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Parenteral nutrition in premature infants

Richard J Schanler, MD
Section Editor
Steven A Abrams, MD
Deputy Editor
Alison G Hoppin, MD


The nutritional needs of premature infants are usually dependent upon parenteral nutrition (PN) during early postnatal life, especially for very low birth weight (VLBW) infants (birth weight of less than 1500 g). In these infants, full enteral feedings are generally delayed because of the severity of medical problems associated with prematurity, such as immature lung function (which often requires endotracheal intubation and mechanical ventilation), hypothermia, infections, and hypotension. In addition, early enteral feeds are also delayed because of concerns that aggressive feeding may lead to complications, such as feeding intolerance or necrotizing enterocolitis. As a result, the nutritional requirements of VLBW infants are rarely met by enteral feeds in the first two weeks after birth [1]. (See "Short-term complications of the preterm infant".)

PN (sometimes referred to as hyperalimentation) in the premature infant, including its composition, will be reviewed here. The approach to enteral nutrition in premature infants is discussed separately. (See "Approach to enteral nutrition in the premature infant".)


General goals — Because adequate enteral nutrition cannot be established in most very low birth weight (VLBW) infants in their early weeks, PN is initiated to correct in-utero growth restriction and to prevent subsequent growth faltering. More mature, and larger, premature infants may not require PN, because these infants usually tolerate early enteral nutrition. (See "Growth management in preterm infants".)

PN for the premature infant includes the following:

Adequate calories for energy expenditure and growth


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Literature review current through: Jul 2017. | This topic last updated: Jul 20, 2017.
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