血液透析装置与供水回路连接端聚氯乙烯软管管道细菌生物膜研究

目的了解血液透析装置与供水回路连接端聚氯乙烯软管管道细菌生物膜形成情况,开展水处理系统细菌生物膜控制的策略性研究。方法按照软管使用年限、材质不同分为A、B两组,A组为使用7年的透明软管,B组为使用5年的红色不透明软管,再对A、B两组标本进行不同的实验处理(A_1、B_1组不做任何处理;A_2、B_2组:过氧化氢消毒剂浸泡20 min;A_3、B_3组:采用无菌棉拭子搅拌软管内壁,过氧化氢消毒剂浸泡20 min),最后在电镜下观察细菌生物膜状态。结果 A_1组显示有层层叠加、连接网状的生物膜形成;A_2、A_3组显示细菌生物膜有缝隙裂缝,未能完全脱落。B_1组平面突起的团块即为细菌生物膜;B_2组显示存在散在的球状体;B_3组显示存在游离的棒状细菌体。A组软管(不做任何实验处理)行不同倍数电镜扫描,显示主要由成簇生长的杆菌构成。结论细菌生物膜的清除效果与其形态结构的复杂性、叠加程度存在很大的相关。研究血液透析装置与供水回路连接的软管材料、细菌生物膜形成的时间点及消毒处理方法等,可以更好地进行水处理系统细菌生物膜的控制策略性研究。

Bacterial biofilm of polyvinyl chloride hose pipeline at the connection end of hemodialysis device and water supply loop

Objective To understand the formation of bacterial biofilm in polyvinyl chloride(PVC) hoses pipeline at the connection end of hemodialysis device and water supply loop, and control bacterial biofilm in water treatment system. Methods The hoses were divided into two groups(group A and B) according to their service life and material, group A was transparent hoses used for 7 years and group B was red opaque hoses used for 5 years, specimens of group A and B were conducted different experimental treatment (group A₁ and B₁ didn't undergo any treatment; group A₂ and B₂ immersed in hydrogen peroxide disinfectant for 20 minutes; group A₃ and B₃:the inner wall of hoses were stirred with sterile cotton swabs and immersed in hydrogen peroxide disinfectant for 20 minutes), bacterial biofilm was observed under electron microscope. Results Group A₁ showed formation of overlapped and reticulated biofilm; group A₂ and A₃ showed that there were fissure and crack in bacterial biofilm, which could not completely fall off. In group B₁, the planar bulges were bacterial biofilm; group B₂ showed scattered globules; group B₃ showed the presence of free rod-like bacteria. Group A hoses (without any experimental treatment) were scanned by electron microscope at different multiples, showing that they were mainly composed of clustered bacteria. Conclusion The removal efficiency of bacterial biofilm is closely related to the complexity and overlapping degree of its morphology and structure. The study on hose material, time point of bacterial biofilm formation and disinfection treatment method for the connection of hemodialysis device and water supply loop can better carry out the control strategy research of bacterial biofilm in water treatment system.