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Carnitine supplementation of parenterally fed neonates

  • Review
  • Intervention




Carnitine, a quaternary amino acid, plays an important role in the oxidation of long chain fatty acids. Both breast milk and infant formulas contain carnitine. However, it is not routinely provided in parenteral nutrition solutions. Non supplemented parenterally fed infants have very low tissue carnitine levels. The clinical significance of this is uncertain. Carnitine deficiency may be an etiological factor in the limited ability of premature babies to utilize parenteral lipid. In vitro studies have suggested that fatty acid oxidation is impaired when the tissue carnitine levels fall below 10% of normal. Therefore relative carnitine deficiency may impair fatty acid oxidation, thus reducing the available energy and impairing growth.


The primary aim of this review is to determine whether carnitine supplementation of parenterally fed neonates will improve weight gain.
The secondary aims are to determine the effect on lipid tolerance and ketogenesis.

Search methods

Computerised searches were carried out by both reviewers. Searches were made of Medline, Embase, The National Research Register (UK), the Cochrane Controlled Trials Register and expert informants. The MeSH headings used were carnitine and parenteral nutrition.

Selection criteria

Only randomised trials were considered. Trials were included if they involved carnitine supplementation alone, parenterally fed newborn infants, and measured at least one outcome of interest (weight gain, plasma fatty acids, plasma triglycerides, quantity of lipid tolerated, respiratory quotient or beta hydroxybutyrate levels).

Data collection and analysis

The two reviewers searched the literature separately and reached a consensus for inclusion of trials. Data were extracted and evaluated by the two reviewers independently of each other. Authors were contacted if possible to clarify or provide missing data.

Main results

Fourteen studies were identified, six met the selection criteria. The results of the review are limited by the fact that the studies were generally short term and studied different outcomes. One study examined short term and long term weight gain, three reported only short term weight gain, three reported biochemical results in response to a short lipid challenge, and two reported results obtained during normal parenteral nutrition.

Among infants supplemented with carnitine, there was no evidence of effect on weight gain, lipid utilization or ketogenesis.

Authors' conclusions

We found no evidence to support the routine supplementation of parenterally fed neonates with carnitine.








由兩位作者員進行網路數位檢索。檢索的資料庫包括了MEDLINE,EMBASE,The National Research Register (UK), the Cochrane Controlled Trials Register和專家訊息。使用的MeSH題詞是肉鹼(cacrtine)和腸外營養(parenteral nutrition)。


只收納隨機試驗。納入涉及單純補充肉鹼(Carnitine),腸外營養新生兒,以及至少測量一項要關心的結果(體重增加,血漿脂肪酸,血漿三酸甘油酯,脂質耐受量,呼吸商或beta hydroxybutyrate量)的試驗。









此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。



Plain language summary

Carnitine supplementation of parenterally fed neonates

Not enough evidence that carnitine supplements improve weight gain in parenterally fed newborns. Preterm newborns (born before 37 weeks) frequently need extra nutritional supplements parenterally (given other ways than by the mouth). Carnitine is an amino acid found in both breast milk and infant formulas but is not routinely given parenterally. It helps fatty acids to convert into energy and helps in growth. The review of trials found not enough evidence to show any benefit of parenteral carnitine supplements on weight gain or lipid tolerance in preterm newborns. More research is needed.