The evaluation of the degree of dehydration in infants can be based on physical examination findings. Vital sign abnormalities (heart rate and blood pressure) often correlate with the degree of dehydration. If available, comparison of current weight to a recent pre-illness weight may also be useful to gauge the degree of dehydration. Signs of dehydration on physical examination include a sunken fontanelle, dry mucous membranes, reduced skin turgor, and/or delayed capillary refill. The classification of dehydration is separated into 3 general categories based on the percentage of body weight loss: mild (< 5%); moderate (5%-10%); or severe (= 10%). Infants with mild dehydration may be irritable but are alert and may be consoled. They may have a slightly sunken fontanelle and dry mucous membranes. Skin turgor and capillary refill are normal. Infants with moderate dehydration are more irritable and difficult to console. The fontanelle is usually sunken and skin turgor is diminished. Generally, capillary refill is normal to modestly delayed. Infants with severe dehydration are often described as listless or lethargic. In addition to the presence of a sunken fontanelle, dry mucous membranes, and diminished skin turgor, capillary refill is often delayed.4,5 Based on the physical examination, the patient has moderate dehydration. Euvolemia or hypervolemia are incorrect because the physical examination findings are consistent with hypovolemia.
- Moderate dehydration.
4. Shavit I, Brant R, Nijssen-Jordan C, et al. A novel imaging technique to measure capillary-refill time: improving diagnostic accuracy for dehydration in young children with gastroenteritis. Pediatrics 2006;118:2402-8.
5. Tibby SM, Hatherill M, Murdoch IA. Capillary refill and core-peripheral temperature gap as indicators of haemodynamic status in paediatric intensive care patients. Arch Dis Child 1999;80:163-6.
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Seminars in Medical Practice
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