Nair Neeraja A, Sirur Freston Marc, Krishnan S Vimal
Department of Emergency Medicine, Kasturba Medical College, Manipal, Manipal Academy of Higher Education (MAHE), Manipal, Udupi, Karnataka, India.
Int J Emerg Med. 2024 Nov 28;17(1):181. doi: 10.1186/s12245-024-00762-7.
Inferior vena cava (IVC) diameter measurement using ultrasound for volume status assessment has shown satisfactory results and is being adopted in Emergency and critical care settings. IVC diameter can vary depending on the cardiac function, respiratory efforts, intraabdominal pressure, and mechanical ventilation. Due to these factors, IVC measurement cannot be considered a stand-alone technique appropriate for every patient. The femoral vein (FV), a more superficial vein than IVC, can be considered an alternative method for assessing fluid responsiveness in patients presenting to the Emergency department. It is easily accessible and can be used in scenarios where IVC cannot be visualized or reliable.
This was a single-center diagnostic study where 85 patients who presented to the ED with chest pain were enrolled prospectively. IVC and femoral vein collapsibility indices, stroke volume, and cardiac output are measured using an ultrasound machine. The measurements were repeated after a passive leg-raising test. These values were compared with each other to assess an intra-class correlation between IVC and femoral vein collapsibility indices. We have also evaluated the relationship between the collapsibility indices of both veins and cardiac output.
DISCUSSION & LIMITATIONS: Our findings show an insufficient correlation between IVC and FV collapsibility indices. However, both vein diameters significantly increased after passive leg raising (PLR), indicating a response to fluid challenge. Post-PLR reduced IVC, and FV collapsibility index (CI) suggests intravascular volume expansion after a fluid challenge, also reflected in the hemodynamic parameters. Our study was conducted only in a subset of relatively stable patients. The applicability of the study in different subsets of patients presenting to ED is still questionable.
We conclude that femoral vein indices may not be an accurate alternative for volume assessment in the chosen cohort of patients. IVC and FV metrics do not correlate and may not be accurate for volume responsiveness. We may need to explore the utility of FV and its indices in a larger population in multiple settings for a better understanding of its role in volume assessment and responsiveness.
(EC/NEW/INST/2021/1707). Registered 03 January 2023.
使用超声测量下腔静脉（IVC）直径以评估容量状态已显示出令人满意的结果，并正在急诊和重症监护环境中得到应用。IVC直径会因心功能、呼吸努力、腹内压和机械通气而有所不同。由于这些因素，IVC测量不能被视为适用于每个患者的独立技术。股静脉（FV）是比IVC更浅表的静脉，可被视为评估急诊科患者液体反应性的替代方法。它易于触及，可用于无法可视化IVC或IVC不可靠的情况。
这是一项单中心诊断研究，前瞻性纳入了85例因胸痛就诊于急诊科的患者。使用超声仪测量IVC和股静脉的塌陷指数、每搏量和心输出量。在被动抬腿试验后重复测量。将这些值相互比较，以评估IVC和股静脉塌陷指数之间的组内相关性。我们还评估了两条静脉的塌陷指数与心输出量之间的关系。
我们的研究结果显示IVC和FV塌陷指数之间的相关性不足。然而，被动抬腿（PLR）后两条静脉直径均显著增加，表明对液体挑战有反应。PLR后IVC和FV塌陷指数（CI）降低表明液体挑战后血管内容量扩张，这也反映在血流动力学参数中。我们的研究仅在一部分相对稳定的患者中进行。该研究在急诊科不同患者亚组中的适用性仍值得怀疑。
我们得出结论，在所选患者队列中，股静脉指数可能不是容量评估的准确替代方法。IVC和FV指标不相关，可能对容量反应性不准确。我们可能需要在更多环境中的更大人群中探索FV及其指数的效用，以更好地了解其在容量评估和反应性中的作用。
（EC/NEW/INST/2021/1707）。2023年1月3日注册。
