Selective Gut Decontamination in Ventilated Patients

Infection has remained a significant cause of morbidity and mortality in critically ill patients despite the discovery of potent antimicrobials and sophisticated supportive treatment measures. Infections in general ICU occur at rates of 15–20 per 100 patient admissions, thereby exceeding the average rates in general wards by approximately 3–4 fold [1,2]. Intubated patients are a subset of patients who exhibit an extraordinary high risk of developing respiratory infections [3]. Rates of pneumonia in intubated patients receiving mechanical ventilation are increased about 10 fold compared to patients with no respiratory device so that the majority of the pneumonias in the ICU occur in patients who are receiving or have had ventilatory support [3, 4]. Patients with nosocomial infections show prolonged hospitalization and increased risk of death as compared to their matched controls [5, 6]. Bacteremias and pneumonias are not only the predominant infections in ICU patients, but are also associated with the highest mortality rate [7]. Crude mortality rates for pneumonias have been reported to be in the range of 30 to 50% [3, 7]. However the mortality attributable to infection is difficult to assess and varies considerably between various groups. Patients with advanced underlying diseases or multiorgan failure run a very high risk of developing life-threatening infection and are also very likely to die in consequence of infection. Nevertheless, infection may contribute little to the overall mortality in these patients since their risk of dying is very high anyway. On the other hand, patients who do not suffer from serious underlying disease can be expected to have a relatively low infection risk and also a low mortality rate, but severe infection in these patients may largely influence the outcome [7].