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 (≥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 (≥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 ≥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 (≥5%) in young children with gastroenteritis than overall clinical assessment.