Selective Decontamination of the Digestive Tract (SDD): Is the Game Worth the Candle?

Selective decontamination of the digestive tract (SDD) is an infection prevention strategy in intensive care unit (ICU) patients by topical administration of antibiotics to the mouth and stomach to eradicate potentially pathogenic bacteria and yeast that may cause infections. It also includes a short course of intravenous antibiotics to treat incubating infections at the time of ICU admission. Several randomized, controlled studies, all performed in ICUs with low rates of antibiotic resistance, have shown that SDD prevents ventilator-associated pneumonia and improves survival. Surprisingly, SDD was also associated with lower rates of colonization with resistant gram-negative bacteria and no effect on methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Selective oral decontamination (SOD) consisting of oral antibiotics only, without systemic antibiotics or antibiotics given in the stomach, may also increase survival. In areas with low prevalence of MRSA and VRE, SDD should be considered the standard of care in ICUs. In countries where colonization with MRSA and VRE is frequent, resistance may increase, and SDD should be considered experimental therapy. Future research should focus on the effects of SDD compared with SOD on resistance and on SDD-like strategies in areas where MRSA and VRE are endemic.