Appropriateness of antibiotic prescribing after transition from an open to a closed intensive care unit

The main aim of the study was to investigate whether transition from an open to a closed intensive care unit would improve outcome in critically ill patients through more appropriate antibiotic prescribing.

A retrospective chart survey was performed of all sputum and blood cultures taken after more than 48 hours of ICU stay over a 3-month period before (period 1) and a 3-month period after (period 2) transition from an open to a closed intensive care unit. Populations in both periods were compared for age, sex, APACHE scores and the following outcome variables: ICU mortality, average length of stay, percentage appropriate and inappropriate changes in antibiotic therapy, percentage appropriate and inappropriate non-changes in antibiotic therapy, average reporting delays of culture results. Antibiotic therapy was deemed appropriate when the patients showed signs of sepsis, severe sepsis or septic shock according to the ACCP/ACCM criteria and were prescribed antibiotics to which the cultured organisms were fully sensitive. Differences between means of continuous variables were tested by the Student t-test and between percentages by the method as described by Armitage [1]. A P value of less than 0.05 was considered statistically significant.

There was a trend towards an increased percentage of inappropriate decisions in period 2 vs period 1 (13% vs 9%) although this did not reach statistical significance (see Table).There were no differences in APACHE scores, length of stay or mortality between period 1 and 2.

Table

Statistically significant increased reporting delays prior to inappropriate decisions not to change antibiotic therapy compared to reporting delays prior to appropriate decisions to change antibiotic therapy were found in period 1 but not in period 2 (see Table). Transition from an open to a closed intensive care unit did not lead to better antibiotic prescribing or outcome in ICU patients. Whereas in the open ICU period inappropriate antibiotic therapy was due to a combination of delays in reporting of culture results as well as inappropriate decisions, in the closed period this was solely due to inappropriate decisions not to change antibiotics.