Carnitine supplementation of parenterally fed neonates.

Newborn neonates requiring parenteral nutrition (≤28 days old; >50% of calories from PN); included premature infants (27–37 weeks) and some term post-surgical neonates; extremely preterm not included; randomized controlled trials comparing carnitine supplementation vs no supplementation; routes included intravenous or enteral; some studies reported blinding; randomization stratified in a couple of studies.

Carnitine supplementation given parenterally (intravenous) at 50–150 micromol/kg/day; duration varied from about 6 days (Schmidt-Sommerfeld 1983) to 6–21 days (Larsson 1990); two-week supplementation reported in Helms 1995 and Bonner 1995; Shortland 1998 used parenteral supplementation during PN followed by oral supplementation after enteral feeds were established, continuing until about 40 weeks’ gestation.

Carnitine supplementation did not improve weight gain, lipid tolerance, or ketogenesis in neonates on parenteral nutrition. A small, statistically significant but clinically negligible increase in beta-hydroxybutyrate was observed in some analyses. No consistent differences in free fatty acids, triglycerides, or maximum lipid tolerated. Routine carnitine supplementation is not justified based on randomized evidence. Future research should focus on longer-term total PN neonates with robust outcomes such as growth and lipid tolerance.

Small, short-term trials with heterogeneous outcomes; partial or unclear blinding/randomization in several studies; variation in dosing/regimens; some trials excluded due to co-interventions; limited data for long-term outcomes.