无针接头，顾名思义，是一种输液接头，为了避免使用钢针将输液管和留置针连接或者用于多条输液管之间的连接。它的目的是避免了使用钢针带来的针刺伤和接触到血液体液等职业暴露风险。连接在留置针导管座后部的无针接头在留置期间还是关闭输液通道，防止微生物等外界异物进入血管的重要屏幛。
目前的无针接头按工作原理分，主要两大类：机械阀式和分隔膜式。市场上还有塑料钝针式，但使用得很少了。 机械阀式接头内部结构相对复杂，液体通道曲折狭窄，不少接头设计成很多接头都是不透明的。有的研究怀疑由于设计的原因会引起细菌在内部生长定殖。
前面老师们提到了正压接头，这是指，当连接输液接头的注射器等装置脱开接头时，留置针或者输液管内的液体是被往前推（血管方向），是往后流，还是不动。因为输液接头内部本身并不会自己产生压力，所以正压／负压的叫法是不准确的。 准确的叫法是正位移，负位移和零位移，这也是国际上通用的叫法。
老师们提到了可来福接头。可来福是ICU Medical公式生产的CLAVE系列接头的名字。但是要注意的是这家公司不是所有的接头都是正位移（正压）的。要和厂家核实。其它公司也一样。很多公司都生产多种接头。
越来越多的无针接头，特别是正位移（正压）接头进入市场。这些接头和血流相关感染的关系也成了研究热点。 学术期刊上有多篇文章研究血流相关感染的增加是否和使用了正位移接头或机械阀式接头。有关的讨论持续了很久也没结论。FDA在2010年8月发通知说，目前还没有足够信息表明这样的相关性。但是FDA要求所有生产正位移接头的厂家进行售后跟踪调查，同时要求报告相关不良反应。 FDA提醒采用机械阀式正位移接头前要仔细研究可能的风险，益处，并做好正确使用的培训。
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Positive Displacement Needleless Connectors and Bloodstream Infections: Initial Communication
Date Issued: August 11, 2010
Audience: Health Care Professionals
Medical Specialty: Infection Control
Summary of Issue and Scope:
Several peer-reviewed clinical studies report an increase in bloodstream infections following the introduction and use of positive displacement needleless connectors in healthcare facilities, as well as a reduction in infections after changing to another type of needleless connector. However, there is insufficient information to determine the magnitude of the risk of bloodstream infections with these devices as compared with other needleless connectors, or to determine whether the risk is associated with some or all positive displacement needless connectors. FDA is ordering post-market surveillance to better understand the risk of bloodstream infections from use of positive displacement needleless connectors.
Device:
A positive displacement needleless connector is part of a needleless system used for intravascular access. These devices may also be referred to as “luer activated valves,” “connectors,” or “accesses,” and may refer to “positive pressure” or “positive displacement” in their product descriptions.
Recommendations to Healthcare Professionals:
In 2008, two professional societies issued guidelines to minimize the risk of hospital acquired infections (http://www.journals.uchicago.edu/toc/iche/2008/29/S1). Those guidelines state, “Do not routinely use positive-pressure needleless connectors with mechanical valves before a thorough assessment of risks, benefits, and education regarding proper use.” The FDA’s initial evaluation supports this recommendation.
Postmarket Surveillance Studies
FDA is requiring companies that manufacture positive displacement needleless connectors to conduct postmarket surveillance studies. The studies will help clarify the infection risk associated with these devices and define more precisely their risks and benefits. Manufacturers will be required to collect data on bloodstream infections in patients who received their devices compared to patients who received other types of needleless connectors. More details can be found in FDA’s letter to infection control professionals.
Reporting Problems to FDA:
Prompt reporting of adverse events can help FDA identify and better understand the risks associated with medical products. If you suspect problems with the use of positive displacement needleless connectors, we encourage you to file a voluntary report through MedWatch, the FDA Safety Information and Adverse Event Reporting program. Healthcare personnel employed by facilities that are subject to FDA's device user facility reporting requirements should follow the reporting procedures established by their facilities.
Health care providers are also encouraged to notify their facility’s infection control personnel if they suspect a positive displacement needleless connector contributed to a bloodstream infection. |
发表于 2012-5-17 12:56
发表于 2012-5-17 14:46
