Hull Garret J, Moureau Nancy L, Sengupta Shramik
1 Cook Medical, Bloomington, Indiana - USA.
2 PICC Excellence, Inc, Hartwell, GA; Greenville Memorial Hospital, Greenville, SC; Adjunct Associate Professor, Alliance for Vascular Access Teaching and Research (AVATAR) Group, Centre for Health Practice Innovation, Menzies Health Institute Queensland, Griffith University, Brisbane - Australia.
J Vasc Access. 2018 Jan;19(1):12-22. doi: 10.5301/jva.5000781.
Blood reflux is caused by changes in pressure within intravascular catheters upon connection or disconnection of a syringe or intravenous tubing from a needle-free connector (NFC). Changes in pressure, differing with each brand of NFC, may result in fluid movement and blood reflux that can contribute to intraluminal catheter occlusions and increase the potential for central-line associated bloodstream infections (CLABSI).
In this study, 14 NFC brands representing each of the four market-categories of NFCs were selected for evaluation of fluid movement occurring during connection and disconnection of a syringe. Study objectives were to 1) theoretically estimate amount of blood reflux volume in microliters (μL) permitted by each NFC based on exact component measurements, and 2) experimentally measure NFC volume of fluid movement for disconnection reflux of negative, neutral and anti-reflux NFC and fluid movement for connection reflux of positive displacement NFC.
The results demonstrated fluid movement/reflux volumes of 9.73 μL to 50.34 μL for negative displacement, 3.60 μL to 10.80 μL for neutral displacement, and 0.02 μL to 1.73 μL for pressure-activated anti-reflux NFC. Separate experiment was performed measuring connection reflux of 18.23 μL to 38.83 μL for positive displacement NFC connectors.
This study revealed significant differences in reflux volumes for fluid displacement based on NFC design. While more research is needed on effects of blood reflux in catheters and NFCs, results highlight the need to consider NFCs based on performance of individual connector designs, rather than manufacturer designation of positive, negative and neutral marketing categories for NFCs without anti-reflux mechanisms.
血液反流是由于在将注射器或静脉输液管与无针接头（NFC）连接或断开时，血管内导管内压力发生变化所致。压力变化因NFC的每个品牌而异，可能导致液体流动和血液反流，这可能会导致管腔内导管堵塞，并增加中心静脉导管相关血流感染（CLABSI）的可能性。
在本研究中，选择代表NFC四个市场类别的14个NFC品牌，以评估在连接和断开注射器期间发生的液体流动。研究目标是：1） 根据精确的组件测量值，从理论上估计每个NFC允许的微升（μL）血液反流体积；2） 通过实验测量负位移、中性和抗反流NFC断开反流的NFC液体流动体积，以及正位移NFC连接反流的液体流动体积。
结果表明，负位移的液体流动/反流体积为9.73μL至50.34μL，中性位移为3.60μL至10.80μL，压力激活抗反流NFC为0.02μL至1.73μL。进行了单独的实验，测量正位移NFC连接器的连接反流为18.23μL至38.83μL。
本研究揭示了基于NFC设计的液体位移反流体积存在显著差异。虽然需要对导管和NFC中血液反流的影响进行更多研究，但结果强调需要根据单个连接器设计的性能来考虑NFC，而不是根据没有抗反流机制的NFC的正、负和中性营销类别制造商指定。
