The infant, despite whether healthy term or high-risk, will require energy for BMR, thermic effect of food, physical activity, maintenance, growth and for energy lost in feces and urine. There is also energy needed just to maintain body temperature until the early extrauterine period passes. The newborn requires approximately 108 kcal/kg for about six months followed by 98 kcal/kg for the next six.
The high-risk newborn will have the same energy requirements, but Calorie needs will differ in whether or not the infant is enterally fed or parenterally fed. The enterally fed infant needs a greater amount of Calories, at 120/kg, than the healthy infant due to specific dynamic action and cold stress. The parentally fed will need fewer amount of Calories, at about 80-90 kcal/kg, than the healthy infant because of the infant won't use as many calories for activity, cold stress, specific dynamic action or stool losses. Caloric needs for both enterally and parenterally fed high-risk infants will aslo need to depend on medical problems and growth needs.
Assessment methods by which energy needs are determined include anthropometry, biochemical assessment and dietary assessment. Anthropometry assesses weight, length and head circumference. Because weight is most important for the high-risk infant, it will need to be weighed one or more times daily. Biochemcial lab measurements will need to be performed over several days in the high-risk infant to determine development.
The high-risk infant will also need a clinical assessment and a nutrient intake assessment. The clincal assessment will evaluate condition including state of hydration relative to urine and weight gain as well as feeding tolerance including vomiting records. Nutrient intake will evaluate nutrient sources in a qualitative fashion as well as nutrients in terms of quantity. Nutrient sources will need to depend on the condition of the high-risk infant such as state of digestive abilities. Nutrient amounts depends on absorption capacities, whether parenterally or enterally fed and weight.
Mitchell MK. Nutrition Across the Life Span. Second Edition. Waveland Press: Long Grove, Illinois, 2003.