A REAPPRAISAL OF THE ROLE OF GRAMS STAINS OF TRACHEAL ASPIRATES IN GUIDING ANTIBIOTIC SELECTION IN THE SURGICAL INTENSIVE-CARE UNIT

Background: Tracheal aspirate Gram's stains are used to guide antibiot ic selection in empiric pneumonia treatment in the surgical intensive care unit (SICU). We questioned,whether Gram's stains predict the orga nism cultured, Methods: A retrospective review of prospectively collec ted data. Results: Gram's stains correlated with the cultured organism in 284 of 543 (52%) SICU cultures and in 226 of 403 (56%) trauma inte nsive care unit (TICU) cultures, Gram-negative rod (GNR) stains yielde d GNR organisms in 182 of 205 (89%) SICU cultures and in 160 of 176 (9 1%) TICU cultures, Gram-positive coccus (GPC) stains yielded GPC organ isms in 75 of 228 (33%) SICU cultures and in 52 of 149 (35%) TICU cult ures, Noncorrelates in the GPC group were predominantly GNRs (185 of 2 50 (74%)). Conclusion: When the clinical decision has been made that e mpiric antibiotic coverage is necessary, GNR coverage should be instit uted regardless of Gram's stain result, The decision to institute GPC coverage needs to be supported by clinical data other than the Gram's stain.