1. The diagnosis of children should be infantile diarrhea (suspected rotavirus enteritis). As far as the symptoms given above are concerned, there are hyperosmotic dehydration (decreased urine output, no urination for 12 hours, crimson anterior fontanel and eye socket, poor skin elasticity) and metabolic acidosis (confusion, shortness of breath, red lips, Co2cp6544). 2. On the first day, the rehydration plan should be to expand the volume, quickly input 20*5= 100ml of isotonic fluid, and then supplement the accumulated loss, and use a half sodium solution of150 * 5 = 750,750-100 = 650 ml.