- Email: [email protected]
Managing slow growth in preterm infants fed on human milk
Journal of Neonatal Nursing (2013) 19, 182e188
www.elsevier.com/jneo
Managing slow growth in preterm infants fed on human milk Elizabeth Jones*, Sue Bell, Shiva Shankar Neonatal Intensive Care Unit, University Hospital of North Staffordshire, Newcastle Road, Stoke-on-Trent ST4 6QG, UK Available online 21 May 2013
KEYWORDS Human milk; Expressed breast milk; Protein intake; Breast milk fortifier; Preterm breastfeeding
Abstract The benefits of human milk for the preterm infant are well documented. However, after the first 2e3 weeks following delivery, the nutrient content in human milk may be insufficient to promote growth in the rapidly growing preterm infant. The challenge for the neonatal team is to develop clinical strategies that support the use of human milk and the establishment of breastfeeding, while supporting infant weight gain and growth. A range of clinical strategies are required to monitor growth and manage sub-optimal growth. Over 50% of the energy babies receive from mature breast milk is from lipids. Hence it is very important to minimise fat loss during milk collection, handling and storage while giving expressed breast milk to maximise growth. Once breastfeeding has been established an assessment should be performed to ensure that attachment and positioning is optimal and that feeding care plans are in place, to ensure infant growth does not falter following discharge from hospital. ª 2013 Neonatal Nurses Association. Published by Elsevier Ltd. All rights reserved.
Importance of breast milk The benefits of human milk in preterm infants are well documented (Agostini et al., 2010). Human milk contains immunological factors that potentially reduce the incidence of sepsis and necrotising enterocolitis (Agostini et al., 2010). Strong evidence also suggests that the absorption rate of * Corresponding author. E-mail address: [email protected] (E. Jones).
nutrients from human milk is better than from breast milk substitutes. The enzymes, hormones and growth factors found in human milk play important roles in gastrointestinal growth and maturation and may accelerate the establishment of enteral feeding in infants fed human milk (Meier et al., 2010). The constituents of breast milk have three main functions: To provide nutrition To give immune protection
1355-1841/$ - see front matter ª 2013 Neonatal Nurses Association. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jnn.2013.04.004
Managing slow growth in preterm breastfed infants To promote development Some constituents accomplish all three. Mothers’ own expressed breast milk provides the ideal transition to extra-uterine nutrition. Preterm infants have higher nutrient requirements than term infants, and after the first 2e3 weeks of lactation the protein content of human milk is usually insufficient to meet the
Fig. 1
183 nutritional demands of rapidly growing preterm infants (Weber et al., 2001). The majority of preterm infants born <34 weeks gestation exclusively fed on human milk are at risk of slower rate of weight gain than in utero. This deficit in growth is largely due to the additional protein requirements needed to accelerate preterm growth. If energy is also insufficient then the infant will use protein for energy, which will compound the deficit further. If
UK WHO growth chart.
184
E. Jones et al.
this is uncorrected the deficit in protein and/or energy can effect both growth and neurocognitive development in babies born preterm (Nagaya et al., 2007). Therefore, the priority for neonatal care must be to develop strategies that support both the feeding of human milk while supporting adequate infant growth. Table 1 illustrates that the protein requirements for preterm infants are substantially higher than those for babies born at term (Agostini et al., 2010).
Assessing preterm infant growth In order to assess optimal growth on an individual basis, head circumference, length and weight need to be plotted weekly on a growth chart (Fig. 1 e UK WHO Growth Chart, 2009). This will give a visual tool of overall growth, and it will show which centile the infant is on following the initial diuresis which occurs post-delivery. These centiles can be used for assessing poor weight gain and growth. The growth parameters shown to indicate intrauterine growth should only be used as a guide. The growth chart will enable a more accurate assessment on an individual basis. Table 2 shows the average growth in utero for head circumference, length and weight gain (Agostini et al., 2010). The following factors can contribute to a diagnosis of poor growth: Progressive weight loss or static weight over several days (other than the early postnatal period) When weight velocity alone decreases over 2 weeks (Decreased growth velocity occurs when growth continues but at a lower rate than is needed to follow the centile). Once a diagnosis of poor growth has been established nutritional supplementation is often required, particularly in situations where it is hard to deliver high volumes of breast milk. In the United Kingdom and Ireland, additional nutrients are usually given via a multi-nutrient fortifier. The guidelines in Table 3 are based on a briefing paper of what constitutes current clinical practice in the UK and Ireland (King and Bell, 2010). An array of
Table 1
Table 2
Optimal growth in preterm infants.
The average weight gain for preterm growth is 15e20 g/kg day 30 g a day if >2 kg Length is 0.9 cm per week Head circumference is 0.9 cm per week
nutrients and macronutrients have been added to breast milk fortifiers, in order to maximise infant growth. Table 4 illustrates the range of nutrients that have been included in most commercial breast milk fortifiers used in the UK. It is very important to reassure mothers that breast milk is vitally important to her baby and that she should continue to express her milk. Meier et al. (2010) describe human milk to mothers ‘as a perfect medicine that only a mother can provide’. It can be helpful to explain that preterm babies cannot always take adequate volumes of breast milk and that they have very high demands for protein, minerals and vitamins. Therefore, it is sometimes necessary to supplement babies for a short time simply to help a baby to grow.
Managing sub-optimal growth Since human milk is very variable in composition, the analysis of mothers’ own expressed breast milk is an ideal tool to monitor infant nutrition on an individual basis (Jones et al., 2012). If the protein content is <2.3 g/100 mL volumes should be increased to above 150 mL/kg/day, whenever possible, to avoid fortification. If protein is the limiting nutrient then the addition of a breast milk fortifier can improve growth. If growth remains poor after the addition of a fortifier, a hind milk policy can be used if the mother has a good milk supply. If this fails to promote growth then the addition of preterm formula in conjunction with breast milk can be utilised. High energy formula is also prescribed to promote growth in fluid restricted infants. Caution is needed when using high energy formulas as the nutritional composition is designed specifically for term infants. It is important to remember that not all suboptimal growth and weight gain is attributed to
Protein and energy requirement comparisons (term/preterm).
Daily recommendation Energy (kcal/kg/day) Protein (g/kg/day)
Preterm <1 kg 110e135 3.5e4.5
Preterm e 1e1.8 kg 110e135 3.5e4.0
Term e 0e3 months (DHSS ’91) 115e100 2.1
Managing slow growth in preterm breastfed infants Table 3
Guidelines for the use of breast milk fortifiers.
Criteria for starting fortification All babies <1.5 kg birth weight and <34 weeks Consider babies 1.5e2 kg birth weight and <34 weeks Babies >2 kg birth weight are unlikely to need BMF Plus; Receiving 50 per cent total feeds as breast milk Tolerating feed volumes at a minimum of 150 ml/kg/ day e preferably 180 ml/kg Serum urea < 4 mmol/l and falling What to add Commercially available fortifier following dose according to manufacturer’s instructions How to add Use manufacturers’ instructions Warm for as brief a period as possible and avoid temperatures >37 C Mix well but avoid vigorous shaking Fortify the minimum volume possible, and use before fortifying more Consider starting at half strength for 24 h if baby at risk of poor tolerance Monitoring and additional supplementation Weekly weight, length and head circumference If growth falters calculate nutrient intake and compare with recommended intakes Weekly serum phosphate, calcium, sodium and alkaline phosphatase Weekly serum urea taking into account possible increases with dehydration compromised renal function, sepsis, steroid therapy and inadequate non protein energy intake If urea within normal range but growth is faltering consider use of hind milk Give iron supplement between four to six weeks Criteria for stopping fortification On <50 per cent total feeds EBM and growth satisfactory If growth not satisfactory carry on BMF until <25 per cent total feeds EBM Able to fully demand breast feed At discharge together with satisfactory growth Assess babies individually to see if BMF post discharge
inadequate nutrition. The following indices need to be part of the assessment prior to planning any nutritional intervention:
Sodium depletion Anaemia Steroid treatment Sepsis/trauma Fluid imbalance Reflux
185 In addition, conditions such as patent ductus arteriosus and chronic lung disease can increase nutritional requirements, and cholestasis can cause the malabsorption of nutrients.
Practical methods for preserving human milk lipids (fat) Over 50% of the energy babies receive from human milk is from lipids (fat) (Table 5 e McCance and Widdowson, 2002). By using very practical strategies, neonatal nurses can minimise lipid loss during the processes of milk collection, storage, handling and feeding. In order to maximise the energy babies receive, it is crucial to ensure that mothers empty their breasts as thoroughly as possible during each expression session to ensure that fat rich milk is obtained (Milk Expression in Jones and King, 2005a) (Fig. 2. Photo. Increase in fat in milk samples collected every 60 s during a 15 min breast expressing using an electric breast pump). If mothers are expressing more than required at each feed, preterm infants should be fed on hind milk. (Hind milk is the fat rich milk obtained towards the end of a milk expression period). The fat concentration in hind milk is two to three times higher that it is if all the milk is used for feeding (Meier et al., 2010). Simply dividing each milk expression into two parts and using the second part and storing the first, will ensure a baby will receive milk with a higher fat content. (An example can be given: a mother expresses 80 mL per breast per expression. She should express the first 40 mL into bottle 1. The remainder of that expression per breast should be expressed into bottle 2. Bottle 2 should be fed to the baby). Since fat adheres to both containers and tubing it is very important to ensure that milk is given freshly expressed or warmed to body temperature prior to feed and the container is gently agitated to ensure the mixing of lipid globules. After the milk has been removed from the container, use a syringe to remove any milk fat that has adhered to crevices in the container and the lid (Meier et al., 2010). If babies are receiving continuous feeds never deliver the milk at less than 4 mL/h and tilt the syringe to allow fat delivery first. It is also important to keep tubing to a minimum length to minimise fat loss, and change from continuous to bolus feedings as soon as possible. Once milk production is established, mothers often decrease the intervals between expressions. It is vital to remember that milk removed after longer intervals is often lower in fat, than milk removed after shorter-between-expression
186 Table 4
E. Jones et al. Composition of breast milk fortifiers in the UK and Ireland.
Composition of recommended dose Recommended dose per 50 ml Energy Protein (source cow’ milk) Carbohydrate Fat Vitamin A Vitamin D Vitamin E Vitamin C Thiamin Riboflavin Niacin VitaminB6 Folic acid Vitamin B12 Biotin Pantothenic acid Vitamin K Sodium Calcium Phosphorus Magnesium Iron Zinc Iodine Potassium Chloride Manganese Copper Osmolality when added to EBM
Unit
kcal g g g ugRE ug mg mg mg mg mg mg ug ug ug mg ug mg mg mg mg mg ug mg mg ug ug mOsmol/kg
Nutriprem breast milk fortifier nutrica
SMA Gold Prem breast milk fortifier wyeth
2.2 g per sachet 8 0.6 (partially hydrolysed)
2 g per sachet 7.3 0.5 (whole protein whey based) 1.2 0.1 135 3.8 1.5 20 0.11 0.13 1.8 0.13 15 0.15 0.75 0.45 5.5 18 1.1 0.7 1.5 0 0.13 0 0.4 8.5 0 0 360
1.4 0 116 2.5 1.3 6 0.07 0.09 1.3 0.06 15 0.1 1.3 0.38 3.2 18 33 19 2.5 0 0.3 5.5 12 13 4.1 18 450
intervals. For some mothers, the longest interval is during the night-time sleep. If the mother’s total milk volume is adequate, do not feed the milk removed after long between-interval milk expression (Meier et al., 2010). This milk can be frozen for later use, and the baby should be feed with the milk from shorter between interval expressions. This milk will tend to be higher in
Table 5 milk.
calories. If the mothers total milk production does not allow the freezing of the longer between interval milk, then advice the mother to separate the first expression (after a long interval) into
Nutritional composition of mature breast
Nutrients per
/100 ml
Kcal Protein g CHO g Fat g
69 1.3 7.2 4.1
kcal (%)/100 ml from individual nutrients 5(7%) 27(39%) 37(54%)
Fig. 2 (Photo) Increase in fat in milk samples collected every 60 s during a 15 min expression using an electric breast pump.
Managing slow growth in preterm breastfed infants hindmilk segments to maximise the caloric value (Meier et al., 2010).
Strategies to promote adequate milk intake during the transition from tube to breast Most early preterm breastfeeding problems are directly related to immaturity and inconsistency. Preterm infants are often incapable of rhythmic suckling, which may inhibit the milk ejection reflex and restrict milk intake (Transition from tube to breast in Jones and King, 2005b). Unless milk ejection is triggered the amount of milk an infant receives may be insufficient to stimulate the swallow reflex. This will make it very difficult for a baby to progress from isolated suckles to nutritive suckling. Therefore, it is important to offer the breast with the best flow first, so that the infant is more able to get into the rhythm of the chained suckle-swallow response. Unless a baby feeds consistently with slow deep sucks and pauses for more than 10 min, a supplement will be needed post-breastfeed. Occasionally a preterm nipple shield is a useful tool. This is especially helpful when an infant has demonstrated suction pressures too weak to retain the nipple in the mouth during feeding. The use of the shield will provide a uniform rigid structure that extends into the oral cavity, thus allowing more tactile stimulation (Meier et al., 2000). As a result, breast attachment can be sustained and the infant is able to respond by suckling vigorously, thus compressing breast tissue. This will facilitate the accumulation of milk in the shield during the pauses in suckling, making it available to the infant when suckling resumes. When the baby becomes larger and stronger, mothers should be encouraged to wean off the device to promote more effective mammary stimulation and effective milk transfer. Some mothers become conditioned to manual expression. Even when a preterm infant’s suckling pattern matures, some mother’s experience a significant delay in milk ejection when an infant is put to the breast. Sometimes it is necessary to place an infant on one breast and a pump on the other in order to provide enough stimulation to trigger the milk ejection reflex (Jones and Spencer, 2005). Often the infant will respond by suckling eagerly and for a sustained period of time. Gradually as the effectiveness of suckling matures, the milk ejection reflex will become conditioned to infant response. Ensuring correct attachment and positioning is also vital to ensure that the baby is able
187 to obtain milk effectively and that nipple tissue is not traumatised. During the establishment of breastfeeding it is crucial that a mother continues to express her breast milk post feeds, in order to ensure that her milk supply does not diminish. A baby who is breastfeeding effectively suckles vigorously and swallows regularly. The baby should take long sucks rhythmically and it is normal for baby’s to pause from time to time. It can be very helpful to use breast compression during a feed to speed milk flow and to ensure the breast is fully drained (Jones and Spencer, 2005). As the infant becomes more functionally adept at feeding, the mother should not be encouraged to limit feeds to a prescribed number of minutes or to a strict feeding schedule. However, it is important to remember that a preterm baby’s ability to breastfeed is maturationally dependent. Many infants are not capable of self-regulation until they are between 36e38 weeks gestation. A full breastfeeding assessment must be made prior to discharge. Signs that a baby might not be feeding well include:
Static or weight loss Fewer wet nappies than expected Fewer than 2 in 24 h or hard constipated stool Fewer than 8 feeds in 24 h Baby unsettled after feeding Baby comes on and off the breast frequently during the feed Baby consistently feeds for less than 5 min Jaundice worsening or not improving Strategies to improve infant milk intake include both observing the baby feeding at the breast and reviewing the mothers milk supply. Unless a mother has a good milk supply, then it is important to ensure that the second breast is offered at each breastfeed. This will help to improve the volume of milk a baby receives at each feed, while boosting milk production. If a mother has an abundant supply, then it can be helpful for the mother to express some milk prior to the feed. This will ensure that the baby is able to reach the fat rich milk which is obtained towards the end of a feed. This will to improve the calorie content of each feed. Occasionally babies simply do not have the energy and endurance to feed effectively at each breastfeed and struggle to obtain the large volumes of breast milk they need to ensure good growth. In this instance, a mother will need to continue to express her breast milk to ensure supplementary feeds can be given. Some units in the UK and Ireland discharge infants with nasogastric tubes still in situ, which facilitate both top
188
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up feeds following poor breastfeeds and supplementary feeding. Babies who receive post discharge neonatal dietician support, occasionally still receive breast milk fortifiers post discharge to ensure adequate growth. The fortifier can be administered in a small amount of breast milk prior to breastfeeding or added to breast milk, which can be given via a cup feed. If there is inadequate breast milk then supplementary feeds are used. These may be either a follow on preterm formula or a high energy formula depending on clinical needs. Close monitoring is essential to ensure that the supplementary feeds that are used are kept to the minimum. The goal of the neonatal team is to support strategies that promote the establishment of breastfeeding, while supporting infant weight gain and growth.
References Agostini, C., Buonocare, G., Carnielli, V.P., De-Curtis, M., et al., 2010. Enteral nutrient supply for preterm infants: commentary from the European Society for Paediatric Gastroenterology, Hepatology and Nutrition Committee on Nutrition. Journal of Pediatric Gastroenterology and Nutrition 50 (1), 85e91. FSA, 2002. McCance and Widdowson’s the Composition of Foods. Sixth Summary Edition. Food Standards Agency, RSC Publishing.
Jones, E., Bell, S., Shankar, S., 2012. An audit of preterm nutritional intake using a human milk analyser. Infant 8 (3), 91e94. Jones, E., King, C. (Eds.), 2005a. Milk Expression in Feeding and Nutrition in the Preterm Infant. Elsevier, Churchill Livingstone, pp. 76e77. Jones, E., King, C. (Eds.), 2005b. Transition from Tube to Breast in Feeding and Nutrition in the Preterm Infant. Elsevier, Churchill Livingston, pp. 156e157. Jones, E., Spencer, S.A., 2005. How to achieve successful preterm breastfeeding. Infant 1 (4), 14e17. King, C., Bell, S., November 2010. Discussion paper on the use of breast milk fortifiers in the feeding of preterm infants. Bliss Briefings. http://www.bliss.org.uk/improving-care/ professional-development/bliss-briefings/. Meier, P., Brown, L., Hurst, N., 2000. Nipple shields for preterm infants, effect on milk transfer and duration of breastfeeding. Journal of Human Lactation 16, 174e175. Meier, P., Engstrom, J., Patel, A., Jegier, B., Bruns, N., 2010. Improving the use of human milk during and after the NICU stay. Clinics in Perinatology 37 (1), 217e245. Nagaya, K., Tanaka, S., Kitajima, H., Fujimura, M., 2007. The corrected blood urea nitrogen predicts the developmental quotient of extremely low-birth-weight infants at the corrected age of 36 months. Early Human Development 83, 285e291. Royal College of Paediatrics and Child Health, 2009. UK, WHO Neonatal and Infant Close Monitoring Charts. www.rcpch.ac. uk/. Weber, A., Loui, A., Jochum, F., Bu ¨hrer, C., Obladen, M., 2001. Breast milk from mothers of very low birthweight infants: variability in fat and protein content. Acta Paediatrics 90, 772e775.
Available online at www.sciencedirect.com
www.elsevier.com/jneo
Managing slow growth in preterm infants fed on human milk Elizabeth Jones*, Sue Bell, Shiva Shankar Neonatal Intensive Care Unit, University Hospital of North Staffordshire, Newcastle Road, Stoke-on-Trent ST4 6QG, UK Available online 21 May 2013
KEYWORDS Human milk; Expressed breast milk; Protein intake; Breast milk fortifier; Preterm breastfeeding
Abstract The benefits of human milk for the preterm infant are well documented. However, after the first 2e3 weeks following delivery, the nutrient content in human milk may be insufficient to promote growth in the rapidly growing preterm infant. The challenge for the neonatal team is to develop clinical strategies that support the use of human milk and the establishment of breastfeeding, while supporting infant weight gain and growth. A range of clinical strategies are required to monitor growth and manage sub-optimal growth. Over 50% of the energy babies receive from mature breast milk is from lipids. Hence it is very important to minimise fat loss during milk collection, handling and storage while giving expressed breast milk to maximise growth. Once breastfeeding has been established an assessment should be performed to ensure that attachment and positioning is optimal and that feeding care plans are in place, to ensure infant growth does not falter following discharge from hospital. ª 2013 Neonatal Nurses Association. Published by Elsevier Ltd. All rights reserved.
Importance of breast milk The benefits of human milk in preterm infants are well documented (Agostini et al., 2010). Human milk contains immunological factors that potentially reduce the incidence of sepsis and necrotising enterocolitis (Agostini et al., 2010). Strong evidence also suggests that the absorption rate of * Corresponding author. E-mail address: [email protected] (E. Jones).
nutrients from human milk is better than from breast milk substitutes. The enzymes, hormones and growth factors found in human milk play important roles in gastrointestinal growth and maturation and may accelerate the establishment of enteral feeding in infants fed human milk (Meier et al., 2010). The constituents of breast milk have three main functions: To provide nutrition To give immune protection
1355-1841/$ - see front matter ª 2013 Neonatal Nurses Association. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jnn.2013.04.004
Managing slow growth in preterm breastfed infants To promote development Some constituents accomplish all three. Mothers’ own expressed breast milk provides the ideal transition to extra-uterine nutrition. Preterm infants have higher nutrient requirements than term infants, and after the first 2e3 weeks of lactation the protein content of human milk is usually insufficient to meet the
Fig. 1
183 nutritional demands of rapidly growing preterm infants (Weber et al., 2001). The majority of preterm infants born <34 weeks gestation exclusively fed on human milk are at risk of slower rate of weight gain than in utero. This deficit in growth is largely due to the additional protein requirements needed to accelerate preterm growth. If energy is also insufficient then the infant will use protein for energy, which will compound the deficit further. If
UK WHO growth chart.
184
E. Jones et al.
this is uncorrected the deficit in protein and/or energy can effect both growth and neurocognitive development in babies born preterm (Nagaya et al., 2007). Therefore, the priority for neonatal care must be to develop strategies that support both the feeding of human milk while supporting adequate infant growth. Table 1 illustrates that the protein requirements for preterm infants are substantially higher than those for babies born at term (Agostini et al., 2010).
Assessing preterm infant growth In order to assess optimal growth on an individual basis, head circumference, length and weight need to be plotted weekly on a growth chart (Fig. 1 e UK WHO Growth Chart, 2009). This will give a visual tool of overall growth, and it will show which centile the infant is on following the initial diuresis which occurs post-delivery. These centiles can be used for assessing poor weight gain and growth. The growth parameters shown to indicate intrauterine growth should only be used as a guide. The growth chart will enable a more accurate assessment on an individual basis. Table 2 shows the average growth in utero for head circumference, length and weight gain (Agostini et al., 2010). The following factors can contribute to a diagnosis of poor growth: Progressive weight loss or static weight over several days (other than the early postnatal period) When weight velocity alone decreases over 2 weeks (Decreased growth velocity occurs when growth continues but at a lower rate than is needed to follow the centile). Once a diagnosis of poor growth has been established nutritional supplementation is often required, particularly in situations where it is hard to deliver high volumes of breast milk. In the United Kingdom and Ireland, additional nutrients are usually given via a multi-nutrient fortifier. The guidelines in Table 3 are based on a briefing paper of what constitutes current clinical practice in the UK and Ireland (King and Bell, 2010). An array of
Table 1
Table 2
Optimal growth in preterm infants.
The average weight gain for preterm growth is 15e20 g/kg day 30 g a day if >2 kg Length is 0.9 cm per week Head circumference is 0.9 cm per week
nutrients and macronutrients have been added to breast milk fortifiers, in order to maximise infant growth. Table 4 illustrates the range of nutrients that have been included in most commercial breast milk fortifiers used in the UK. It is very important to reassure mothers that breast milk is vitally important to her baby and that she should continue to express her milk. Meier et al. (2010) describe human milk to mothers ‘as a perfect medicine that only a mother can provide’. It can be helpful to explain that preterm babies cannot always take adequate volumes of breast milk and that they have very high demands for protein, minerals and vitamins. Therefore, it is sometimes necessary to supplement babies for a short time simply to help a baby to grow.
Managing sub-optimal growth Since human milk is very variable in composition, the analysis of mothers’ own expressed breast milk is an ideal tool to monitor infant nutrition on an individual basis (Jones et al., 2012). If the protein content is <2.3 g/100 mL volumes should be increased to above 150 mL/kg/day, whenever possible, to avoid fortification. If protein is the limiting nutrient then the addition of a breast milk fortifier can improve growth. If growth remains poor after the addition of a fortifier, a hind milk policy can be used if the mother has a good milk supply. If this fails to promote growth then the addition of preterm formula in conjunction with breast milk can be utilised. High energy formula is also prescribed to promote growth in fluid restricted infants. Caution is needed when using high energy formulas as the nutritional composition is designed specifically for term infants. It is important to remember that not all suboptimal growth and weight gain is attributed to
Protein and energy requirement comparisons (term/preterm).
Daily recommendation Energy (kcal/kg/day) Protein (g/kg/day)
Preterm <1 kg 110e135 3.5e4.5
Preterm e 1e1.8 kg 110e135 3.5e4.0
Term e 0e3 months (DHSS ’91) 115e100 2.1
Managing slow growth in preterm breastfed infants Table 3
Guidelines for the use of breast milk fortifiers.
Criteria for starting fortification All babies <1.5 kg birth weight and <34 weeks Consider babies 1.5e2 kg birth weight and <34 weeks Babies >2 kg birth weight are unlikely to need BMF Plus; Receiving 50 per cent total feeds as breast milk Tolerating feed volumes at a minimum of 150 ml/kg/ day e preferably 180 ml/kg Serum urea < 4 mmol/l and falling What to add Commercially available fortifier following dose according to manufacturer’s instructions How to add Use manufacturers’ instructions Warm for as brief a period as possible and avoid temperatures >37 C Mix well but avoid vigorous shaking Fortify the minimum volume possible, and use before fortifying more Consider starting at half strength for 24 h if baby at risk of poor tolerance Monitoring and additional supplementation Weekly weight, length and head circumference If growth falters calculate nutrient intake and compare with recommended intakes Weekly serum phosphate, calcium, sodium and alkaline phosphatase Weekly serum urea taking into account possible increases with dehydration compromised renal function, sepsis, steroid therapy and inadequate non protein energy intake If urea within normal range but growth is faltering consider use of hind milk Give iron supplement between four to six weeks Criteria for stopping fortification On <50 per cent total feeds EBM and growth satisfactory If growth not satisfactory carry on BMF until <25 per cent total feeds EBM Able to fully demand breast feed At discharge together with satisfactory growth Assess babies individually to see if BMF post discharge
inadequate nutrition. The following indices need to be part of the assessment prior to planning any nutritional intervention:
Sodium depletion Anaemia Steroid treatment Sepsis/trauma Fluid imbalance Reflux
185 In addition, conditions such as patent ductus arteriosus and chronic lung disease can increase nutritional requirements, and cholestasis can cause the malabsorption of nutrients.
Practical methods for preserving human milk lipids (fat) Over 50% of the energy babies receive from human milk is from lipids (fat) (Table 5 e McCance and Widdowson, 2002). By using very practical strategies, neonatal nurses can minimise lipid loss during the processes of milk collection, storage, handling and feeding. In order to maximise the energy babies receive, it is crucial to ensure that mothers empty their breasts as thoroughly as possible during each expression session to ensure that fat rich milk is obtained (Milk Expression in Jones and King, 2005a) (Fig. 2. Photo. Increase in fat in milk samples collected every 60 s during a 15 min breast expressing using an electric breast pump). If mothers are expressing more than required at each feed, preterm infants should be fed on hind milk. (Hind milk is the fat rich milk obtained towards the end of a milk expression period). The fat concentration in hind milk is two to three times higher that it is if all the milk is used for feeding (Meier et al., 2010). Simply dividing each milk expression into two parts and using the second part and storing the first, will ensure a baby will receive milk with a higher fat content. (An example can be given: a mother expresses 80 mL per breast per expression. She should express the first 40 mL into bottle 1. The remainder of that expression per breast should be expressed into bottle 2. Bottle 2 should be fed to the baby). Since fat adheres to both containers and tubing it is very important to ensure that milk is given freshly expressed or warmed to body temperature prior to feed and the container is gently agitated to ensure the mixing of lipid globules. After the milk has been removed from the container, use a syringe to remove any milk fat that has adhered to crevices in the container and the lid (Meier et al., 2010). If babies are receiving continuous feeds never deliver the milk at less than 4 mL/h and tilt the syringe to allow fat delivery first. It is also important to keep tubing to a minimum length to minimise fat loss, and change from continuous to bolus feedings as soon as possible. Once milk production is established, mothers often decrease the intervals between expressions. It is vital to remember that milk removed after longer intervals is often lower in fat, than milk removed after shorter-between-expression
186 Table 4
E. Jones et al. Composition of breast milk fortifiers in the UK and Ireland.
Composition of recommended dose Recommended dose per 50 ml Energy Protein (source cow’ milk) Carbohydrate Fat Vitamin A Vitamin D Vitamin E Vitamin C Thiamin Riboflavin Niacin VitaminB6 Folic acid Vitamin B12 Biotin Pantothenic acid Vitamin K Sodium Calcium Phosphorus Magnesium Iron Zinc Iodine Potassium Chloride Manganese Copper Osmolality when added to EBM
Unit
kcal g g g ugRE ug mg mg mg mg mg mg ug ug ug mg ug mg mg mg mg mg ug mg mg ug ug mOsmol/kg
Nutriprem breast milk fortifier nutrica
SMA Gold Prem breast milk fortifier wyeth
2.2 g per sachet 8 0.6 (partially hydrolysed)
2 g per sachet 7.3 0.5 (whole protein whey based) 1.2 0.1 135 3.8 1.5 20 0.11 0.13 1.8 0.13 15 0.15 0.75 0.45 5.5 18 1.1 0.7 1.5 0 0.13 0 0.4 8.5 0 0 360
1.4 0 116 2.5 1.3 6 0.07 0.09 1.3 0.06 15 0.1 1.3 0.38 3.2 18 33 19 2.5 0 0.3 5.5 12 13 4.1 18 450
intervals. For some mothers, the longest interval is during the night-time sleep. If the mother’s total milk volume is adequate, do not feed the milk removed after long between-interval milk expression (Meier et al., 2010). This milk can be frozen for later use, and the baby should be feed with the milk from shorter between interval expressions. This milk will tend to be higher in
Table 5 milk.
calories. If the mothers total milk production does not allow the freezing of the longer between interval milk, then advice the mother to separate the first expression (after a long interval) into
Nutritional composition of mature breast
Nutrients per
/100 ml
Kcal Protein g CHO g Fat g
69 1.3 7.2 4.1
kcal (%)/100 ml from individual nutrients 5(7%) 27(39%) 37(54%)
Fig. 2 (Photo) Increase in fat in milk samples collected every 60 s during a 15 min expression using an electric breast pump.
Managing slow growth in preterm breastfed infants hindmilk segments to maximise the caloric value (Meier et al., 2010).
Strategies to promote adequate milk intake during the transition from tube to breast Most early preterm breastfeeding problems are directly related to immaturity and inconsistency. Preterm infants are often incapable of rhythmic suckling, which may inhibit the milk ejection reflex and restrict milk intake (Transition from tube to breast in Jones and King, 2005b). Unless milk ejection is triggered the amount of milk an infant receives may be insufficient to stimulate the swallow reflex. This will make it very difficult for a baby to progress from isolated suckles to nutritive suckling. Therefore, it is important to offer the breast with the best flow first, so that the infant is more able to get into the rhythm of the chained suckle-swallow response. Unless a baby feeds consistently with slow deep sucks and pauses for more than 10 min, a supplement will be needed post-breastfeed. Occasionally a preterm nipple shield is a useful tool. This is especially helpful when an infant has demonstrated suction pressures too weak to retain the nipple in the mouth during feeding. The use of the shield will provide a uniform rigid structure that extends into the oral cavity, thus allowing more tactile stimulation (Meier et al., 2000). As a result, breast attachment can be sustained and the infant is able to respond by suckling vigorously, thus compressing breast tissue. This will facilitate the accumulation of milk in the shield during the pauses in suckling, making it available to the infant when suckling resumes. When the baby becomes larger and stronger, mothers should be encouraged to wean off the device to promote more effective mammary stimulation and effective milk transfer. Some mothers become conditioned to manual expression. Even when a preterm infant’s suckling pattern matures, some mother’s experience a significant delay in milk ejection when an infant is put to the breast. Sometimes it is necessary to place an infant on one breast and a pump on the other in order to provide enough stimulation to trigger the milk ejection reflex (Jones and Spencer, 2005). Often the infant will respond by suckling eagerly and for a sustained period of time. Gradually as the effectiveness of suckling matures, the milk ejection reflex will become conditioned to infant response. Ensuring correct attachment and positioning is also vital to ensure that the baby is able
187 to obtain milk effectively and that nipple tissue is not traumatised. During the establishment of breastfeeding it is crucial that a mother continues to express her breast milk post feeds, in order to ensure that her milk supply does not diminish. A baby who is breastfeeding effectively suckles vigorously and swallows regularly. The baby should take long sucks rhythmically and it is normal for baby’s to pause from time to time. It can be very helpful to use breast compression during a feed to speed milk flow and to ensure the breast is fully drained (Jones and Spencer, 2005). As the infant becomes more functionally adept at feeding, the mother should not be encouraged to limit feeds to a prescribed number of minutes or to a strict feeding schedule. However, it is important to remember that a preterm baby’s ability to breastfeed is maturationally dependent. Many infants are not capable of self-regulation until they are between 36e38 weeks gestation. A full breastfeeding assessment must be made prior to discharge. Signs that a baby might not be feeding well include:
Static or weight loss Fewer wet nappies than expected Fewer than 2 in 24 h or hard constipated stool Fewer than 8 feeds in 24 h Baby unsettled after feeding Baby comes on and off the breast frequently during the feed Baby consistently feeds for less than 5 min Jaundice worsening or not improving Strategies to improve infant milk intake include both observing the baby feeding at the breast and reviewing the mothers milk supply. Unless a mother has a good milk supply, then it is important to ensure that the second breast is offered at each breastfeed. This will help to improve the volume of milk a baby receives at each feed, while boosting milk production. If a mother has an abundant supply, then it can be helpful for the mother to express some milk prior to the feed. This will ensure that the baby is able to reach the fat rich milk which is obtained towards the end of a feed. This will to improve the calorie content of each feed. Occasionally babies simply do not have the energy and endurance to feed effectively at each breastfeed and struggle to obtain the large volumes of breast milk they need to ensure good growth. In this instance, a mother will need to continue to express her breast milk to ensure supplementary feeds can be given. Some units in the UK and Ireland discharge infants with nasogastric tubes still in situ, which facilitate both top
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up feeds following poor breastfeeds and supplementary feeding. Babies who receive post discharge neonatal dietician support, occasionally still receive breast milk fortifiers post discharge to ensure adequate growth. The fortifier can be administered in a small amount of breast milk prior to breastfeeding or added to breast milk, which can be given via a cup feed. If there is inadequate breast milk then supplementary feeds are used. These may be either a follow on preterm formula or a high energy formula depending on clinical needs. Close monitoring is essential to ensure that the supplementary feeds that are used are kept to the minimum. The goal of the neonatal team is to support strategies that promote the establishment of breastfeeding, while supporting infant weight gain and growth.
References Agostini, C., Buonocare, G., Carnielli, V.P., De-Curtis, M., et al., 2010. Enteral nutrient supply for preterm infants: commentary from the European Society for Paediatric Gastroenterology, Hepatology and Nutrition Committee on Nutrition. Journal of Pediatric Gastroenterology and Nutrition 50 (1), 85e91. FSA, 2002. McCance and Widdowson’s the Composition of Foods. Sixth Summary Edition. Food Standards Agency, RSC Publishing.
Jones, E., Bell, S., Shankar, S., 2012. An audit of preterm nutritional intake using a human milk analyser. Infant 8 (3), 91e94. Jones, E., King, C. (Eds.), 2005a. Milk Expression in Feeding and Nutrition in the Preterm Infant. Elsevier, Churchill Livingstone, pp. 76e77. Jones, E., King, C. (Eds.), 2005b. Transition from Tube to Breast in Feeding and Nutrition in the Preterm Infant. Elsevier, Churchill Livingston, pp. 156e157. Jones, E., Spencer, S.A., 2005. How to achieve successful preterm breastfeeding. Infant 1 (4), 14e17. King, C., Bell, S., November 2010. Discussion paper on the use of breast milk fortifiers in the feeding of preterm infants. Bliss Briefings. http://www.bliss.org.uk/improving-care/ professional-development/bliss-briefings/. Meier, P., Brown, L., Hurst, N., 2000. Nipple shields for preterm infants, effect on milk transfer and duration of breastfeeding. Journal of Human Lactation 16, 174e175. Meier, P., Engstrom, J., Patel, A., Jegier, B., Bruns, N., 2010. Improving the use of human milk during and after the NICU stay. Clinics in Perinatology 37 (1), 217e245. Nagaya, K., Tanaka, S., Kitajima, H., Fujimura, M., 2007. The corrected blood urea nitrogen predicts the developmental quotient of extremely low-birth-weight infants at the corrected age of 36 months. Early Human Development 83, 285e291. Royal College of Paediatrics and Child Health, 2009. UK, WHO Neonatal and Infant Close Monitoring Charts. www.rcpch.ac. uk/. Weber, A., Loui, A., Jochum, F., Bu ¨hrer, C., Obladen, M., 2001. Breast milk from mothers of very low birthweight infants: variability in fat and protein content. Acta Paediatrics 90, 772e775.
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