A nurse is caring for an infant whose guardian reports intermittent vomiting for several days. Exhibits Which of the following actions should the nurse take? (Select all that apply)

A. Weighing the infant is important to assess for dehydration and failure to thrive, which are common in pyloric stenosis. B. Measuring head circumference is standard for infants to monitor overall growth, though less directly related to pyloric stenosis. C. Offering small, thickened feedings is not appropriate; the infant should be NPO if surgical intervention is anticipated. D. Administering an enema is contraindicated; vomiting and obstruction are due to pyloric stenosis, not constipation. E. Monitoring intake and output is essential to assess hydration status and fluid balance due to ongoing vomiting. F. The FACES pain scale is for children older than 3 years; an infant requires an observational pain scale such as the FLACC scale. G. Contact precautions are not required, as pyloric stenosis is not contagious.