nutrition for older patients for up to 5 - 7 days, parenteral nutrition should be
started early if it is anticipated that an illness will not allow feeding after 5-7 days.
Infants should immediately be given parenteral nutrition because of the increased
requirements for development and growth. Other indications for parenteral
nutrition include short bowel syndrome, radiation enteritis, intractable vomiting
and diarrhea, severe acute pancreatitis and high output enterocutaneous fistulae.
A. Composition of Parenteral Nutrition
Glucose is an essential fuel source especially for brain metabolism. At
birth, the cord glucose is approximately two thirds that of the maternal blood
glucose and falls to a low point at 1-2 hours of age. Sick infants should be
monitored closely as their glucose levels may fall more rapidly and a glucose
infusion should be initiated earlier. Infants who are preterm or growth restricted
or who have experienced placental insufficiency often have low liver glycogen
stores and may fail to maintain adequate serum glucose levels. Infants of
diabetic mothers are also at risk for hypoglycemia because high levels of
maternal blood glucose cross the placenta causing fetal hyperinsulinemia, which
persists after birth. For any blood glucose less than 40 mg/dL, an infusion of
dextrose should be initiated. Symptomatic hypoglycemia should be treated with
a 2 ml/kg bolus of D10W followed by a continuous glucose infusion. Glucose
levels should then be checked at 30-minute intervals with continued surveillance
until stabilization. Insulin resistance and hyperglycemia may occur in septic
patients or extremely premature infants.