Of 21112 blood culture vials processed on a one year and half periods, 2959 vials including 2063 blood specimen, 885 pericardial fluids and 11 body fluids had positive results from 1 January 2000 through 30 June 2001. The five most common isolates were Coagulase negative Staphlococcus spp. (1084 vials), Staphylococcus aureus (452 vials), Escherichia coli (418 vials), Klebsiela pneumonia (190 vials) and Gram positive bacillus (115 vials). The authors analyzed organisms recovered daily during the seven-day cycle of testing and compared isolates recovered on days 6 and 7. Only 8 of the first five days testing:23 and 3 vials (0.8 and 0.1%) were positive on day 6 and 7. Only 8 of the latter vials were judged to contain significant strains: three Klebsiella pneumoniae (127-142 hr), two Staphylococcus aureus non-enterococcus (130 hr). The data suggested that the clinical bebefit of testing on days 6 and 7 does not justify its cost in our patient population.
