Feasibility and Impact of the Measurement of Extracellular Fluid Volume Simultaneous with GFR by 125I-Iothalamate Export

@article{citeulike:5918353, abstract = {The feasibility, validity, and possible applications of the assessment of extracellular fluid volume (ECFV) simultaneous with glomerular filtration rate (GFR) were assessed in a series of validation studies using the constant infusion method of 125I-iothalamate (IOT). In 48 subjects with a broad range of GFR, distribution volume (Vd) of IOT corresponded well with Vd bromide (16.71 {+/-} 3.0 and 16.73 {+/-} 3.2 l, respectively, not significant), with a strong correlation (r = 0.933, P < 0.01) and without systematic deviations. Reproducibility assessment in 25 healthy male subjects showed coefficients of variation of 8.6\% of duplicate measurement of Vd IOT during strictly standardized (50 mmol Na+/d) sodium intake. An increase in dietary sodium intake (200 mmol Na+/d) induced a corresponding rise in Vd IOT of 1.11 {+/-} 1.5 l (P < 0.01). In 158 healthy prospective kidney donors, the impact of indexing of GFR to ECFV was analyzed. Age, gender, height, and body surface area (BSA) were determinants of GFR. Whereas GFR, GFR/BSA, and GFR/height were gender-dependent, GFR/ECFV was gender-independent and not related to height or BSA. This supports the potential of normalizing GFR by ECFV. Thus, ECFV can be simultaneously assessed with GFR by the constant infusion method using IOT. After appropriate validation, also other GFR tracers could be used for such a simultaneous estimation, providing a valuable resource of data on ECFV in renal studies and, moreover, allowing GFR to be indexed to the body fluid compartment it clears: the ECFV. 10.2215/CJN.05501207}, author = {Visser, Folkert W. and Muntinga, Jaap H. J. and Dierckx, Rudi A. and Navis, Gerjan}, citeulike-article-id = {5918353}, citeulike-linkout-0 = {http://dx.doi.org/10.2215/CJN.05501207}, citeulike-linkout-1 = {http://cjasn.asnjournals.org/content/3/5/1308.abstract}, citeulike-linkout-2 = {http://cjasn.asnjournals.org/content/3/5/1308.full.pdf}, citeulike-linkout-3 = {http://view.ncbi.nlm.nih.gov/pubmed/18650405}, citeulike-linkout-4 = {http://www.hubmed.org/display.cgi?uids=18650405}, day = {1}, doi = {10.2215/CJN.05501207}, journal = {Clin J Am Soc Nephrol}, keywords = {gfr, scaling}, month = {September}, number = {5}, pages = {1308--1315}, posted-at = {2009-10-10 07:06:51}, priority = {2}, title = {Feasibility and Impact of the Measurement of Extracellular Fluid Volume Simultaneous with GFR by 125I-Iothalamate}, url = {http://dx.doi.org/10.2215/CJN.05501207}, volume = {3}, year = {2008} }

TY - JOUR ID - citeulike:5918353 L3 - citeulike-article-id:5918353 N2 - The feasibility, validity, and possible applications of the assessment of extracellular fluid volume (ECFV) simultaneous with glomerular filtration rate (GFR) were assessed in a series of validation studies using the constant infusion method of 125I-iothalamate (IOT). In 48 subjects with a broad range of GFR, distribution volume (Vd) of IOT corresponded well with Vd bromide (16.71 {+/-} 3.0 and 16.73 {+/-} 3.2 l, respectively, not significant), with a strong correlation (r = 0.933, P < 0.01) and without systematic deviations. Reproducibility assessment in 25 healthy male subjects showed coefficients of variation of 8.6% of duplicate measurement of Vd IOT during strictly standardized (50 mmol Na+/d) sodium intake. An increase in dietary sodium intake (200 mmol Na+/d) induced a corresponding rise in Vd IOT of 1.11 {+/-} 1.5 l (P < 0.01). In 158 healthy prospective kidney donors, the impact of indexing of GFR to ECFV was analyzed. Age, gender, height, and body surface area (BSA) were determinants of GFR. Whereas GFR, GFR/BSA, and GFR/height were gender-dependent, GFR/ECFV was gender-independent and not related to height or BSA. This supports the potential of normalizing GFR by ECFV. Thus, ECFV can be simultaneously assessed with GFR by the constant infusion method using IOT. After appropriate validation, also other GFR tracers could be used for such a simultaneous estimation, providing a valuable resource of data on ECFV in renal studies and, moreover, allowing GFR to be indexed to the body fluid compartment it clears: the ECFV. 10.2215/CJN.05501207 IS - 5 JF - Clin J Am Soc Nephrol EP - 1315 TI - Feasibility and Impact of the Measurement of Extracellular Fluid Volume Simultaneous with GFR by 125I-Iothalamate VL - 3 SP - 1308 KW - gfr KW - scaling AU - Visser, Folkert AU - Muntinga, Jaap AU - Dierckx, Rudi AU - Navis, Gerjan PY - 2008/09/01/ UR - http://dx.doi.org/10.2215/CJN.05501207 ER -