Department of Health Sciences, Section of Anesthesiology, Intensive Care and Pain Medicine, University of Florence, Florence, Italy.
Department of Anesthesia and Intensive Care, Azienda Ospedaliero Universitaria Careggi, Florence, Italy.
Blood Purif. 2020;49(6):685-691. doi: 10.1159/000507013. Epub 2020 Mar 20.
The current effective delivered dose is a quality indicator for continuous renal replacement therapy. Its periodic assessment might enable physicians to deliver personalised treatments. Yet, its quantification as by extracorporeal urea clearance (Cl) is cumbersome and thus often neglected in routine practice. The aim of this in vitro study is to demonstrate the non-inferior effectiveness of assessing the current effective delivered dose using a simpler, cheaper and faster approach based on measurement of fluoride rather than urea extracorporeal Cl.
We compared urea and fluoride removal in 3 post-dilution continuous veno-venous haemofiltration (CVVH) and 3 continuous veno-venous haemodialysis (CVVHD) in vitro experimental models. Experiments ran for 180 min, using 3 L of human blood, heparin anticoagulation and a machine dose of 30 mL/kg/h. Urea and fluoride were measured in the inflow, outflow and effluent lines to compare sieving coefficients (SC), saturation coefficients (SA) and transmembrane Cls.
In CVVH, the median SC values were 1.06 (1.02-1.07) and 1.02 (1.01-1.04) for fluoride and urea, respectively (discrepancy of 4.3%), while transmembrane convective Cls were 31.28 (30.01-31.31) mL/kg/h and 30.30 (29-31.85) mL/kg/h (discrepancy of 3.13%), respectively. In CVVHD, the median SA values were 1.01 (0.96-1.02) and 1 (0.95-1.01) for fluoride and urea, respectively (discrepancy of 1.6%), while transmembrane dialytic Cls were 30.26 (29.52-31.32) mL/kg/h and 31.16 (30-31.75) mL/kg/h (discrepancy of -2.97%), respectively.
Fluoride transmembrane removal was close to that observed with urea, in terms of SC, SA and transmembrane Cl. Fluoride seems as much accurate as urea in assessing the current effective delivered dose during both CVVH and CVVHD and might therefore be adopted for dose measurement. Besides accuracy, fluoride bedside assessment could present many advantages over urea, particularly in terms of availability, costs, time requirement and rapidity of assessment.
目前的有效传递剂量是连续肾脏替代治疗的质量指标。定期评估可能使医生能够提供个性化的治疗。然而，由于其通过体外尿素清除率（Cl）进行定量比较繁琐，因此在常规实践中经常被忽视。本体外研究旨在证明使用更简单、更便宜和更快的方法来评估当前有效传递剂量的非劣效性，该方法基于氟化物而不是尿素体外 Cl 的测量。
我们比较了 3 例后稀释连续性静脉-静脉血液滤过（CVVH）和 3 例连续性静脉-静脉血液透析（CVVHD）中体外实验模型中的尿素和氟化物的清除率。实验持续 180 分钟，使用 3 升人体血液、肝素抗凝和机器剂量 30 毫升/公斤/小时。在流入、流出和流出线中测量尿素和氟化物，以比较筛系数（SC）、饱和系数（SA）和跨膜 Cl。
在 CVVH 中，氟化物和尿素的中位 SC 值分别为 1.06（1.02-1.07）和 1.02（1.01-1.04）（差异为 4.3%），而跨膜对流 Cl 值分别为 31.28（30.01-31.31）和 30.30（29-31.85）毫升/公斤/小时（差异为 3.13%）。在 CVVHD 中，氟化物和尿素的中位 SA 值分别为 1.01（0.96-1.02）和 1（0.95-1.01）（差异为 1.6%），而跨膜透析 Cl 值分别为 30.26（29.52-31.32）和 31.16（30-31.75）毫升/公斤/小时（差异为-2.97%）。
氟化物的跨膜清除率与 SC、SA 和跨膜 Cl 观察到的尿素清除率相近。氟化物在评估 CVVH 和 CVVHD 期间的当前有效传递剂量方面与尿素一样准确，因此可用于剂量测量。除了准确性之外，氟化物床边评估在可用性、成本、时间要求和评估速度方面可能比尿素具有许多优势。
