Martus Giedre, Bergling Karin, Simonsen Ole, Goffin Eric, Morelle Johann, Öberg Carl M
Department of Clinical Sciences Lund, Nephrology Division, Skane University Hospital, Lund University, Lund, Sweden.
Division of Nephrology, Cliniques Universitaires Saint-Luc, Brussels, Belgium.
Kidney Int Rep. 2020 Sep 19;5(11):1974-1981. doi: 10.1016/j.ekir.2020.09.003. eCollection 2020 Nov.
The osmotic conductance to glucose (OCG) is a crucial determinant of ultrafiltration (UF) in peritoneal dialysis (PD) patients and can be used to monitor membrane integrity in patients on long-term PD. It has been proposed that OCG can be assessed based on drained volumes in 2 consecutive 1-hour glucose dwells, usually 1.5% and 4.25% glucose, in a so-called double mini-peritoneal equilibration test (dm-PET). However, recent data indicated that the dm-PET provides a poor estimate of OCG unless the residual volume (RV) is taken into account. We introduce an easy, robust, and accurate method to measure OCG and compare it with conventional methods.
In a prospective cohort of 21 PD patients, a modified version of the dm-PET was performed, along with the determination of RV before, between, and after dwells. Based on computer simulations derived from the 3-pore model (TPM) for membrane permeability, we developed and validated a novel single-dwell method to estimate OCG. We next validated the equation in an independent cohort consisting of 32 PD patients.
Single-dwell OCG correlated more closely with actual UF ( = 0.94 vs. r = 0.07 for conventional dm-PET), sodium sieving, and free water transport (FWT) compared with other methods. These findings were replicated in the validation cohort in which OCG calculated using the single-dwell method closely correlated with parameters of osmotic water transport, even when RV was not taken into account, using only drained volumes.
We propose a novel, easy, and robust single-dwell method to determine OCG in individual patients and to monitor membrane integrity over time on PD.
葡萄糖渗透传导率（OCG）是腹膜透析（PD）患者超滤（UF）的关键决定因素，可用于监测长期接受PD治疗患者的膜完整性。有人提出，在所谓的双迷你腹膜平衡试验（dm-PET）中，可以根据连续两个1小时葡萄糖驻留期的引流液量来评估OCG，通常使用1.5%和4.25%的葡萄糖溶液。然而，最近的数据表明，除非考虑残余量（RV），否则dm-PET对OCG的估计效果较差。我们介绍一种简便、可靠且准确的测量OCG的方法，并将其与传统方法进行比较。
在一个由21名PD患者组成的前瞻性队列中，进行了改良版的dm-PET，并在驻留期之前、期间和之后测定RV。基于从膜通透性的三孔模型（TPM）得出的计算机模拟结果，我们开发并验证了一种用于估计OCG的新型单驻留方法。接下来，我们在一个由32名PD患者组成的独立队列中验证了该公式。
与其他方法相比，单驻留OCG与实际超滤（传统dm-PET的r = 0.07，而单驻留OCG的r = 0.94）、钠筛过和自由水转运（FWT）的相关性更强。这些发现也在验证队列中得到了重复，在该队列中，即使不考虑RV，仅使用引流液量，通过单驻留方法计算的OCG与渗透水转运参数密切相关。
我们提出了一种新颖、简便且可靠的单驻留方法，用于测定个体患者的OCG，并在PD治疗过程中随时间监测膜完整性。
