Prevention of nosocomial infection in critically ill patients by selective decontamination of the digestive tract

Abstract

To evaluate the effect of a method of Selective Decontamination of the Digestive Tract (SDD) on colonization, nosocomial infection (NI), bacterial resistance, mortality and economic costs. Randomized, double blind, placebo controlled study. Polyvalent intensive care unit (ICU) of a tertiary care hospital with 27 beds. 101 patients with > 3 days of mechanical ventilation and > 5 days of stay, without infection at the start of the study. 47 belonged to the Treated Group (TG) and 54 to the Placebo Group (PG). The TG was given Cefotaxime i.v. (6 g/day) for the first four days and an association of Polymyxin E, Tobramycin and Amphotericin B at the oropharyngeal and gastrointestinal level throughout the whole stay. In the TG, colonization by gram-negative agents at oropharyngeal, tracheal and gastrointestinal level fell significantly. There was a significant drop in the overall, respiratory and urinary NI (26% vs 63%, p < 0.001; 15% vs 46%, p < 0.001; 9% vs 31%, p < 0.01). The overall mortality and NI related mortality was less in the TG (21% vs 44%, p < 0.05; 2% vs 20%, p < 0.01). The economic costs, mechanical ventilation time and length of stay were similar. The percentage of bacterial isolations resistant to Cefotaxime and Tobramycin was greater in the TG (38% vs 15% and 38% vs 9%, p < 0.001). colonization by gram-negative bacilli, NI and the mortality related to it can be modified by SDD. Continuous bacteriological surveillance is necessary.