Significantly dehydrated if has 2 or more of the following (LR+ 6.1, CI:3.8-9.8):
Prolonged capillary refill (>2 sec)
Dry mucous membranes
Absence of tears
Abnormal overall appearance
Sunken fontanelle in an infant
Nausea and vomiting 
Esophageal stenosis/atresia
Fever and rash
Pyloric stenosis
Abdominal pain 
Intestinal stenosis/atresia
Abdominal pain
Duodenal atresia