UO Nefrologia, Azienda Ospedaliera-Universitaria Parma, Via Gramsci 14, 43126, Parma, Italy.
Scuola di Specializzazione in Nefrologia, Dipartimento di Medicina e Chirurgia, Università di Parma, Parma, Italy.
J Nephrol. 2020 Feb;33(1):109-117. doi: 10.1007/s40620-019-00659-2. Epub 2019 Nov 15.
Accelerated muscle wasting still represents a major issue in critically ill patients. However, a key problem in the intensive care unit is the lack of adequate tools for bedside evaluation of muscle mass. Moreover, when acute kidney injury (AKI) coexists, fluid overload and/or rapid fluid shifts due to renal replacement therapies that frequently occur and may interfere with muscle mass assessment. The purpose of this study is to validate muscle ultrasound (US) by a gold standard (muscle CT scan) for the assessment of quadriceps muscle thickness in critically ill patients with AKI.
Quadriceps rectus femoris thickness and quadriceps vastus intermedius thickness of critically ill patients with AKI were blindly assessed at the same leg sites by both US and computed tomography (CT) scan. Using bivariate mixed-model linear regression analysis, we estimated, average difference in thickness between measurement sites, agreement (differential and proportional bias) of US compared to CT, and precision of the two methods, and eventually performed Bland-Altman analysis for repeated measurements on pooled results.
We analyzed 233 couples of measurements (30 patients). Average muscle thickness ranged between 1.0 and 1.6, depending on the measurement site. When comparing US to CT, both the observed differential bias (between + 0.04 and + 0.26 cm depending on the muscle site) and the proportional bias (between 82 and 98% of the reference values, depending on the muscle site) were not statistically significant. However, precision analysis showed that US scan tended to be slightly less precise in comparison to CT. Bland-Altman analysis on pooled results showed that the 95% limits of agreement between the US and CT were narrow, ranging from - 0.34 to + 0.36 cm.
In critically ill patients with AKI, quadriceps muscle thickness assessment based on US is unbiased, although it occurs with a minor loss of precision compared to CT.
在危重症患者中，肌肉消耗加速仍然是一个主要问题。然而，重症监护病房的一个关键问题是缺乏床边评估肌肉量的适当工具。此外，当急性肾损伤（AKI）共存时，由于经常发生的肾脏替代治疗导致的液体超负荷和/或快速液体转移，可能会干扰肌肉量评估。本研究的目的是通过金标准（肌肉 CT 扫描）验证肌肉超声（US）在评估伴有 AKI 的危重症患者股四头肌厚度中的作用。
通过 US 和计算机断层扫描（CT）盲法评估 AKI 危重症患者同一腿部的股直肌厚度和股外侧肌中间厚度。使用双变量混合模型线性回归分析，我们估计了测量部位之间的平均厚度差异、US 与 CT 的一致性（差异和比例偏差）以及两种方法的精密度，并最终对汇总结果进行了重复测量的 Bland-Altman 分析。
我们分析了 233 对测量值（30 名患者）。平均肌肉厚度在 1.0 到 1.6 之间，取决于测量部位。当 US 与 CT 比较时，观察到的差异偏差（取决于肌肉部位，在+0.04 到+0.26cm 之间）和比例偏差（取决于肌肉部位，在参考值的 82%到 98%之间）均无统计学意义。然而，精密度分析表明，与 CT 相比，US 扫描的精密度略有下降。对汇总结果的 Bland-Altman 分析表明，US 和 CT 之间的 95%一致性界限较窄，范围在-0.34 到+0.36cm 之间。
在伴有 AKI 的危重症患者中，基于 US 的股四头肌厚度评估无偏差，尽管与 CT 相比，其精密度略有下降。
