Evidence map›Paper›PMID 42374228›Full record

ArticleBMC nephrology2026

Assessment of correlation between effluent fluid ionized calcium and post-filter ionized calcium in critically ill patients undergoing regional citrate anticoagulation in continuous renal replacement therapy (RCA-CRRT).

Niroj Mali, Saroj Mali, Mingjin Dai, Lingxi Zhang, Fang Wang, Yingying Yang, Xiankun Sun, Hongxia Zou, Ling Zhang, Ping Fu

Abstract read
In one paragraph

Article in BMC nephrology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

10 authors.

Niroj Mali *Department of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
Saroj Mali *School of Information and Software Engineering, University of Electronic Science and Technology of China, Chengdu, 610054, China.
Mingjin DaiDepartment of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
Lingxi ZhangDepartment of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
Fang WangDepartment of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
Yingying YangDepartment of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
Xiankun SunDepartment of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
Hongxia ZouDepartment of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
Ling ZhangDepartment of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China. zhangling_crrt@163.com.
Ping FuDepartment of Nephrology and Institute of Kidney Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China. fupinghx@scu.edu.cn.

Funding

The National Key Research and Development Program of China (2023YFC2411800) 2023YFC2411800The study was supported by the 1.3.5 project for disciplines of excellence from West China Hospital of Sichuan University (ZYGD23015) ZYGD23015
6 · The paper itself

Abstract

backgroundRegional citrate anticoagulation (RCA) is standard in continuous renal replacement therapy (CRRT). Post-Filter ionized calcium (Post-Filter iCa) is the gold standard for monitoring anticoagulation efficacy, but it requires blood sampling. Effluent fluid iCa can be measured without blood sampling. This study assessed the correlation and agreement between Effluent Fluid iCa and Post-Filter iCa in critically ill patients undergoing RCA-CRRT.

methodsWe conducted a prospective non-interventional study from June to November 2024 at West China Hospital of Sichuan University. Thirty-six critically ill patients receiving CVVHDF with RCA were enrolled, yielding 216 paired samples. Ionized calcium was measured in Pre-Filter, Post-Filter, and Effluent Fluid samples using a point-of-care analyzer. CRRT was performed using the Prismaflex system with ST150 filters and Oxiris tubing. Post-filter blood and effluent fluid samples were drawn simultaneously to ensure direct comparability.

resultsThis study analyzed 216 paired samples from 36 critically ill patients on CVVHDF with RCA to assess the relationship between Post-Filter and Effluent Fluid ionized calcium. A moderate correlation was found (r = 0.551 [CI 0.45,0.64], p < 0.001). Bland-Altman analysis showed a mean difference of - 0.024 mmol/L (95% CI: -0.033 to - 0.015), with limits of agreement from - 0.153 (95% CI: -0.1682 to - 0.1378) to 0.105 mmol/L (95% CI: 0.0900 to 0.1204). Variance component analysis demonstrated that only 13.3% of variability (ICC = 0.134) was attributable to between-patient differences, while 86.7% reflected within-patient temporal variation. ICC for Post-Filter iCa reliability over time was 0.269, and for Effluent iCa was 0.146, indicating substantial dynamic changes. Agreement between methods was moderate at early time points (ICC 0.514-0.628 at 2-24 h) but declined at 48-72 h (ICC 0.424-0.435). Cluster analysis of serial calcium measurements identified three distinct profiles among 36 patients: a dominant cluster (66.7%, n = 24) with target-range levels; a high-calcium cluster (19.4%, n = 7), and a low-calcium cluster (13.9%, n = 5).

conclusionEffluent Fluid iCa demonstrates moderate correlation with Post-Filter iCa but substantial within-patient variability limits its use as a direct substitute. While it may offer some supplementary information for tracking anticoagulation trends, it cannot replace Post-Filter sampling at present. Cluster analysis identified distinct calcium phenotypes associated with filter lifespan, though further multicenter validation would be needed to explore potential clinical utility.

Indexed as

AnticoagulantsCalciumCitric AcidContinuous Renal Replacement TherapyCritical IllnessAgedFemaleHumansMaleMiddle AgedProspective StudiesAnticoagulantsCalciumCitric AcidAnticoagulantsCalciumCitric acidContinuous renal replacement therapyEffluent fluidIonized calciumPost-filterPost-filter iCaRegional citrate anticoagulation

Identifiers

PMID42374228
PMCPMC13317417

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.