Department of Nuclear Medicine, Addenbrooke's Hospital, Cambridge.
Nucl Med Commun. 2021 Jan;42(1):58-62. doi: 10.1097/MNM.0000000000001301.
First, to derive gender-specific formulae for estimation of extracellular fluid volume (eECV) and second, compare eECV as a scaling metric for slope-intercept glomerular filtration rate (GFR) with estimated body surface area (eBSA), lean body mass (eLBM) and total body water (eTBW).
GFR and 'slope-only' GFR (GFR/ECV), both single compartment-corrected, were measured in a previously published multicentre database of healthy potential kidney transplant donors. Measured ECV (mECV) was obtained as ratio GFR-to-GFR/ECV. Formulae for eECV in men and women were derived from the relationship of mECV with height and weight and expressed as eECV = a.weight.height. In a population of prospective kidney transplant donors from a single centre, eECV was compared with mECV. GFR was scaled to eECV, eBSA, eLBM and eTBW, estimated from previously published formulae.
In men and women, respectively, a was 0.0755 and 0.0399, x was 0.6185 and 0.6065 and y was 0.4982 and 0.6217. In the single centre, biases (±precisions) of eECV against mECV in men and women were 0.26 (±1.68) and 0.31 (±1.67) l. Mean GFR/eBSA was higher in men but mean GFR/eLBM and GFR/eTBW were higher in women. Mean GFR/ECV and mean GFR/eECV were very similar between the two genders. GFR/ECV and GFR/eECV showed correlations with each other that were almost identical between men and women.
New formulae are described for estimating eECV. Scaling GFR to eECV is more physiological than scaling to eBSA and accounts for gender. eECV used for measuring GFR from a single blood sample should be gender-specific.
首先，推导出用于估计细胞外液量（eECV）的性别特异性公式；其次，比较 eECV 作为斜率截距肾小球滤过率（GFR）的缩放指标与估计的体表面积（eBSA）、瘦体重（eLBM）和总水量（eTBW）的效果。
在之前发表的一个多中心健康潜在肾移植供体数据库中，测量了单室校正后的 GFR 和“斜率-only”GFR（GFR/ECV）。通过将 GFR 与 GFR/ECV 的比值获得实测细胞外液量（mECV）。从 mECV 与身高和体重的关系中推导出男性和女性的 eECV 公式，并表示为 eECV=a.weight.height。在来自单一中心的前瞻性肾移植供体人群中，将 eECV 与 mECV 进行比较。根据之前发表的公式，将 GFR 缩放至 eECV、eBSA、eLBM 和 eTBW。
男性和女性的 a 值分别为 0.0755 和 0.0399，x 值分别为 0.6185 和 0.6065，y 值分别为 0.4982 和 0.6217。在单一中心，男性和女性 eECV 与 mECV 的偏差（±精度）分别为 0.26（±1.68）和 0.31（±1.67）l。男性的平均 GFR/eBSA 较高，但女性的平均 GFR/eLBM 和 GFR/eTBW 较高。两种性别之间的平均 GFR/ECV 和平均 GFR/eECV 非常相似。GFR/ECV 和 GFR/eECV 之间存在相关性，男性和女性之间几乎相同。
描述了用于估计 eECV 的新公式。将 GFR 缩放至 eECV 比缩放至 eBSA 更具生理意义，并考虑了性别因素。用于从单个血样测量 GFR 的 eECV 应该是性别特异性的。
