Pediatric Dehydration Score Calculator

The true measure of acute dehydration is the percentage of body weight lost, calculated against a reliable pre-illness weight, but that weight is rarely available when a vomiting toddler arrives in an emergency department. Clinical scoring substitutes for it. The Clinical Dehydration Scale uses four signs, each rated 0, 1 or 2: general appearance, from alert and playful through thirsty or lethargic but irritable when touched to drowsy, limp, cold or sweaty; the eyes, from normal through slightly sunken to grossly sunken; mucous membranes and tongue, from moist through sticky to dry; and tears, from normal through decreased to absent. The four are added for a total of 0 to 8, where 0 corresponds to no dehydration and under about 3 percent weight loss, 1 to 4 to some dehydration at roughly 3 to 6 percent, and 5 to 8 to moderate or severe dehydration at 6 to 9 percent or more. These four were chosen for acceptable inter-observer agreement, unlike skin turgor and capillary refill, which are more sensitive but vary between examiners and with ambient temperature. The score points to a fluid plan rather than a precise deficit. Some dehydration is managed with oral rehydration solution at roughly 50 to 100 mL/kg in small frequent volumes over three to four hours, with reassessment every one to two hours. Poor perfusion or failure of oral therapy calls for an isotonic bolus of 20 mL/kg and replacement of the remaining deficit over 24 to 48 hours alongside maintenance fluid, estimated by the Holliday-Segar rule of 100 mL/kg per day for the first 10 kg, 50 mL/kg for the next 10 kg and 20 mL/kg thereafter. The main caveats are that the scale was derived in children aged roughly one to three years with gastroenteritis and performs less consistently outside that group, that it can mislead in hypernatraemic dehydration where skin and mucosal signs lag, and that malnutrition alters the appearance of all four signs.

The scientific basis for treating this problem at all came from cholera research in South Asia in the 1960s, when work in Dhaka and Calcutta showed that glucose-coupled sodium transport in the small intestine remains intact during secretory diarrhoea, so an oral solution containing both can replace losses without a drip. Dilip Mahalanabis demonstrated the practical consequence in refugee camps on the Indian border with Bangladesh in 1971, where oral rehydration administered largely by family members cut mortality dramatically. The World Health Organization and UNICEF adopted a standard oral rehydration salt formulation soon afterwards and revised it in 2002 to a reduced-osmolarity solution of about 245 mOsm/L, which lowers stool output and vomiting compared with the original. Assessing how dehydrated a child actually is proved harder than treating it. WHO field classifications divided children into no, some and severe dehydration using combinations of signs, and North American work in the 1990s, notably by Marc Gorelick and colleagues in Philadelphia, tested individual physical findings against measured weight change and found most of them only modestly accurate on their own. The four-item Clinical Dehydration Scale was developed from that literature at the Hospital for Sick Children in Toronto, with Jeremy Friedman and colleagues publishing the derivation in The Journal of Pediatrics in 2004 and Ran Goldman and colleagues reporting a prospective validation in a separate emergency department cohort in 2008. The separate maintenance fluid rule it is usually paired with dates from Malcolm Holliday and William Segar in 1957, who tied fluid requirement to energy expenditure rather than body weight alone.