Impact of the resin blood culture medium on the treatment of critically ill patients

OBJECTIVE To assess the relevance, both clinical and bacteriologic, of the use of resin-containing blood culture media in blood cultures taken from critically ill patients receiving antibiotics. DESIGN A prospective, open clinical trial. SETTING The mixed medical surgical intensive care unit (ICU) of a 550-bed urban hospital. PATIENTS All ICU patients admitted during a 3-month period (n equals 49) with suspected sepsis requiring blood cultures as part of their laboratory investigations. INTERVENTIONS The use of an aerobic resin-containing blood culture medium, in addition to the regular aerobic and anaerobic media for all blood cultures taken. MEASUREMENTS AND MAIN RESULTS Each blood culture result was classified as to its clinical significance. Changes in patient management were recorded. Culture sets in which the resin-containing bottle provided the information central to the change in patient management were identified. Bacteriologically, the results from the resin-containing medium were compared with the results from the aerobic and anaerobic media. Of 266 blood culture sets, 103 (39%) were positive, growing 278 bacterial and fungal isolates. Clinically, the resin-containing medium alone provided relevant data leading to changes in patient management on three occasions. On two of these occasions, cultures from the regular media provided the same data within 72 hrs. Bacteriologically, 77 (29%) aerobic bottles, 55 (21%) anaerobic bottles, and 89 (33%) resin-containing bottles were positive (statistical comparison of percentagesaerobic vs. resin-containing bottles, nonsignificant; aerobic vs. anaerobic bottles, p less than .046; anaerobic vs. resin-containing bottles, p less than .0027). A similar proportion of pathogens was isolated from the resin-containing bottles only (9%) and aerobic bottles only (6%). A higher proportion of contaminants was isolated from the resin-containing bottles only than the aerobic bottles only in the various sets (17% vs. 7%, p less than .046). The resin-containing bottle showed a trend toward increased detection of Staphylococcus aureus and Pseudomonas aeruginosa bacteremia. CONCLUSIONS The resin-containing medium offers little clinical benefit to the majority of ICU patients. Bacteriologically, it seems to have a similar overall sensitivity as the regular aerobic medium (with the possible exception of a higher sensitivity for the isolation of S. aureus and P. aeruginosa), but a lower specificity. The wide-spread use of the