Decontamination in the ICU
Abstract & Commentary
By Stan Deresinski, MD, FACP, Clinical Professor of Medicine, Stanford, Associate Chief of Infectious Diseases, Santa Clara Valley Medical Center, is Editor for Infectious Disease Alert.
Synopsis: Oropharyngeal decontamination with topic antimicrobials was associated with a modestly improved survival.
Source: de Smet AM, et al. Decontamination of the digestive tract and oropharynx in ICU patients. N Engl J Med. 2009;360:20-31.
In a study designed to evaluate potential methods for improving survival by prevention of infection in ICU patients, de Smet et al used cluster randomization involving 13 centers in the Netherlands, with assignment to one of three treatment arms: selective decontamination of the gastrointestinal tract (SDD), selective oropharyngeal decontamination (SOD), or standard of care (SOC) (see Table). The cluster randomization also included a cross-over design. All three regimens were administered in each unit over the six months of the study, with the order of the regimens randomly assigned. Almost 6,000 patients participated in the study.
The crude mortality at day 28 was 26.6% in patients receiving SOC, 26.9% in those receiving SDD, and 27.5% in those receiving SOC. The odds ratios for death for the SOD and SDD groups, compared to SOC, were 0.86 and 0.83, respectively, with each achieving statistical significance. The absolute and relative reductions in mortality for the SDD group were 3.5% and 13%, respectively, and for the SOD group were 2.9% and 11%, respectively. The numbers-needed-to-treat to prevent one death were 29 and 34, respectively.
The crude incidences of bacteremia due to Staphylococcus aureus, non-fermenting Gram negative bacilli, and Enterobacteriaceae was significantly lower in SDD and SOD patients. Fifteen patients (0.8%) in SOC, five in SOD (0.3%), and nine (0.4%) in the SDD group had positive stool tests for Clostridium difficile toxin. Significant antibiotic resistance was not detected and, in fact, there were no patients with MRSA and only eight with VRE in rectal swabs in the entire study.
Commentary
This study demonstrates a small, but statistically significant benefit from the use of prophylactic regimens, as described in the Table. The lack of significantly different outcomes between SOD and SDD suggests that the four days of intravenously administered cefotaxime in the latter group plays no important beneficial role, and neither does the greater amount of topical antibiotic used in that group. Thus the six-hourly oropharyngeal application of a paste containing polymyxin E, tobramycin and amphotericin B, each in a 2% concentration, would appear to provide maximum benefit.
The major concern regarding the use of regimens such as this, however, is the certainty that the resultant selective pressure would eventually lead to the emergence of antibiotic-resistant bacteria. This was not, however, detected in this study. Performed in the Netherlands, which has a very low baseline frequency of isolation of antibiotic-resistant bacterial pathogens. In addition, the study was of short duration. A preferred alternative to the use of antibiotics for this purpose is the use of topical chlorhexidine, which has been demonstrated to prevent nosocomial infection in some ICU populations.1
Reference
- Segers P, et al. Prevention of nosocomial infection in cardiac surgery by decontamination of the nasopharynx and oropharynx with chlorhexidine gluconate: a randomized controlled trial. JAMA. 2006;296:2460-2466.
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content