Pilot trial of selective decontamination for prevention of bacterial infection in an intensive care unit

Preventing nosocomial pneumonia: state of the art and perspectives for the 1990s

In the 1980s, nosocomial pneumonia became the second most common nosocomial infection in the United States. Gram-negative bacilli and Staphylococcus aureus were the most frequently isolated bacteria. Methods to improve the diagnostic sensitivity and specificity included transtracheal aspirates and bronchoscopy with protected specimen brush or bronchoalveolar lavage. Multivariate analysis was used to identify independent risk factors for pneumonia and fatality in different subsets of high-risk patients. Gastric pH and colonization were evaluated as risk factors for pneumonia in mechanically ventilated patients. Colonized respiratory therapy equipment and contaminated tubing condensate and in-line medication nebulizers were suggested as possible sources of nosocomial pathogens. Staff education programs, the use of barrier precautions, and selective decontamination of the digestive tract were associated with reduced rates of lower respiratory tract infection. Despite a decade of progress in our understanding of nosocomial pneumonia, progress in the 1990s will undoubtedly include molecular epidemiologic techniques, appropriate application of risk factor data, and the use of new methods for the diagnosis of pneumonia. Prevention strategies should focus on more effective infection control techniques, improved invasive devices/equipment, and the judicious use of antibiotics for treatment and prophylaxis.

Epidemiology and control of nosocomial infections in adult intensive care units

Traditional infection control measures in intensive care units (ICUs) have been directed at limiting person to person spread of infection and improving care of invasive devices. These measures often fail because they have little effect on patients' endogenous flora, which is an important source of infection in ICUs. Improvements in the design and aseptic care of invasive devices have helped to decrease the risk of progression from colonization to infection in individual patients. Interest is growing also in use of selective decontamination to decrease ICU infection rates. Despite these advances, basic hygiene and appropriate, prospectively monitored use of antibiotics remain essential components of ICU care.

Failure of infection control in intensive care units: can sucralfate improve the situation?

Conventional infection control measures in intensive care units (ICUs) are aimed primarily at stemming cross-infections. The role of patients' endogenous flora in the pathogenesis of nosocomial infection and occasional lapses in aseptic technique in ICUs help to explain the frequent failure of the conventional approaches. Newer control strategies include avoiding gastric and oropharyngeal overgrowth of gram-negative bacilli by using sucralfate to avoid gastric alkalinization and/or suppressing nosocomial flora by use of topical antimicrobials.

Selective decontamination of the digestive tract (SDD) in intensive care patients: a critical evaluation of the clinical, bacteriological and epidemiological benefits

Twenty trials (17 controlled and three observational cohort studies) on selective decontamination of the digestive tract (SDD) have been undertaken to date. SDD is defined as a technique which aims to eradicate carriage of disease-causing microorganisms by means of lethal oropharyngeal and faecal antimicrobial concentrations. The SDD concept and the criteria for the choice of the antimicrobials used in the SDD programme are explained. Abolition of the carrier state is thought to provide clinical, bacteriological and epidemiological benefits. Infection-specific morbidity and mortality, emergence of antibiotic resistance and outbreaks are the main endpoints evaluated in this review. Of the 15 controlled studies that considered carriage, 14 demonstrated a significant reduction of Gram-negative bacillary (GNB) carriage. Severe infections, including pneumonia and septicaemia, caused by enterobacteria and pseudomonads have been virtually eliminated in these trials. Five of the 12 centres that evaluated mortality showed a significant decrease among patients who received SDD. Two recent trials describe the control of an outbreak with a multiresistant Klebsiella by SDD. There are three indications for the use of SDD so far: (i) in trauma patients; (ii) in certain elective surgical procedures including liver transplantation and oesophageal resection; and (iii) in control of outbreaks of ICU infection. Future lines of research may include a properly designed trial with mortality as endpoint and studies on the transfer of SDD from the ICU into the ward as part of prophylaxis in major surgery.