Active Surveillance Cultures on Admission to ICU Does Not Affect Hospital Length of Stay

Active Surveillance Cultures on Admission to ICU Does Not Affect Hospital Length of Stay

Scott Norville, MD, Charlotte Luce, RN, Melicia Brown, MPH, Calvin White, MPH JPS Health Network, Fort Worth, TX

Background: Two contradictory points of view have prevailed in discussions of  ASC (active surveillance culturing): hospital-acquired infections have been known to extend the stay of hospitalized patients, while conversely, studies have also shown that contact isolation has had the effect of decreasing the therapeutic contact of health care providers with patients, therefore potentially also increasing the length of stay.

Objective: to ascertain the effect of ASC on length of stay in an acute care general hospital.

Methods: Retrospective data are reviewed; a primary listing of patients who had surveillance cultures of the nares was retrieved from the microbiology laboratory. This was correlated to add admission and length of stay data. Samples from patients who were not admitted as inpatients or who had admissions shorter than three days were excluded, as these were primarily patients undergoing outpatient surgeries or were hospitalized for too short a period for the surveillance cultures to have resulted in the institution of contact isolation. ASC is actively pursued on every admission and transfer to the ICU (which includes medical, general surgical and trauma); elsewhere in the hospital surveillance culturing is used on an ad hoc basis. Data on LOS specifically in the ICU was also available for 2008-2009.

Results: 855 cultures were indicated as nasal, from February, 2008 through October 2010. Of these 181 were excluded as above. Of the remainder, 474 were positive for MSSA and 200 for MRSA. The range of LOS was three days to 253, mean LOS was 12.92 for MRSA and 12.87 for MSSA. Median was 8 days for both groups. Comparison of these ranges showed no statistical difference using Mann-Whitney analysis (p=0.5875). Analysis of ICU LOS showed no significant decrease during the study period (Spearman rank correlation, p=0.2728).

Conclusions: In our institution, use of contact isolation for MRSA colonization did not result in any change in length of stay for individual patients, when compared to patients colonized with non-resistant S. aureus. In other analysis we show a significant decrease in MRSA hospital-acquired infections with institution of the MRSA bundle in the ICU as well, but insufficient data to show a decrease in LOS.