Selective decontamination of the digestive tract in surgical patients - A systematic review of the evidence

Objective: To determine the comparative efficacy of selective decontaminati on of the digestive tract in critically ill surgical and medical patients, and in selected subgroups of surgical patients with pancreatitis. major bur n injury, and those undergoing major elective surgery and transplantation. Data Sources: The MEDLINE database was searched from January 1966 to Decemb er 1996 Using the terms "decontamination or prophylasis," "intensive care u nits," and "antibiotics," The search was limited to English-language studie s evaluating the efficacy of selective decontamination of the digestive tra ct in human subjects. Study Selection: The primary review was restricted to prospective randomize d trials. Data Extraction: End points of interest included rates of nosocomial pneumo nia, bacteremia, urinary tract infection, wound infection, mortality. and l ength of intensive care unit stay. Methodologic quality of individual studi es was assessed using a previously described model. Data Synthesis: Odds ratios (ORs) together with their (95% confidence inter val [CIs]) were reported and determined using the Mantel-Haenszel method. M ortality was significantly reduced with the use of selective decontaminatio n of the digestive tract in critically ill surgical patients (OR, 0.7; 95% CI, 0.52-0.93), while no such effect was demonstrated in critically ill med ical patients (OR, 0.91; 95% CI, 0.71-1.18). The greatest effect was demons trated in studies where both the topical and systemic components of the reg imen were used. Rates of pneumonia were reduced in both subsets of patients , while those of bacteremia were significantly reduced only in surgical pat ients. Conclusions: Selective decontamination of the digestive tract notably reduc es mortality in critically ill surgical patients, while critically ill medi cal patients derive no such benefit. These data suggest that the use of sel ective decontamination of the digestive tract should be limited to those po pulations in whom rates of nosocomial infection are high and in whom infect ion contributes notably to adverse outcome.