MADISON, WIS. – Cyclic parenteral nutrition may be a viable option in very low birth weight infants requiring parenteral nutrition for several weeks, results of a prospective, randomized trial suggest.
Among 114 neonates weighing no more than 1,500 g, the incidence of cholestasis was nearly double at 24% with continuous parenteral nutrition versus 12.5% with cyclic parenteral nutrition.
Although this did not reach statistical significance at a P value of 0.109, there was a downward trend in direct bilirubin beginning in week 7 favoring cyclic parenteral nutrition that was statistically significant by week 8 (1.4 mg/dL vs. 3.2 mg/dL, P = .042), Dr. Maliha Shareef and her colleagues reported at the annual meeting of the Midwest Society for Pediatric Research.
"While feeding advancement regimens may vary in NICUs, this study indicates cyclic parenteral nutrition as an important option when parenteral nutrition is required for extended periods of time," the authors concluded.
Parenteral nutrition-associated cholestasis can develop in up to 35% of premature infants by 1 month of age and be as high as 67% by 3 months of age. The mortality rate is 3%-14% overall, and even higher in infants with short bowel syndrome.
Cyclic parenteral nutrition (PN) has been shown to be effective in reducing cholestasis in children and adults, but minimal data exist on its use and effects in very low birth weight (VLBW) infants, due primarily to concerns for the risk of hypoglycemia.
Theoretically, cyclic PN is thought to prevent PN-induced fatty infiltration of the liver, decrease hyperinsulinemia seen with continuous infusion of dextrose, prevent lipogenesis, and possibly reduce the respiratory quotient, noted Dr. Shareef, an associate professor of pediatrics and neonatology at Loyola University Chicago, Maywood, Ill.
The researchers enrolled 114 infants weighing no more than 1,500 g at birth, who were hemodynamically and metabolically stable and needed PN for more than 1 week. Their median gestational age was 28 weeks. Median birth weight was 1,000 g in the continuous group and 1,050 g in the cyclic group.
All infants were started on continuous total PN and then were evenly randomized beginning on day 7 to continuous PN or 20 hours of total PN and 4 hours of D10 intravenous solution with sodium, potassium, and calcium to provide the glucose infusion rate (GIR) that is within 30% of GIR in total PN. Serum glucose was checked the first 3 days at 30 and 60 minutes off total PN and 30 minutes before restarting total PN. Weekly liver and basic metabolic panels were also obtained.
Hypoglycemia, defined as a serum glucose level less than 40 mg/dL, did not occur in the cyclic group, Dr. Shareef reported in a poster.
Gastrointestinal complications were observed in eight infants in the continuous PN group and seven in the cyclic group, and gram-negative rod infections in six and eight infants, respectively.
The average number of days on total PN was 31.5 in the continuous group and 29 in the cyclic group.
"Cyclic total PN is tolerated in lower birth weight neonates when glucose infusion rate is supported during off hours," the authors wrote. "Further study is needed to determine when cyclic PN should be initiated."
Dr. Shareef and her associates reported no relevant financial disclosures.