title: [Measurement of the inferior vena cava diameter for estimating fluid status in hemodialysis patients].
abstract: OBJECTIVE
  To investigate the clinical application of inferior vena cava diameter (VCD) for estimating fluid status.
  
  
  METHODS
  VCD were measured during the expiratory phase (VCD-E) in 64 patients before hemodialysis (hypervolemia) and 71 normovolemia cases by ultrasonography, meanwhile collapsibility index (CI) were calculated.
  
  
  RESULTS
  (1) VCD-E was (10.69 +/- 2.18) mm, CI was (26.24 +/- 6.34)% in normovolemic group; and (13.78 +/- 2.95) mm, (19.28 +/- 6.24%) in hypervolemic group respectively. There were significant differences in both (P < 0.01). (2) Change of VCD-E between pre- and post-dialysis was related with the amount of ultrafiltration during hemodialysis (r = 0.38, P < 0.01). The ratio was (2.0 +/- 1.2) mm.kg-1. (3) By using VCD-E to estimate hypervolemia, receiver operating characteristic (ROC) curve showed if VCD-E > or = 13.0 mm, the sensitivity was 87.0% and the specificity was 87.5%.
  
  
  CONCLUSIONS
  VCD-E in postdialysis patients would approach (10.7 +/- 2.2) mm, which could be interpreted as being close to the dry weight. Thus VCD appears to be a valuable tool in estimating fluid status.
authors.affiliation: Department of Nephrology, Xiangya Hospital, Hunan Medical University, Changsha 410008.
authors.forename: J P
authors.initials: JP
authors.lastname: Ning
authors.forename: Y
authors.initials: Y
authors.lastname: Xiao
authors.forename: L J
authors.initials: LJ
authors.lastname: Tao
authors.forename: Z H
authors.initials: ZH
authors.lastname: Cao
mesh_terms: D000328:Adult; D000368:Aged; D000886:Anthropometry; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010953:Plasma Volume; D006435:Renal Dialysis; D014463:Ultrasonography; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging*