A 3 year old girl is brought to the emergency room by EMS after having diarrhea for 5 days and feeling lethargic for the past 12 hours. She has a history of wheezing with viral illnessess. Immunizations are up to date.  Family history reveals that family members are well other than 2 siblings who have had diarrhea. Social history reveals that the patient's parents are separated. Upon examination, the patient appears dehydrated. The patient is responsive but lethargic. The neurological,respiratory, and skin exams appears normal. The cardiovascular examination shows normal heart sounds. Mucous membranes are dry, pulses are palpable but weak, capillary refill is 5 seconds centrally and peripherally. The abdominal examination reveals diffuse but non-peritonitic tenderness.