Decreased transmission of Enterobacteriaceae with extended-spectrum beta-lactamases in an intensive care unit by nursing reorganization.

In our gastrointestinal surgical intensive care unit (SICU), the large number of patients with multiple enterostomies enhances the risk of nosocomial transmission of gut extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBLE) by health care workers. A control study performed in our SICU from June-August 1992 showed an ESBLE gut colonization rate of 70%. To reduce this rate, nursing procedures were intensified or modified, particularly handwashing, single-use equipment and waste control. To test the efficiency of these procedures, 64 patients hospitalized for more than two days from September 1992-March 1993 were screened for gut acquisition of ESBLE. Rectal samples were taken within 48 h after admission and then weekly. After nursing reorganization, the ESBLE colonization rate dropped significantly to 40% (P < 0.001). Twenty patients (31.7%) acquired a gut ESBLE, after a mean of 24.3 +/- 13.7 days. Each patient was colonized with one, two or three ESBLE (Klebsiella pneumoniae, Escherichia coli and Enterobacter aerogenes). Baseline characteristics of the 20 colonized and 39 non-colonized patients showed no significant difference (Student's t-test, P > 0.05). The nursing workload, estimated as a omega index, was greater in the colonized group (P < 0.001). These findings show that strict observance of nursing procedures can significantly reduce ESBLE acquisition in a high-risk surgical unit.