Natural history of conjugated bilirubin trajectory in neonates following parenteral nutrition cessation.

BACKGROUND: There is little published data regarding the rate of bilirubin clearance in newborns following total parenteral nutrition (TPN) cessation, particularly in the neonatal intensive care unit (NICU) population without intestinal failure.

METHODS: The primary aim of this retrospective chart review was to determine the duration and severity of bilirubin elevation in neonates without intestinal failure. Secondary aims were to determine factors that would influence the duration and severity of this biochemical elevation. The authors conducted a retrospective chart review of all infants receiving TPN for ≥ 21 days and with elevated conjugated bilirubin (CB) ≥3 mg/dL upon TPN cessation in a tertiary care NICU from January 1, 2008 to December 1, 2010. Patients with known causes of liver disease or without laboratory values at least four weeks after PN cessation were excluded. Time to maximum conjugated bilirubin (maxCB) post TPN cessation and normalization were the primary outcomes. Secondary factors including number/timing of sepsis events, ethnicity, and ursodiol use were also evaluated.

RESULTS: Forty three infants met inclusion criteria. The majority of patients had increased CB post TPN cessation ("up" group; 27/43, 63%) with maxCB reached 13 days (SD ± 10.3) after TPN cessation. The majority of the cohort achieved normalization of the bilirubin prior to discharge (28/43, 65%). There was no difference in rate of normalization (p = 0.342) between the "up" group (59%) and the group of patients whose bilirubin trended downward following PN cessation ("down" group, 75%). There were no differences between the two groups with respect to gestational age at birth, birth weight, number of sepsis events, gram negative sepsis events, or intestinal resection. Only 30% of Hispanic patients had increased CB post TPN cessation compared to the majority (71%) of non-Hispanic patients. The maxCB of those that had complete normalization was significantly lower value than the maxCB of those that did not normalize (p = 0.016).

CONCLUSIONS: Nearly two-thirds of infants experience a rise in serum bilirubin following PN cessation that can last for weeks, but cholestasis generally improves with time in the majority of infants.