Recommendation ID

What is the optimal timeframe for starting parenteral nutrition in term babies who are critically ill or require surgery?

Any explanatory notes
(if applicable)

Why the committee made the recommendations
Indications for starting neonatal parenteral nutrition (recommendations 1.1.1 to 1.1.3)
There was no evidence on the indications for neonatal parenteral nutrition, and limited evidence about the timeframe in which it should be provided, so the committee used their knowledge and experience to make the recommendations.

The committee agreed that all preterm babies born before 31+0 weeks should receive parenteral nutrition from birth until they transition to enteral feeds. Even though there was no specific evidence for this, the committee agreed that there is a risk of significant deficits in nutrition and short-term and long-term adverse events if babies born before 31+0 weeks are not supported by parenteral nutrition from birth.

For preterm babies born at or after 31+0 weeks, it needs to be established whether sufficient progress is made with enteral feeding within the first 72 hours after the birth. The committee decided not to be prescriptive about 'sufficient', to reflect the clinical judgements that healthcare professionals would make depending on each baby's individual circumstances and condition, and because enteral nutrition was not reviewed as part of this guideline. If babies have difficulties tolerating enteral feeds during this time, parenteral nutrition should be provided without delay. The committee was aware of evidence that this group of moderately preterm babies is at increased risk of long-term neurodevelopmental problems, and that optimal early nutrition may reduce the risk.

The committee discussed the influence of gestational age and birthweight on gut maturity and the baby's ability to tolerate enteral feeds. Although weight is closely linked to age, the committee had concerns that including more than 1 parameter may lead to uncertainty in deciding when to start parenteral nutrition, so they based the recommendations solely on gestational age at birth.

Critically ill term babies (with, for example, sepsis), and babies with congenital disorders, may be unlikely to make progress on enteral feeding. The committee agreed that this would be a clinical judgement, depending on each baby's circumstances and condition. They agreed that a delay could have long-term consequences and recommended parenteral feeding for these babies.

Indications for starting neonatal parenteral nutrition if enteral feeds are stopped (recommendations 1.1.4 and 1.1.5)
The committee agreed the timings based on their knowledge and experience, and because preterm babies have limited stores and the potential for accumulating deficits. For term babies, the committee based the recommendation on current practice and their knowledge of the more replete nutritional stores of a baby born at term.

Timing of starting parenteral nutrition (recommendation 1.1.6)
There was evidence to show that, for preterm babies, there are some benefits to starting parenteral nutrition early. However, the definition of 'early' varied in the evidence (ranging from 2 hours to 36 hours without very clear descriptions of the enteral feeding regimen), and there was no consistent pattern of findings. There was evidence for critically ill term babies that compared starting parenteral nutrition early (within 24 hours) with starting it after 1 week. There were some benefits in delaying parenteral nutrition but the committee had reservations about the evidence because the study was relatively small, the parenteral nutrition regimens used were not consistent across the different study sites and the intervention may not have been appropriate because parenteral nutrition would not normally be started on day 1 for critically ill term babies due to restricted fluid volumes and strain on organ systems. The timeframe for starting parenteral nutrition is therefore based on what the committee believe is achievable and safe.

The committee agreed that starting parenteral nutrition within 8 hours of the decision being made to provide it would reduce the risks of a nutritional deficit developing for the smallest babies (born at less than 31+0 weeks). In addition, the committee noted that this timeframe would allow for placement of central lines if needed.

The committee also discussed the timeframe for critically ill babies, but there was not enough evidence to make a separate recommendation. From their knowledge and experience, they were aware that without parenteral nutrition, preterm babies will develop a nutritional deficit more rapidly than term babies who have greater nutritional reserves; therefore, they agreed that it may take longer to decide whether parenteral nutrition in term babies is needed.

However, once the decision is made that parenteral nutrition is needed, it should be started within 8 hours, regardless of whether babies are term or preterm.

The committee recognised the need for further research to inform the timing of starting parenteral nutrition for term babies who are critically ill or require surgery.

How the recommendations might affect practice
The committee agreed that the recommendations would improve consistency of care across neonatal units, and ensure that the nutritional needs of vulnerable babies are met. Hospitals providing care for babies for whom parenteral nutrition is indicated would have to provide access to parenteral nutrition. If a hospital does not have access to neonatal parenteral nutrition, babies would need to be transferred to a unit that could provide it.

Early provision may be more costly because parenteral nutrition and staff would need to be available out-of-hours (including during weekends) to administer parenteral nutrition within the first 8 hours. However, costs can be reduced by using standardised parenteral nutrition bags, as recommended in the section on standardised neonatal parenteral nutrition formulations ('standardised bags'), which can be stored and be readily accessible. The committee believe that there should be no reason why neonatal units cannot stock standardised bags because they have a long enough shelf life to enable storage, as long as a system of stock rotation is in place. The committee also agreed that the costs of early administration would be offset by the positive impact of early optimal nutrition.

Full details of the evidence and the committee's discussion are in:

evidence review A1: predictors of enteral feeding success

evidence review A2: optimal timeframe to start parenteral nutrition.

Source guidance details

Comes from guidance
Neonatal parenteral nutrition
Date issued
February 2020

Other details

Is this a recommendation for the use of a technology only in the context of research? No  
Is it a recommendation that suggests collection of data or the establishment of a register?   No  
Last Reviewed 29/02/2020