污染的血液培養會影響醫師對血流感染判定及抗生素使用。本研究收集2009年4月至2010年11月於某醫學中心急診室需作血液培養之595位病患，將皮膚典酒消毒時間隨機分為30秒及2分鐘，兩組各收集381套血液培養檢體（研究樣本），視兩消毒時間對血液培養污染率影響；並比較不同採血人員在香同病患間其血液培養污染率相關性。結果發現研究組中不論30秒及2分鐘，各有一套血液培養檢體污染，污染率皆為0.26%，皮膚碘酒消毒時間不因時間長短而有顯著差異性(P=1.00)。而在急診室抽血小組針對相同病患所抽取981套檢體（非研究樣本），其中有23套污染，污染率為2.34%；顯示不同採血人員組別所抽取血液培養污染率有其差異性(P<0.05)。血液培養其檢驗採檢的時機、套數、部位的消毒以及血瓶的消毒過程，都會影響細菌分離結果的正確性；採檢人員需具良好的採血技術及無菌觀念，降低血液培養污染率，提供醫師正確細菌培養結果。

Contaminated blood culture affects physicians' bloodstream infection judgment and antibiotics use. The study collected 595 patients who required performing blood culture in the emergency room of a medical center from April 2009 to November 2010. The procedures of iodine disinfection of the skin divided into two groups (30 seconds and 2 minutes), randomly collecting 381 blood culture specimens individually (research samples). According to above classification, we could observe their effects on blood culture contamination rate and compare the correlation of the blood culture contamination rate with different phlebotomists caring for the same patient. The results showed that two groups, whether 30 seconds and 2 minutes, had one set of blood culture specimen contamination (contamination rate, 0.26%). As a result, iodine disinfection on skin period was not the main reason of blood culture contamination (P=1.00). However, 981 blood culture sets from the sample patients (non-research samples) were collected by ER staffs, of which 23 sets were contaminated, and the contamination rate was 2.34%. It indicated that the blood culture contamination rates were different between different phlebotomists (P<0.05). Some factors will affect the accuracy of the bacterial isolation result, including collection timing, quantity of blood culture set, position disinfection and disinfection procedure of the blood culture bottles, thus phlebotomists require skillful technique and sterilization conception to decrease blood culture contamination rate and provide doctor correct bacterial culture results .