当前位置： SCI文献检索 > NUCLEAR MEDICINE COMMUNICATIONS期刊下所有文献 > The early plasma concentration of 51Cr-EDTA in patients with cirrhosis and ascites: a comparison of three models.

The early plasma concentration of 51Cr-EDTA in patients with cirrhosis and ascites: a comparison of three models.

Abstract：

OBJECTIVES:The aim of the study was to determine which of three two-parameter fitting functions (exponential, linear-log, and negative-power function of time) most accurately models early chromium-51-EDTA (51Cr-EDTA) plasma concentration data prior to 120 min in patients with cirrhosis and ascites and understand how these fitting functions affect the calculation of the area under the plasma concentration curve (AUC). METHODS:A bolus, antecubital intravenous injection of 2.6 MBq of 51Cr-EDTA was given to 13 patients with cirrhosis and ascites. Up to 16 blood samples were drawn at time points ranging from 5 to 1440 min following injection. The concentration data prior to 120 min were used as reference data. Early time concentration values, estimated by fitting exponential, linear-log, and negative-power functions of time to the time samples at 120, 180, and 240 min, were then compared with reference data. The AUC was calculated for each patient using the exponential, Bröchner-Mortensen-corrected exponential, and linear-log functions, and these values were compared. RESULTS:The withheld, observed plasma concentrations were (a) most accurately estimated by linear-log functions (Wilcoxon P=0.4548), (b) significantly underestimated by exponential functions (Wilcoxon P=0.0002), and (c) significantly overestimated by negative-power functions (Wilcoxon P=0.0034). The relative errors when ranked from best to worst were those for the linear-log (12.0%, 9.0%), exponential (22.9%, 14.2%), and negative-power (31.9%, 48.4%) functions of time, respectively (median, interquartile range). For each patient, the values for AUC calculated by the exponential function differed significantly (range=3.4-15.3%, median=8.3%) from those calculated by the corrected Bröchner-Mortensen exponential, as to a lesser extent did those values calculated using linear-log functions (range=0.4-8.0%, median=3.0%). CONCLUSION:In patients with cirrhosis, linear-log functions were significantly more accurate than exponential or power functions in estimating early time plasma concentrations (<120 min). However, the improved linear-log early time plasma concentration model does not provide as much correction to the total AUC as does the corrected Bröchner-Mortensen exponential method. This is likely because of the large contribution of late time data to the AUC, and future work is suggested to explore the late time fit problem.

journal_name

Nucl Med Commun

journal_title

Nuclear medicine communications

authors

Wanasundara SN,Wesolowski MJ,Puetter RC,Burniston MT,Xirouchakis E,Giamalis IG,Babyn PS,Wesolowski CA

doi

10.1097/MNM.0000000000000255

subject

Has Abstract

pub_date

2015-04-01 00:00:00

pages

392-7

issue

eissn

0143-3636

issn

1473-5628

journal_volume

pub_type

杂志文章

在线工具

The early plasma concentration of 51Cr-EDTA in patients with cirrhosis and ascites: a comparison of three models.