Chapter 3
Enteral Nutrition
Tracey Johnson
Introduction
Enteral nutrition is the method of supplying nutrients to the gastrointestinal tract. Although enteral nutrition is the term often used to describe nasogastric, gastrostomy and jejunostomy feeding it also includes food and drink taken orally.
Enteral feeding is the preferred method of providing nutrition support to children who have a functioning gastrointestinal tract, with parenteral nutrition reserved for children with severely compromised gut function. It is safer and easier to administer than parenteral nutrition both in hospital and at home and can be adapted to meet the individual requirements of infants and children of all ages.
Some children receive their full nutritional requirements via a nasogastric, gastrostomy or jejunostomy tube, whereas others require nutrition support to supplement poor oral intake or to meet increased nutritional requirements. Enteral feeding may be short term but for many children it can be a long term or even life-long method of feeding. As a result regimens need to be adaptable to ensure each child receives the essential nutrients they require for normal growth and development.
Tube feeding children requires the expert input of a paediatric dietitian who, along with a specialist multidisciplinary team, has the knowledge to use feeds and feeding equipment appropriate for the individual requirements and clinical condition of the patient. Indications for enteral feeding are given in Table 3.1.
Table 3.1 Indications for enteral feeding
| Indication | Example |
| Inability to suck or swallow | Neurological handicap and degenerative disorders |
| Severe developmental delay | |
| Trauma | |
| Critically ill child requiring ventilation | |
| Anorexia associated with chronic illness | Cystic fibrosis |
| Malignancy | |
| Inflammatory bowel disease | |
| Liver disease | |
| Chronic kidney disease | |
| Congenital heart disease | |
| Inherited metabolic disorders | |
| Increased requirements | Cystic fibrosis |
| Congenital heart disease | |
| Malabsorption syndromes (e.g. short gut syndrome, liver disease) | |
| Trauma | |
| Severe burns | |
| Congenital anomalies | Tracheo-oesophageal fistula |
| Oesophageal atresia | |
| Orofacial malformations | |
| Primary disease management | Crohn’s disease |
| Severe gastro-oesophageal reflux | |
| Short bowel syndrome | |
| Glycogen storage disease | |
| Very long chain fatty acid disorders | |
| Refusal to eat | Anorexia nervosa |
| Feeding aversion |
Choice of feeds
The choice of feed is dependent on a number of factors:
- age of child
- gut function
- dietary restrictions and specific nutrient requirements
- route of administration
- prescribability and cost
Infants under 12 months
Many infants requiring tube feeding may be given the same feed they would otherwise be taking orally. Children who are breast fed may be able to continue breast milk and there are physiological and psychological advantages to this. Mother’s expressed breast milk (EBM) may be given to her own baby or pasteurised donor breast milk may be available. The principal benefits of using breast milk are the presence of immunoglobulins, antimicrobial factors and lipase activity. In addition, there is a psychological benefit to the mother if she is able to contribute to the care of her sick child by providing breast milk. These benefits may be outweighed by the possible poorer energy density of EBM, particularly if the fore milk is used which is lower in fat than the hind milk. If the infant fails to gain weight on breast milk alone it can be supplemented with a commercial human milk fortifier (p. 92), or with standard infant formula powder (Table 1.18).
Whether to pasteurise a mother’s EBM when it is to be given to her own baby remains a controversial issue. Pasteurisation will destroy some of its nutritional, antimicrobial, probiotic, hormonal and enzymic properties [1–3] but may protect against pathogenic bacterial contamination. Currently there are no national guidelines for pasteurisation of mother’s EBM to be fed to her own baby and individual hospitals and units have developed their own local protocols. The evidence for the transmission of infection via EBM is limited and the role of pasteurisation unclear. This will largely be influenced by the cleanliness of the collection and handling techniques.
Standard infant formulas are suitable for enteral feeding from birth to 12 months of age for those children with normal gut function and normal nutritional requirements. They provide an energy density of 65–70 kcal (270–290 kJ)/100 mL and meet the European Community Infant Formula Regulations [4]. Follow-on milks may also be used after 6 months of age if their higher protein and iron content is thought to be more beneficial to the child. Many infants requiring enteral feeding will have increased nutritional requirements. Nutrient dense infant formulas such as SMA High Energy, Infatrini and Similac High Energy are commercially available and have been shown to promote better growth than standard formulas with added energy supplements (glucose polymer powders and fat emulsions) [5]. Concentrating standard infant formulas achieves a feed that is more nutrient dense and retains an appropriate protein:energy ratio similar to the commercial nutrient dense formulas (p. 17).
Standard infant formulas are based on cow’s milk protein, lactose and long chain fat. Infants with impaired gut function who do not tolerate whole protein feeds frequently benefit from the use of hydrolysed protein or amino acid based feeds. Such feeds are hypoallergenic and are free of cow’s milk protein and lactose. Many of these formulas also have a proportion of the fat content as medium chain triglycerides which can be beneficial where there is fat malabsorption, e.g. liver disease, short gut syndrome (Table 7.6).
If the specific requirements of an infant cannot be met by a commercial infant formula it is possible to formulate a feed from separate ingredients. These modular feeds allow a choice of protein, fat and carbohydrate and give the flexibility to meet the needs of individual patients. However, they are expensive and time consuming to prepare and there is a greater risk of bacterial contamination and mistakes being made during their preparation. It will take several days to establish a child on a full strength modular feed (Table 7.24). Consequently, modular feeds should only be used if a complete feed is unsuitable and, in the hospital setting, should ideally be prepared in a dedicated special feed preparation area (p. 26).
Children aged 1–12 years (8–45 kg body weight)
Specialist paediatric feeds are available for children 1–12 years of age or who weigh 8–45 kg. Department of Health guidelines [6] indicate that children have differing nutritional requirements according to their age and consequently specifically designed feeds for these age groups are recommended to ensure provision of appropriate levels of protein, micronutrients and electrolytes to optimise growth. Although nutritional profiles of paediatric feeds are designed to meet the specific requirements of children it is still important to assess requirements and intakes for the individual.
Feeds are available for children within three age bands:
- 1–6 years
- 1–10 years
- 7–12 years
All feeds are categorised as Dietary Foods for Special Medical Purposes and must comply with the 1999 EC Directive [7]. Standard paediatric feeds are based on cow’s milk protein but are lactose free and provide three levels of energy density: 100 kcal (420 kJ)/100 mL, 120 kcal (500 kJ)/100 mL and 150 kcal (630 kJ)/100 mL. A lower energy feed, 75 kcal (315 kJ)/100 mL, is also available.
Most product ranges are formulated either with or without added fibre. Those with fibre contain a mix of soluble and insoluble fibre. Constipation is common in exclusively tube fed children, particularly those with neurological impairment [8]. A normal diet contains fibre and with an improved knowledge of the role of dietary fibre it is now common practice for children to receive a fibre containing feed as the standard. Studies have shown that the use of fibre enriched feeds reduces the incidence of constipation and laxative use [9, 10].
Children with neurological impairment form the largest single diagnostic group who have long term enteral feeding at home [11]. This group of children frequently has low energy expenditure and, if a standard feed is provided in the necessary volume to meet recommendations for protein and micronutrients, they may show excessive weight gain. The nutritional needs of this group of children are discussed in Chapter 29, p. 778.
The range of paediatric enteral feeds is outlined in Table 3.2.
Table 3.2 Paediatric enteral feeds
| per 100 mL | ||||
| Age/Weight | Energy kcal (kJ) | Protein g | Fibre g | |
| Nutrini Low Energy Multifibre (Nutricia) | 1–6 years (8–20 kg) | 75 (315) | 2.1 | 0.8 |
| Nutrini (Nutricia) | 1–6 years (8–20 kg) | 100 (420) | 2.8 | — |
| Nutrini Multifibre (Nutricia) | 1–6 years (8–20 kg) | 100 (420) | 2.8 | 0.8 |
| Paediasure (Abbott) | 1–10 years (8–30 kg) | 101 (422) | 2.8 | — |
| Paediasure Fibre (Abbott) | 1–10 years (8–30 kg) | 101 (422) | 2.9 | 0.73 |
| Frebini Original (Fresenius) | 1–10 years (8–30 kg) | 100 (420) | 2.5 | — |
| Frebini Original Fibre (Fresenius) | 1–10 years (8–30 kg) | 100 (420) | 2.5 | 0.75 |
| Clinutren Junior Powder (Nestle) | 1–6 years (8–30 kg) | 100 (420) | 2.97 | — |
| 150 (630) | 4.46 | — | ||
| Frebini Original (Fresenius) | 1–10 years (8–30 kg) | 100 (420) | 2.5 | — |
| Nutrini Multifibre (Nutricia) | 1–6 years (8–20 kg) | 100 (420) | 2.7 | 0.75 |
| Paediasure Fibre (Abbott) | 1–10 years (8–30 kg) | 101 (422) | 2.9 | 0.5 |
| Isosource Junior (Novartis) | 1–6 years (8–20 kg) | 122 (510) | 2.7 | — |
| Nutrini Energy (Nutricia) | 1–6 years (8–20 kg) | 150 (630) | 4.1 | — |
| Nutrini Energy Multifibre (Nutricia) | 1–6 years (8–20 kg) | 150 (630) | 4.1 | 0.8 |
| Paediasure Plus (Abbott) | 1–10 years (8–30 kg) | 150 (630) | 4.2 | — |
| Paediasure Plus Fibre (Abbott) | 1–10 years (8–30 kg) | 151 (632) | 4.2 | 1.1 |
| Frebini Energy (Fresenius) | 1–10 years (8–30 kg) | 150 (630) | 3.75 | — |
| Frebini Energy Fibre (Fresenius) | 1–10 years (8–30 kg) | 150 (630) | 3.75 | 1.13 |
| Tentrini (Nutricia) | 7–12 years (21–45 kg) | 100 (420) | 3.3 | — |
| Tentrini Multifibre (Nutricia) | 7–12 years (21–45 kg) | 100 (420) | 3.3 | 1.1 |
| Tentrini Energy (Nutricia) | 7–12 years (21–45 kg) | 150 (630) | 4.9 | — |
| Tentrini Energy Multifibre (Nutricia) | 7–12 years (21–45 kg) | 150 (630) | 4.9 | 1.1 |
For children with abnormal gut function, as with infants, feeds based on hydrolysed protein and amino acids are available (Table 7.6) and it is also sometimes necessary to use a modular feed (Table 7.24).
Children over 12 years (>45 kg body weight)
The requirements of children over 12 years of age may still be met by a paediatric feed designed for 7–12 year olds; individual assessment is necessary. Standard adult feeds may also be used and are available with energy densities of 1 kcal (4 kJ)/mL and 1.5 kcal (6 kJ)/mL, with and without fibre. Some adult feeds have a protein content of 6 g/100 mL or more so care should be taken when using such feeds for children, even if they are over 12 years of age, as they may provide an excessively high amount of protein. Intakes of copper, chromium, molybdenum and vitamins E, C, B6 and B12 will also be high. Adult peptide based and elemental feeds can be used for children with impaired gut function and it is also necessary in special circumstances to employ the flexibility of a modular feed.
The choice of feeds suitable for children is given in Table 3.3.
Table 3.3 Choice of feeds for enteral feeding
| Normal gut function | Impaired gut function | |
| Infants | Normal energy requirements | |
| Breast milk or standard infant formula | Hydrolysed protein formula, e.g. Pepti-Junior (Cow & Gate), Nutramigen Lipil 1, 2 | |
| (Mead Johnson) | ||
| Amino acid infant formula, e.g. Neocate LCP (SHS) | ||
| Modular feed | ||
| Infatrini Pepti | ||
| High energy requirements | ||
| Breast milk + BMF/standard infant formula | ||
| Concentrated infant formula | ||
| Nutrient dense infant formula (e.g. Infatrini, SMA High Energy, | ||
| Similac High Energy) | ||
| 1–6 years (8–20/30 kg) | Normal energy requirements | |
| Standard paediatric enteral feed, e.g. Nutrini (Nutricia), Paedisure (Abbott) | Hydrolysed protein formula, e.g. Nutrini Peptisorb (Nutricia), Pepdite 1+ (SHS), | |
| Peptamen Junior (Nestle) | ||
| ± fibre | ||
| Amino acid formula, e.g. Neocate Advance (SHS) | ||
| Modular feed | ||
| Peptamen Junior Advance (Nestle) | ||
| High energy requirements | ||
| High energy paediatric enteral feed, |
