Dear Editor, With great interest, I read Silvestri and coworkers’ review article [1] introducing the concept of ‘‘critical illness–related carriage in overgrowth concentrations (CIRCO)’’ as the leading mechanism behind what is called selective digestive tract decontamination (SDD). The authors don’t put much weight on the risk of resistance development shown in the Oostdijk study [2], however in an age when colistin is the only available antibiotic to treat some multiresistant Gram-negative organisms, some questions about the general use of the original SDD strategy with the entry criteria of ‘‘ventilatory support for more than 48 h’’ should be raised. De Smet’s [3] large multicenter trial also questions the necessity of the systemic antibiotic component, especially as third-generation cephalosporines are strongly associated with ESBL development [4]. Recently, Razazo and co-workers [4] demonstrated that many patients admitted to the medical ICU from the community are colonized with ESBL E. coli, but in the majority of cases nosocomial infections occur by other Gram-negative organisms in longer term ICU patients after a median of 9 days, and are mostly already found in rectal swabs. This study supports the concept of CIRCO and indicates that its diagnosis by regular surveillance cultures seems possible before infection occurs. In my clinical experience, a number of nonventilated patients show the described overgrowth patterns and develop nosocomial infections associated to these organisms, but many ventilated patient do not. Moreover, since the original introduction of SDD, the ventilatory support regimen has dramatically changed, including the intense utilization of noninvasive ventilation. Ventilatory care bundles including the use of oral care with antiseptic solutions have reduced the incidence of VAP. Early enteral nutrition has been the accepted standard promoting the integrity of the mucosal barrier, and most likely of the intestinal flora as well. Concepts have been introduced utilizing probiotics for the latter purpose [5]. This might be a reason why many practitioners, not only in the US, are still SDD skeptics. To translate the available evidence into the daily life of clinical practice, and as a concept for further clinical studies, I would like to introduce the following risk and CIRCO-diagnosisbased modified SDD concept in which patients with an anticipated ICU stay longer than 72 h need to be screened on admission and then once or twice a week, depending on unit characteristics: The modified SDD regimen, with enteral (given orally or via a feeding tube) tobramycin, colistin, and amphotericin B (add vancomycin if rectal swab is positive for MRSA) only, is used for critically ill patients after 72 h in the ICU if CIRCO (which would be defined as the presence of Klebsiella spp., Enterobacter spp., Citrobacter spp., Proteus mirabilis, Morganella morganii, Serratia marcescens, Acinetobacter baumannii or Pseudomonas aeruginosa in relevant quantity in the nasopharyngeal or rectal screening swabs) is already present on admission, or a change towards CIRCO evolves in continuous surveillance swabs, independently of whether they are receiving ventilatory support or not. In high-risk patients for early infections admitted to the ICU, e.g., patients with severe burns, severely immunocompromised patients defined as groups 2 and 3 by KRINKO [6], anastomotic leakage after esophageal, gastric, intestinal and pancreatic surgery, ileus, bowel ischemia, neurological or neurosurgical disease with increased ICP (especially when treated with hypothermia or barbiturate sedation), and those with femoral lines for ECMO, IABP or renal replacement therapy, the modified SDD regimen can be started on admission prophylactically without CIRCO diagnosis. The indication for continuous treatment should be evaluated weekly. With such a diagnosis-based concept we could utilize the benefits of SDD in those patients who are most likely profit from it, while avoiding unnecessary treatment in others, and also reduce the risk of unwanted ecological changes and resistance development.
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Jun 1, 2013
M Enany + 4
Open Access
