{"title":"Intravascular volumes and the influence on anemia assessed by a carbon monoxide rebreathing method in patients undergoing maintenance hemodialysis","authors":"Vårin Vinje, Tobias Bomholt, Carsten Lundby, Peter Oturai, Marianne Rix, Kristine Lindhard, Mads Hornum","doi":"10.1111/hdi.13118","DOIUrl":null,"url":null,"abstract":"<div>\n \n \n <section>\n \n <h3> Introduction</h3>\n \n <p>Fluid overload is a major challenge in hemodialysis patients and might cause hypervolemia. We speculated that hemodialysis patients reaching dry weight could have undetected hypervolemia and low hemoglobin (Hb) concentration (g/dL) due to hemodilution.</p>\n </section>\n \n <section>\n \n <h3> Methods</h3>\n \n <p>The study included hemodialysis patients (<i>n</i> = 22) and matched healthy controls (<i>n</i> = 22). Blood volume, plasma volume, red blood cell volume, and total Hb mass were determined using a carbon monoxide (CO)-rebreathing method in hemodialysis patients reaching dry weight and controls. Blood volume measurements were also obtained by a dual-isotope labeling technique in a subgroup for validation purposes.</p>\n </section>\n \n <section>\n \n <h3> Findings</h3>\n \n <p>In the hemodialysis group, the median specific blood volume was 89.3 mL/kg (interquartile range [IQR]: 76.7–95.4 mL/kg) and was higher than in the control group (79.9 mL/kg [IQR: 70.4–88.0 mL/kg]; <i>p</i> < 0.037). The median specific plasma volume was 54.7 mL/kg (IQR: 47.1–61.0 mL/kg) and 44.0 mL/kg (IQR: 38.7–49.5 mL/kg) in the hemodialysis and control groups, respectively (<i>p</i> < 0.001). Hb concentration was lower in hemodialysis patients (<i>p</i> < 0.001), whereas no difference in total Hb mass was observed between groups (<i>p</i> = 0.11). A correlation was found between blood volume measured by the CO-rebreathing test and the dual-isotope labeling technique in the control group (<i>r</i> = 0.83, <i>p</i> = 0.015), but not the hemodialysis group (<i>r</i> = 0.25, <i>p</i> = 0.60).</p>\n </section>\n \n <section>\n \n <h3> Discussion</h3>\n \n <p>The hemodialysis group had increased specific blood volume at dry weight due to high plasma volume, suggesting a hypervolemic state. However, correlation was not established against the dual-isotope labeling technique underlining that the precision of the CO-rebreathing test should be further validated. The total Hb mass was similar between hemodialysis patients and controls, unlike Hb concentration, which emphasizes that Hb concentration is an inaccurate marker of anemia among hemodialysis patients.</p>\n </section>\n </div>","PeriodicalId":12815,"journal":{"name":"Hemodialysis International","volume":null,"pages":null},"PeriodicalIF":1.2000,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Hemodialysis International","FirstCategoryId":"3","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/hdi.13118","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"UROLOGY & NEPHROLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Introduction
Fluid overload is a major challenge in hemodialysis patients and might cause hypervolemia. We speculated that hemodialysis patients reaching dry weight could have undetected hypervolemia and low hemoglobin (Hb) concentration (g/dL) due to hemodilution.
Methods
The study included hemodialysis patients (n = 22) and matched healthy controls (n = 22). Blood volume, plasma volume, red blood cell volume, and total Hb mass were determined using a carbon monoxide (CO)-rebreathing method in hemodialysis patients reaching dry weight and controls. Blood volume measurements were also obtained by a dual-isotope labeling technique in a subgroup for validation purposes.
Findings
In the hemodialysis group, the median specific blood volume was 89.3 mL/kg (interquartile range [IQR]: 76.7–95.4 mL/kg) and was higher than in the control group (79.9 mL/kg [IQR: 70.4–88.0 mL/kg]; p < 0.037). The median specific plasma volume was 54.7 mL/kg (IQR: 47.1–61.0 mL/kg) and 44.0 mL/kg (IQR: 38.7–49.5 mL/kg) in the hemodialysis and control groups, respectively (p < 0.001). Hb concentration was lower in hemodialysis patients (p < 0.001), whereas no difference in total Hb mass was observed between groups (p = 0.11). A correlation was found between blood volume measured by the CO-rebreathing test and the dual-isotope labeling technique in the control group (r = 0.83, p = 0.015), but not the hemodialysis group (r = 0.25, p = 0.60).
Discussion
The hemodialysis group had increased specific blood volume at dry weight due to high plasma volume, suggesting a hypervolemic state. However, correlation was not established against the dual-isotope labeling technique underlining that the precision of the CO-rebreathing test should be further validated. The total Hb mass was similar between hemodialysis patients and controls, unlike Hb concentration, which emphasizes that Hb concentration is an inaccurate marker of anemia among hemodialysis patients.
期刊介绍:
Hemodialysis International was originally an annual publication containing the Proceedings of the International Symposium on Hemodialysis held in conjunction with the Annual Dialysis Conference. Since 2003, Hemodialysis International is published quarterly and contains original papers on clinical and experimental topics related to dialysis in addition to the Annual Dialysis Conference supplement. This journal is a must-have for nephrologists, nurses, and technicians worldwide. Quarterly issues of Hemodialysis International are included with your membership to the International Society for Hemodialysis.
The journal contains original articles, review articles, and commentary to keep readers completely updated in the field of hemodialysis. Edited by international and multidisciplinary experts, Hemodialysis International disseminates critical information in the field.