Antibiotic susceptibility in the surgical intensive care unit compared with the hospital-wide antibiogram.
OBJECTIVE
To compare the antibiotic susceptibility of bacterial isolates from patients in the surgical intensive care unit (SICU) with hospital-wide bacterial susceptibility.


METHODS
Retrospective cohort analytic study.


METHODS
Eight-bed SICU in a university-affiliated teaching hospital.


METHODS
All hospitalized patients with culture results positive for microorganisms.


METHODS
None.


METHODS
Antibiotic susceptibility data were collected retrospectively for all bacterial isolates from SICU patients during July 1, 1994, to June 30, 1995. All duplicate and surveillance cultures were eliminated from the data set. Susceptibility testing was conducted using our standard laboratory methods. Results were compared with the hospital-wide antibiogram (HWA) for the same time period. Comparisons were made using the chi(2) test with Yates correction or the Fisher exact test, as appropriate. Staphylococcus aureus (HWA, n=494; SICU, n=71) was significantly less susceptible to oxacillin (51% vs 28%; P<.001), ciprofloxacin (50% vs 25%; P<.001), erythromycin (46% vs 23%; P<.001), and clindamycin (51% vs 27%; P<.001) in the SICU. Coagulase-negative staphylococci (HWA, n=339; SICU, n=37) were significantly less susceptible to oxacillin (33% vs 16%; P=.04) and clindamycin (57% vs 34%; P=.02). Pseudomonas aeruginosa (HWA, n=513; SICU, n=96) was less susceptible to imipenem (85% vs 74%, P=.01) and more susceptible to ticarcillin-clavulanic acid (88% vs 100%, P<.001) in the SICU. Escherichia coli (HWA, n=474; SICU, n=36) was more susceptible to most penicillin-derivative antibiotics in the SICU (ampicillin [68% vs 83%, P=.06], ticarcillin [65% vs 86%, P=.01], mezlocillin [76% vs 95%, P=.01], and ticarcillin-clavulanic acid [88% vs 100%, P=.02]).


CONCLUSIONS
The 2 most commonly isolated bacterial pathogens in the SICU (S aureus and P aeruginosa) had significantly different susceptibility patterns compared with the HWA. Surprisingly, E coli isolated in the SICU tended to be more susceptible to penicillin-derivative antibiotics. These data indicate that empiric antibiotic choices in the SICU may be better guided by unit-specific antibiograms.
Kaufman
D
D
Department of Surgery, Rochester General Hospital, NY 14621-3095, USA.
Haas
C E
CE
Edinger
R
R
Hollick
G
G
D015331:Cohort Studies; D006761:Hospitals; D006801:Humans; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D012189:Retrospective Studies