Parenteral Nutrition (PN) is administered intravenously, and either peripheral or central venous lines can be used. Central lines are often inserted through the umbilical vessels in new-born infants; however, lines can also be inserted peripherally; they are used for drug infusions as well as PN. Central lines are positioned in a large bore central vein. This allows infusion of more concentrated substances securely; and in general these lines are able to be left in situ for a longer period of time if carefully maintained. However, they require a greater degree of technical skill for insertion; and can be more prone to serious complications such as being a source of late onset sepsis. Peripheral lines are very commonly used for a number of indications on neonatal units and are generally easier to insert. They have a shorter life span. As the infusions are running into a smaller peripheral vein, there is greater risk of the infusion causing direct damage to the vein (thrombophlebitis) or leaking out into the surrounding tissues (extravasation). This is particularly true where there is a higher concentration (as measured by osmolality or osmolarity depending on the unit of measurement) of the PN infusion fluid, such as a formulation with a higher dextrose load. Current practice varies with regards to the administration of PN centrally or peripherally, and this review aims to look at whether the osmolality or osmolarity of PN can help guide whether it is safe to administer peripherally or if PN should be administered centrally.

National Guideline Alliance (UK) (2020) Venous access: Neonatal parenteral nutrition: Evidence review B. National Institute for Health and Care Excellence (UK). London. February 2020. NICE guideline NG154.