Incidence and susceptibility of pathogenic bacteria vary between intensive care units within a single hospital: implications for empiric antibiotic strategies.
BACKGROUND
The purpose of this study was to determine whether the incidence of recovery and patterns of antibiotic susceptibility of pathogenic bacteria vary between intensive care units (ICUs) in a single teaching hospital.


METHODS
Culture and susceptibility results were collected prospectively for a 3-month period (April through June 1999) in each of the surgical, trauma, and medical ICUs. The number of unique isolates and susceptibility patterns were determined. Susceptibility of isolates among ICUs was compared with chi2.


RESULTS
Statistically significant differences between ICUs in susceptibility to various antibiotics were found for Staphylococcus aureus, Enterococcus sp, Acinetobacter sp, Enterobacter sp, Klebsiella sp, and Pseudomonas sp. Notably, vancomycin-resistant Enterococcus was not seen in the medical ICU, whereas it was seen in both the surgical and trauma ICUs. Klebsiella spp resistant to ceftazidime were seen only in the trauma ICU. The aminoglycosides and quinolones had attenuated activity against Pseudomonas sp in the surgical ICU, whereas they remained highly effective in the trauma ICU. Cefazolin had no activity against the Enterobacter sp in either of the surgical ICUs, but was highly effective in the medical ICU.


CONCLUSIONS
Although the microbiologic results of this study should not be extrapolated to other institutions, the principle is of value. There is variability between ICUs in a single large teaching hospital in susceptibility of bacterial pathogens to various antibiotics. This may have implications in the design of empiric antibiotic strategies and the planning of the hospital formulary. Hospital wide or composite ICU antibiograms are inadequate for planning empiric therapy in the ICU.
Namias
N
N
University of Miami School of Medicine, Daughtry Family Department of Surgery, and Jackson Memorial Hospital, Florida 33101, USA.
Samiian
L
L
Nino
D
D
Shirazi
E
E
O'Neill
K
K
Kett
D H
DH
Ginzburg
E
E
McKenney
M G
MG
Sleeman
D
D
Cohn
S M
SM
D019072:Antibiotic Prophylaxis / Q000379:methods*; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control; D004352:Drug Resistance, Microbial; D005431:Florida / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D011446:Prospective Studies; D013530:Surgical Wound Infection / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control; D014946:Wound Infection / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control