Thursday January 24, 2008
Selective digestive decontamination (SDD) - a controversy !
Selective digestive decontamination (SDD) has been used as a prophylactic measure to prevent nosocomial infections in critically ill patients. But it continues to remain controversial.
Arguments against: wide spread use of this strategy are the fear of emergence of multi-resistance organisms and its cost.
Arguments in favour: is the reference of availability of 54 randomized, controlled trials with seven meta-analyses showing a significant reduction of infectious morbidity and mortality 1. Also, there are evidences that fear of wide spread emergence of multi-resistance organisms is OVER-EXAGGERATED 2, 3. The newer, even more potent systemic antimicrobials fail to clear MRSA and Pseudomonas aeruginosa from the gut, because the salivary and fecal concentrations are not lethal. The addition of enteral antimicrobials probably eliminates the source, controlling resistant mutants in the gut flora.
Very recent updated International guidelines for management of severe sepsis and septic shock from Surviving Sepsis Campaign recommends not to use of SDD specifically in severe sepsis. But please note that the guidelines group was evenly split on the issue of SDD, with equal numbers in favor and against recommending the use of SDD. The final consensus on use of SDD in severe sepsis was achieved only at the last nominal committee meeting 4.
Out of many recommended regimens, one is a combination of oral and enteral polymyxin E, tobramycin and amphotericin B four times daily until discharge from the ICU. In addition, an initial four-day course of iv cefotaxime was given. When applicable, antibiotic paste and suppositories were used for tracheostomy sites and blind-bowel loops respectively. Finally, nebulized polymyxin E or amphotericin B was administered to eradicate documented colonization of the tracheobronchial tree 2.
References: click to get abstract / article if available
1. Antibiotic prophylaxis to reduce respiratory tract infections and mortality in adults receiving intensive care (Cochrane Review). In: The Cochrane Library, issue 1. Chichester, John Wiley & Sons, 2004
2. Selective digestive decontamination decreases mortality and morbidity in the intensive care - Canadian Journal of Anesthesia 51:737-739 (2004)
3. Surviving Sepsis Campaign Guidelines: Selective Decontamination of the Digestive Tract Still Neglected - letter to editor, Critical Care Medicine:Volume 33(2)February 2005pp 462-463
4. Surviving Sepsis Campaign: International guidelines for management of severe sepsis and septic shock: 2008 - Critical Care Medicine:Volume 36(1)January 2008pp 296-327