title: The baseline diameter of the inferior vena cava measured by sonography increases with age in normovolemic children.
abstract: OBJECTIVE
  To evaluate normative sonographic measurements of the inferior vena cava (IVC) diameter in healthy pediatric patients.
  
  
  METHODS
  We performed a prospective observational study of a convenience sample of healthy patients between the ages of 0 and 22 years presenting to a pediatric emergency department. Exclusion criteria included abnormal vital signs, pregnancy, or illnesses thought to influence volume status. During quiet respiration, the maximum and minimum IVC diameters were measured in the sagittal plane distal to the hepatic vein-IVC junction. As second measurements, the maximum diameters of the IVC and aorta were measured in the transverse plane distal to the insertion of the left renal vein into the IVC.
  
  
  RESULTS
  From February 2013 through April 2014, 63 children (51% female; mean age, 11 years) were enrolled. There were 20 children in each age group of 2 to 7, 7 to 12, and 12 to 22 years. The correlations between IVC and aortic diameters as a function of age were calculated using the Spearman rank correlation coefficient. The correlation coefficients were all statistically significant (P < .001): sagittal maximum IVC diameter (0.81), sagittal minimum IVC diameter (0.79), transverse maximum IVC diameter (0.79), and transverse maximum aortic diameter (0.81).
  
  
  CONCLUSIONS
  This pilot study of sonographic measurements of the IVC diameter in normovolemic children suggests a statistically significant positive correlation between age and IVC diameter. Future studies should focus on multicenter enrollment, children in the youngest age group, and the development of normative growth curves for the IVC by age, sex, and body mass index.
authors.affiliation: Department of Emergency Medicine, Mount Sinai St Luke's-Roosevelt Hospital Center, New York, New York USA (N.K., T.S., R.E.L.); and Division of Pediatric Emergency Medicine, Columbia University Medical Center, New York, New York USA (L.N.).
authors.forename: Neil
authors.initials: N
authors.lastname: Kathuria
authors.affiliation: Department of Emergency Medicine, Mount Sinai St Luke's-Roosevelt Hospital Center, New York, New York USA (N.K., T.S., R.E.L.); and Division of Pediatric Emergency Medicine, Columbia University Medical Center, New York, New York USA (L.N.).
authors.forename: Lorraine
authors.initials: L
authors.lastname: Ng
authors.affiliation: Department of Emergency Medicine, Mount Sinai St Luke's-Roosevelt Hospital Center, New York, New York USA (N.K., T.S., R.E.L.); and Division of Pediatric Emergency Medicine, Columbia University Medical Center, New York, New York USA (L.N.).
authors.forename: Turandot
authors.initials: T
authors.lastname: Saul
authors.affiliation: Department of Emergency Medicine, Mount Sinai St Luke's-Roosevelt Hospital Center, New York, New York USA (N.K., T.S., R.E.L.); and Division of Pediatric Emergency Medicine, Columbia University Medical Center, New York, New York USA (L.N.).
authors.forename: Resa E
authors.initials: RE
authors.lastname: Lewiss
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001810:Blood Volume; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009929:Organ Size; D010865:Pilot Projects; D011446:Prospective Studies; D012016:Reference Values; D014463:Ultrasonography; D014682:Vena Cava, Inferior / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000254:growth & development; D055815:Young Adult
keywords: inferior vena cava; pediatric ultrasound; pediatrics; point-of-care ultrasound