Koch M, Coyne D, Hoppe-Bauer J, Vesely T M
Department of Internal Medicine, Division of Nephrology, Washington University School of Medicine, St. Louis - USA.
J Vasc Access. 2002 Jan-Mar;3(1):38-42. doi: 10.1177/112972980200300106.
Tunneled catheters serve as interim access during maturation of a graft or fistula, or as a permanent vascular access in those patients who have exhausted their traditional access sites. However, bacteremia rates are high in patients with chronic catheters and indiscriminate removal of catheters during bacteremia increases morbidity and costs. A method to identify whether a catheter was colonized with the offending bacteria, without requiring catheter removal is desirable. We compared endoluminal brushing and heparin aspiration, to detect catheter colonization, in 24 asymptomatic patients undergoing elective tunneled hemodialysis catheter removal. The incidence of catheter colonization was highly correlated with catheter duration of inverted exclamation markY 30 days (p=0.03). Staphylococcus epidermidis represented 68% of the organisms isolated. No other organism accounted for more than 7% of the total. Fifteen (62.5%) of the 24 catheters had positive cultures. Eleven of the catheters were positive by culture of heparin aspirate and eight were positive by endoluminal brushing. Only four of the catheters were positive by both methods. The arterial lumen was more likely to have positive cultures than the venous lumen using either method. In this prospective investigation of tunneled hemodialysis catheters in asymptomatic patients we have demonstrated that a heparin aspirate sample is more likely to detect catheter colonization than a sample obtained using an endoluminal brush. Furthermore, 75% of catheters present for more than 30 days were colonized. Further study is needed to determine if the heparin aspirate method could be used in patients with bacteremia to accurately identify catheters that need removal.
隧道式导管可在移植物或动静脉内瘘成熟期间作为临时通路，或在那些传统通路部位已用尽的患者中作为永久性血管通路。然而，慢性导管患者的菌血症发生率很高，且在菌血症期间不加区分地拔除导管会增加发病率和成本。因此，需要一种无需拔除导管就能识别导管是否被致病细菌定植的方法。我们比较了腔内刷检和肝素抽吸法在24例接受择期隧道式血液透析导管拔除的无症状患者中检测导管定植的情况。导管定植的发生率与导管留置时间超过30天高度相关（p=0.03）。表皮葡萄球菌占分离出的微生物的68%。没有其他微生物占总数的比例超过7%。24根导管中有15根（62.5%）培养结果为阳性。其中11根导管通过肝素抽吸培养呈阳性，8根通过腔内刷检呈阳性。只有4根导管两种方法检测均为阳性。无论采用哪种方法，动脉腔的培养阳性率都比静脉腔更高。在这项对无症状患者的隧道式血液透析导管的前瞻性研究中，我们证明肝素抽吸样本比腔内刷检样本更有可能检测到导管定植。此外，留置超过30天的导管中有75%被定植。需要进一步研究以确定肝素抽吸法是否可用于菌血症患者，以准确识别需要拔除的导管。
