Carbon Monoxide-based Rebreathing Method and Bioimpedance to Assess Intra- and Extravascular Volume in Hemodialysis Patients
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 50
- 试验地点
- 2
- 主要终点
- Blood volume by carbon monoxide rebreathing method
研究概览
简要总结
The study is a case-control study with the primary aim of objectifying the volume status of patients receiving hemodialysis. Volume status will be assessed at dry weight and evaluated by a carbon monoxide rebreathing method, that measures blood volume, and bioimpedance that measures total body water. Case-control subjects will be matched on gender, age and weight.
Secondary aims are to evaluate the carbon monoxide rebreathing method. Blood volumes obtained by the carbon monoxide rebreathing method will be correlated to blood volumes obtained by radioactive labelling of erythrocytes and albumin. In addition, it will be investigated whether hemoglobin is a valid marker of anemia in patients receiving hemodialysis by measuring the erythrocyte volume and the hemoglobin mass by the carbon monoxide rebreathing method and correlating this to the hemoglobin concentration measured before and after dialysis.
详细描述
Aim:
- To combine a carbon monoxide rebreathing method and bioimpedance which allows to objectively measure the amount of fluid in the bloodstream (intravascular) and throughout the body, and thereby test the actual amount of fluid in the body when patients are hydrated according to their clinical dry weight.
- To validate carbon monoxide rebreathing method in hemodialysis patients compared against a radioactive labeling of erythrocytes and albumin (the gold standard).
- To investigate whether hemoglobin is a valid marker of anemia in this patient population by measuring the erythrocyte volume and hemoglobin mass by the carbon monoxide rebreathing method and correlating this to the hemoglobin concentration.
Background:
Anemia and overhydration are challenging conditions in patients on hemodialysis. Overhydration is associated with hypertension, cardiomyopathy and increased mortality. In assessing the patient's volume status, blood pressure, body weight and peripheral edema are used as indicators. To achieve a more accurate estimate, these measures have been combined with various techniques, such as relative changes in blood volume (measured with blood volume sensor (BVS)) and bioimpedance. These methods are used to varying degrees in everyday clinical practice.
In case of overhydration, fluid is distributed intravascularly and can thereby expand blood volume. The primary clinical problem with an expanded blood volume is hypertension and increased risk of cardiovascular complications. Measurement of the intravascular volume can therefore have great clinical relevance, but currently there are no direct measures for this implemented in the clinical daily routine. Various techniques have been used for research purposes. These include fluorescent dilution techniques, radioactive labeling of erythrocytes and albumin, as well as infusion of dialysate during dialysis where changes in BVS measurements can be used to calculate the intravascular volumes.
研究设计
- 研究类型
- Observational
- 观察模型
- Case Control
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 90 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- 未提供
排除标准
- 未提供
结局指标
主要结局
Blood volume by carbon monoxide rebreathing method
时间窗: Day 1
Blood volume measured by carbon monoxide rebreathing method in ml/kg
次要结局
- Erythrocyte volume by radioactive labelling of erythrocytes(Day 1)
- Hemoglobin rebound after dialysis(Day 1)
- Erythrocyte volume by carbon monoxide rebreathing method(Day 1)
- Plasma volume by carbon monoxide rebreathing method(Day 1)
- Blood volume by Nadler's formula(Day 1)
- Erythrocyte volume by Nadler's formula(Day 1)
- Plasma volume by Nadler's formula(Day 1)
- Blood volume by radioactive labelling of erythrocytes and albumin(Day 1)
- Plasma volume by radioactive labelling of albumin(Day 1)
- Hemoglobin mass(Day 1)
- time-averaged hemoglobin(Day 1)
- Hemoglobin(Day 1)
- Hemoglobin pre-dialysis(Day 1)
研究者
Bo Feldt-Rasmussen
Professor
Rigshospitalet, Denmark