Selective digestive decontamination is superior to selective oropharyngeal decontamination

are interested in the debate on the effi cacy and safety of selective digestive decontamination (SDD) and selective oropharyngeal decontamination (SOD) raised by Schultz and Haas in their review [1]. Th e authors concluded that 'SDD and SOD are equally eff ective with respect to the prevention of mortality' [1]. Th is statement is based on the results of a Dutch randomized controlled trial [2], which was the fi rst to demonstrate a survival benefi t of SOD. However, the mortality reduction was higher, albeit not signifi cantly, in the SDD group than in the SOD group. Additionally, a recent meta-analysis, including nine SOD randomized controlled trials and 4,733 patients, failed to show any signifi cant mortality reduction (odds ratio (OR) = 0.93; 95% confi dence interval (CI) = 0.81 to 1.07) [3]. In contrast , there is robust evidence indicating that SDD including parenteral and enteral antimicrobials signifi cantly reduces mortality [4]. Th e authors wrote that 'whether SDD or SOD are favorable with regard to development of antibiotic resistance is yet unknown' [1]. Th e Dutch randomized controlled trial, however, showed that patients with aerobic Gram-negative bacilli in rectal swabs resistant to the marker antibiotics numbered less with SDD than with SOD [2]. Additionally, bacteremia due to highly resistant patho gens was signifi cantly reduced by SDD compared with SOD (OR = 0.37, 95% CI = 0.16 to 0.85), and lower respira tory tract colonization due to highly resistant pathogens was lower with SDD (OR = 0.58, 95% CI = 0.43 to 0.78) than with SOD (OR = 0.65, 95% CI = 0.49 to 0.87) compared with standard care [5]. We believe that SDD is superior to SOD in terms of both mortality reduction and emergence of resistance. Competing interests The authors declare that they have no competing interests. References 1. Schultz MJ, Haas LE: Antibiotics or probiotics as preventive measures against ventilator-associated pneumonia: a literature review. Crit Care oropharyngeal chlorhexidine to prevent pneumonia and to reduce mortality in ventilated patients: which manoeuvre is evidence-based? A: Survival benefi t of the full selective digestive decontamination regimen. Eff ects of selective digestive and selective oropharyngeal decontamination on bacteraemia and respiratory tract colonization with highly resistant microorganisms [abstract].