both the microbiologic and immunologic response within the lung are also important. A thorough knowledge of the likely causative organisms for both early and late pneumonia should allow safe and efficacious empiric antibiotic selection.