title: A novel imaging technique to measure capillary-refill time: improving diagnostic accuracy for dehydration in young children with gastroenteritis.
abstract: BACKGROUND
  Assessment of dehydration in young children currently depends on clinical judgment, which is relatively inaccurate. By using digital videography, we developed a way to assess capillary-refill time more objectively.
  
  
  OBJECTIVE
  Our goal was to determine whether digitally measured capillary-refill time assesses the presence of significant dehydration (> or = 5%) in young children with gastroenteritis more accurately than conventional capillary refill and overall clinical assessment.
  
  
  METHODS
  We prospectively enrolled children with gastroenteritis, 1 month to 5 years of age, who were evaluated in a tertiary-care pediatric emergency department and judged by a triage nurse to be at least mildly dehydrated. Before any treatment, we measured the weight and digitally measured capillary-refill time of these children. Pediatric emergency physicians determined capillary-refill time by using conventional methods and degree of dehydration by overall clinical assessment by using a 7-point Likert scale. Postillness weight gain was used to estimate fluid deficit; beginning 48 hours after assessment, children were reweighed every 24 hours until 2 sequential weights differed by no more than 2%. We compared the accuracy of digitally measured capillary-refill time with conventional capillary refill and overall clinical assessment by determining sensitivities, specificities, likelihood ratios, and area under the receiver operator characteristic curves.
  
  
  RESULTS
  A total of 83 patients were enrolled and had complete follow-up; 13 of these patients had significant dehydration (> or = 5% of body weight). The area under the receiver operator characteristic curves for digitally measured capillary-refill time and overall clinical assessment relative to fluid deficit (< 5% vs > or = 5%) were 0.99 and 0.88, respectively. Positive likelihood ratios were 11.7 for digitally measured capillary-refill time, 4.5 for conventional capillary refill, and 4.1 for overall clinical assessment.
  
  
  CONCLUSIONS
  Results of this prospective cohort study suggest that digitally measured capillary-refill time more accurately predicts significant dehydration (> or = 5%) in young children with gastroenteritis than overall clinical assessment.
authors.affiliation: Department of Pediatrics, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Itai
authors.initials: I
authors.lastname: Shavit
authors.forename: Rollin
authors.initials: R
authors.lastname: Brant
authors.forename: Cheri
authors.initials: C
authors.lastname: Nijssen-Jordan
authors.forename: Roger
authors.initials: R
authors.lastname: Galbraith
authors.forename: David W
authors.initials: DW
authors.lastname: Johnson
mesh_terms: D001783:Blood Flow Velocity; D002196:Capillaries / Q000503:physiopathology*; D002675:Child, Preschool; D003681:Dehydration / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology*; D019937:Diagnostic Techniques and Procedures; D005759:Gastroenteritis / Q000139:chemically induced*; D006801:Humans; D007223:Infant; D011446:Prospective Studies; D015203:Reproducibility of Results