Inefficiency in 6-Set Requests for Blood Culture Analysis of Cancer Patients with the Central Venous Catheter

ABSTRACT

BACKGROUND: A central venous catheter (CVC) is commonly used for administering chemotherapy to cancer patients. The institutional guideline of the Gyeongsang National University Hospital (GNUH) for blood culture analysis of indwelling CVC patients recommended 6 sets (2 from the periphery and 4 from each lumen). We analyzed the usefulness of this guideline, because complying with this recommendation requires an abundant amount of the sample and it is both inconvenient and expensive. METHODS: Adult patients (age > or =18 yr old) who were admitted to the cancer center of GNUH between January 2011 and April 2012 were requested to have their blood culture analysis done. The positive rate, contamination rate, and distribution of microorganisms were compared according to the number of requested sets. The positive results of the stipulated 6 sets were analyzed. RESULTS: A total of 5,263 blood cultures were analyzed during the study period; of them, 74.4% were requests of 2 sets and 20.0% were requests of 6 sets. The positive rates in 2 set requests and 6 set requests were 8.0% and 14.3%, respectively (P<0.001). The requests for 6 sets were repeated about 5 times. All 6 sets showed positive in 16 cases (9.1%), whereas a part of the 6 sets was positive in 18 cases (10.3%). CONCLUSIONS: Although the positive rate was relatively high in the 6 set-requested groups, they had to be repeatedly requested. Microbial growth in a part of the 6-set requests was observed in a very small proportion (10.3%) of the patients, indicating that the benefit of blood culture of 6 sets is very low.