Decontamination: not so selective?

Remember the NEJM study from the Netherlands that compared selective digestive decontamination (SDD) vs. selective oropharyngeal decontamination (SOD) vs. placebo for infection prevention in ICU patients? The upshot, using 28 day mortality as an endpoint, was that both SDD and SOD were beneficial, but there was no evidence that one was better than another.

These investigators have now published a report on changes in antimicrobial resistance after the prophylactic use of antibiotics in this study (tobramycin, polymyxin E and amphotericin for oropharyngeal (SOD) or nasogastric (SDD) administration, and 4 days of IV cefotaxime (SDD)).

Surveillance of rectal and respiratory tract samples from patients in the 13 participating ICUs demonstrated that resistance to ceftazidime, tobramycin, and ciprofloxacin increased in GI tract flora after the SDD intervention and increased in respiratory flora after both SDD and SOD interventions.

I have to read the fine print more closely, but this confirms my view that we should stick with chlorhexidine oral care to suppress oropharyngeal flora, rather than SDD or SOD approaches that use therapeutic antibiotics.