Nutrition and Feeding

Christopher Tomlinson, MB ChB BSc PhD

The material presented here was first published in the Residents’ Handbook of Neonatology, 3rd edition, and is reproduced here with permission from PMPH USA, Ltd. of New Haven, Connecticut and Cary, North Carolina.

The birth of a preterm infant is regarded as a nutritional emergency. With the abrupt cessation of placental transfer of nutrients and the lack of any substantial store of energy, the preterm infant is immediately dependent on an exogenous supply of macro and micronutrients. The goal of the health care team in the NICU is attain growth of our patients that is equivalent to intrauterine growth rates. This chapter will outline parenteral and enteral nutrient requirements of preterm patients, and discuss the tools we have available to optimize their growth.


Nutrition Assessment

Neonatal nutrition assessment consists of a comprehensive evaluation of the infant’s growth status, dietary intake in relation to estimated requirements, biochemical indices and clinical condition or factors that affect the infant’s nutritional status.

  • Growth is a primary indicator of nutritional adequacy.
  • Growth charts are used to compare the infant’s growth pattern to the reference standard.
  • Expected intrauterine rate of weight gain is 12-16 g/kg/day.


Nutrient Requirements

Recommended nutrient intakes for premature infants receiving enteral and parenteral nutrition are available to assist clinicians in providing optimal nutritional care during different stages of postnatal life (refer to Table 8.1 and 8.2).

A basic starting energy intake to gain weight is 105-135 kcal/kg/d, not accounting for modifications due to energy expenditure. But composition of this energy is also important to balance (See Table 8.1).


Table 8-1  Recommended Daily Nutrient Intakes for Premature Infants
Nutrient Transition Infant

 (birth to 7 days)

Stable-Growing Infant
Water (mL/kg) Variable 120-200


Energy (kJ/kg)* 292-334 438-563
(kcal/kg) (70-80) (105-135)
Protein* (g/kg) 2.0-3.0 3.5-4.5 (BW <1000 g)
3.0-4.0 (BW 1000 g)
Fat (g/kg) 1.0-3.6 4.5-6.8
Fat* (% of energy) 10-50 40-55
Carbohydrate (g/kg) 5.0-20.0 7.5-15.5
(3.5-16.5 mg/kg per min)


Calcium (mmol/kg) 1.5-2.0 4.0-6.0
Phosphorus (mmol/kg) 1.0-1.5 2.5-3.8
Magnesium (mmol/kg) 0.20-0.25 0.20-0.40
Sodium (mmol/kg) 1.0-3.0 2.5-4.0
Chloride (mmol/kg) 1.0-3.0 2.5-4.0
Potassium (mmol/kg) 2.5-3.5 2.5-3.5
Iron (mg/kg) 0 (start 6 to 8 wk after birth)
▪     3.0-4.0 (BW <1000 g)
▪     2.0-3.0 (BW 1000 g)
Zinc (mol/kg) 6.5 7.7-12.3
Copper* (mol/kg) 1.1-1.9 1.1-1.9
Selenium* (mol/kg) 0.04-0.06 0.04-0.06
Chromium* (nmol/kg) 1.0-1.9 1.0-1.9
Manganese* (nmol/kg) 10-20 10-20
Molybdenum* (nmol/kg) 2.0-4.0 2.0-4.0
Iodine* (mol/kg) 0.20 0.25-0.50


Vitamin D (IU) ▪     40-120 (BW <1000 g) 400
▪     40-260 (BW 1000 g) 400
Vitamin A (g/kg) 450 ▪     450 (BW <1000g)
▪     200-450 (BW 1000 g; lower intake for larger infants)
Vitamin E* (mg/kg) 0.5-0.9 0.5-0.9
Vitamin C (mg/kg) 6-10 6-10
Vitamin B1 (mg) 0.04-0.05 0.04-0.05
Vitamin B2 (mg/kg) 0.36-0.46 0.36-0.46
Vitamin B6 (mg/g of protein) 0.015 0.015
Vitamin B12 (g) 0.15 0.15
Niacin NEII (5000 kJ) 8.6 8.6
Folate (g) 50 50
Biotin (g/kg) 1.5 1.5
Pantothenic acid (mg/kg) 0.8-1.3 0.8-1.3
* Amount differs if the infant is fed parenterally.

In specific clinical situations, sodium and chloride may need to be omitted or intake increased for short periods.

May be omitted from parenteral nutrition during the transition period.

For infants fed formula, this amount may differ.

II  Niacin equivalents.

Adapted from Nutrition Committee, Canadian Paediatric Society (1995)


Parenteral Nutrition

Indications for Parenteral Nutrition Support

  • Infants of BW < 1000g
  • Infants of BW of 1000 to 1500g who cannot be expected to tolerate full oral feeds within 4 to 7 days; avoid glucose only regimens beyond 24 hours age.
  • Patients with other conditions precluding enteral feeding for similar duration as described above, such as NEC, obstructive lesions of the GI tract, many post-surgical infants.
  • Infants unable to tolerate sufficient enteral feedings to initiate weight gain.


Parenteral Nutrient Requirements

Table 8-2  Parenteral Nutrient Requirements
Components Daily Amount
Fluid 140-160 mL/kg
Glucose 8-18 g/kg
Lipid (20% SMOF emulsion) 1.0 -4 g/kg
Amino Acid mixture 2-4 g/kg
Sodium (chloride / acetate) 2-4 mmol/kg
Potassium (phosphate/chloride/acetate) 2-4 mmol/kg
Acetate chloride ratio >1
Calcium (gluconate or chloride) 1-2 mmol/kg
Phosphorus (monobasic potassium phosphate) 1- 2 mmol/kg
Magnesium (sulphate) 0.125 mmol/kg
M.V.I. Pediatric (multivitamin) 2 mL/kg (max 5 mL/d)
Zinc (sulphate) 200-400 ug/kg
Copper (sulphate) 40 ug/kg


Guidelines for Parenteral Nutrition Support

An amino acid intake of at least 1-1.5g/kg/day is required to prevent nitrogen loss.

All in one admixtures decrease the number of infusion pumps/drivers, however present physico-chemical alterations (larger size of fat globules, insoluble salts) with hazards.


1. Protein
Preterm infants: BW >1000g: 3 – 3.5 g/kg/d
BW <1000g: 3.5 – 4 g/kg/d
Term infants:       2.5 – 3 g/kg/d


  • The preterm infant should receive 2 to 3 g/kg/d within the first 24 hours of age; subsequently increase by 0.5 g/kg/d.
  • Monitor serum urea in metabolically unstable infants, however, rapid changes in urea will more likely be due to fluid shifts rather than reflecting iatrogenic balance
  • Reduce IV amino acids for severe PN – induced cholestasis.
  • For preterm infants receiving adequate non-protein energy >70 kcal/kg/d, nitrogen intake is the main determinant of nitrogen retention.
  • If the energy intake of preterm infants is <50 kcal/kg/d, nitrogen will not be retained effectively.


2. Carbohydrate
Glucose concentrations:
initial:         5-7.5%
maximum: 12.5% via peripheral line
20% in central line (based on osmolarity)


 Table 8.3   Recommended Glucose Infusion Rates (GIR)
BW <1000g Term infant
Goal 12-16 g/kg/d (8-12 mg/kg/min) 15-18 g/kg/d (10-13mg/kg/min)
Upper Limit 16 g/kg/d (12 mg/kg/min) 18 g/kg/d (13 mg/kg/min)


  • Carbohydrate intake must be calculated daily, including carbohydrate content of all intravenous fluids.
  • Hypo- and hyperglycemia are frequent complications in the very low birth weight infants.
  • The range of practice to deal with early hyperglycaemia includes:

(a) administration of intravenous amino acids has been shown to decrease glucose concentrations in ELBW infants, presumably by enhancing endogenous insulin secretion;

  • lowering glucose intake until hyperglycemia resolves while avoiding hypotonic fluid administration; ensure not to drop below a maintenance glucose intake equal to endogenous glucose production rate (4-6 mg/kg/min);

(c) initiating exogenous insulin therapy (0.05 to 0.3 U/kg/h), requires special attention because of the risk of hypoglycemia; and in absence of amino acid leads to elevated lactate and metabolic acidosis.


3. Lipids

  • A concentrated source of energy in a small volume of fluid.
  • A source of essential fatty acids (0.5g/kg/d to prevent essential fatty acid =EFA deficiency).
  • Lipid infusions can be initiated within the first 24 hours; increase slowly (table 8.4); monitor serum triglycerides (Maintain < 2mmol/L – see table 8.5).
  • 10% emulsions are not used in newborns, use 20%.
  • Infants with septicemia may have delayed lipid clearance and increased free fatty acids; if elevated triglycerides, reduce infusion to ≤2g/kg/day until the septicemia is resolved – some stop lipids for 24 hours.
  • Reduce (or stop) lipids in any hyperbilirubinemia (especially PN-induced cholestasis.

An amino acid intake of at least 1-1.5g/kg/day is required to prevent nitrogen loss

Table 8.4  Recommendation for Dose of Intravenous Lipid  Emulsion
Gestation Initial dosing Increments* Maximum
<28 wk 1 g/kg/d 1 g/kg/d 3-4 g/kg/d
28-32 wk 1 g/kg/d 1 g/kg/d 3-4 g/kg/d
33-36 wk 1-2 g/kg/d 1 g/kg/d 4 g/kg/d
>37 wk 2 g/kg/d 1 g/kg/d 4 g/kg/d

 *Advance as tolerated; serum triglyceride concentrations up to 2mmol/L are acceptable


4. Vitamins

The ideal parenteral vitamin mixture for preterm infants is not known.

The main concern with most IV vitamin preparations is their high propylene glycol and sorbitol content as well as their contribution to the generation of peroxides

The Pediatric preparation MVI 12 Pediatric is low in propylene glycol.

Table 8.5  Composition of Intravenous Vitamin Preparation
Components of MVI  Pediatric Amount per 5 mL
Vitamin A (IU) 2300
Vitamin B1 – thiamine (mg) 1.2
Vitamin B2  – riboflavin (mg) 1.4
Vitamin B6  – pyridoxine hydrochloride (mg) 1.0
Vitamin B12 – cyanocoblamine (ug) 1.0
Niacinamide (mg) 17
Vitamin C (mg) 80
Vitamin D (IU) 400
Vitamin E (IU) 7
d-Pantothenic acid (mg) 5
Biotin (ug) 20
Folic acid (mg) 0.14
Vitamin K (ug) 200


5. Complications of Parenteral Nutrition

Table 8.6  Common PN-Related Complications
Metabolic Hyper- and hypoglycaemia

Electrolyte disorders

Mineral disorders

Vitamin disorders


Essential fatty acid deficiency

Aluminum and chromium accumulation


Axotemia, hyperammonemia

Abnormal plasma aminograms

Catheter related Malposition, dislodgement, perforation organ or vessel, chylothorax,

hemothorax, phemothorax, thrombosis

Infections Sepsis (bacterial and fungal)

Endocarditis, osteomyelitis

Cholecystitis, nephritis

Local and skin infections

Other Cholestasis and cirrhosis

Bone disease


6. Monitoring of Parenteral Nutrition

In general, the following laboratory measures are required:

  • Acid-base status, electrolytes
  • Calcium, phosphorus
  • Glucose, triglycerides
  • BUN and creatinine
  • Liver function tests (protein, albumin, AST, ALT, bilirubin)
  • Hemoglobin, reticulocytes


Table 8.7  PN Monitoring Recommendations
Monitoring  Description Frequency Measure
Monitor until intakes and metabolic responses are stable Every 8-12 h Blood glucose, urine glucose
Daily Acid-base balance,

electrolytes, Ca

Twice Weekly BUN, creatinine, P,


Monitor once intakes an metabolic responses are stable Alternate week Ca, P, total protein, albumin, CBC, AST, ALT,  γGT, LDH, Mg, bilirubin, alk phos
After one month consider Fe, TIBC, ferritin, PT, PTT and trace elements


7. Special Considerations

Hyperglycemia (if associated with glycosuria)

  • Isolated glycosuria probably not of concern
  • Ensure infant not septic
  • Add insulin in a separate line while adjusting glucose concentration. Titrate insulin requirements with caution because of individual variation and the risk of hypoglycaemia.  Once insulin needs are constant, consider adding it to the PN solution with albumin (avoids adsorption to the plastics).


Optimizing the bioavailability of infused nutrients:

  • Protect PN solutions from daylight exposure (decreases peroxides generated by lipid).
  • Due to problems of solubility, calcium and phosphorus intakes cannot be increased to meet requirements without precipitation. Note that hypercalcemia (more specifically when associated with hypercalciuria) together with hypophosphoremia suggests bone resorption due to insufficient mineral intakes, especially inadequate phosphorus intake.  
  • Flocculation is rare but related to a disruption of the lipid emulsion; correct by modifying fluid and lipid concentrations.
  • Parenteral iron admixture is controversial because it is feared that it could contribute to oxidative reactions. For patients on long term PN requiring parenteral iron supplementation, use sources of bound iron (200 to 400 µg/kg/d).


Management of cholestasis

  • To reduce PN-related cholestasis, promote early feeding, administer ursodeoxycholic acid and reduce IV nutrient intakes especially IV lipid including trace elements.


8. Calculation of Caloric Equivalents of Parenteral Nutrients

Nutrient Caloric Equivalent
Protein* 1g = 4 kcal (biological value)
Dextrose 1 g = 3.4 kcal
Lipid (20% emulsion) 1 mL = 2 kcal

*1 g nitrogen = 6.25g protein


Enteral Nutrition

In clinical practice, feeding protocols vary widely between NICUs.

Feeding guidelines must account for gestational age, weight, and clinical condition.


Relative Contraindications to Enteral Feeding

Individual patients should be evaluated before feeds are initiated.  Some of the contraindications listed below have been extensively discussed elsewhere:

  • Impending or recent extubation
  • Acute respiratory failure particularly with spontaneous respiratory rate > 60/min
  • Metabolic acidosis
  • Post cardiac arrest
  • Hypotension and shock, use of high dose IV inotropes
  • Immediately before and after cardiac catheterization
  • Preoperatively (8h) and postoperatively (according to procedure and severity of illness)
  • Serious infections, especially if paralytic ileus suspected
  • Necrotizing enterocolitis (NEC), abdominal distension, and excessive gastric aspirates or bile-stained gastric aspirates
  • Severe asphyxia (Sarnat stages II and III)
  • Before and after exchange transfusion
  • Hydrops fetalis until stable (adjust weight by reference to standards for length, head circumference, and gestational age)


Minimal Enteral Nutrition (MEN) or Trophic Feeding

  • MEN is the administration of nutritionally inconsequential quantities of feed (12-24 mL/kg/day) while the main route of nutrition is parenteral
  • MEN has many physiologic and clinical benefits, such as promoting maturation of gut function, without an increased risk for NEC
  • Optimum timing for MEN remains unclear
  • Can be initiated in stable preterm infants <1000g between as soon as possible after birth, at 12-24 mL/kg/day (corresponds to 0.5 to 1 mL/hour for a 1 kg baby) Evidence shows that <30 mL/kg/d is well tolerated.
  • Mechanical ventilation or presence of umbilical arterial line are not contraindication
  • Feeding advancement (especially in ELBW) should not exceed 30 mL/kg/day due to the risk of NEC


Nutrition Guidelines for Infants <1000 g
  Parenteral Nutrition*  
Timing Protein Lipid Enteral Feeds
Day 1 1.5-2.5 g/kg/d 0.5-1 g/kg/d Trophic feeds
Day 2 2.5 g/kg/d 1 g/kg/d Trophic feeds

EBM 1 mL q12h

Day 3 3 g/kg/d 2 g/kg/d Feeds as per enteral feeding protocol once stable, see below
Day 4 3–3.5 g/kg/d 3 g/kg/d As above
>Day 4 3.5 g/kg/d 3.5 g/kg/d As above
>Week 3–4 Discontinue PN once full enteral feeds reached Once at full feeds, increase to 3000 kJ/L, then 3300 kJ/L using HMF if using EBM; if using formula, assess growth and evaluate need for increased calories
*Add electrolytes based on clinical and laboratory assessment. Protein and lipids not to exceed 4 g/kg/d.

†Monitor lipid levels when at 2 g fat/kg/d before increasing.


Nutrition Guidelines for Infants 1001–1500 g
Timing Parenteral Nutrition* Enteral Feeds
Protein Lipid
Day 1 2 g/kg/d 1 g/kg/d Trophic feeds
Day 2 3 g/kg/d 2 g/kg/d EBM/formula as per institutional feeding protocols
Day 3 3.5 g/kg/d 3 g/kg/d As above
≥Day 4 3.5 g/kg/d 3.5 g/kg/d As above
Week 2–4 Discontinue PN once full enteral feeds reached Evaluate growth and need for increased calorie intake/fortification
*Adjust electrolytes based on clinical and laboratory assessments.

†Monitor lipid levels when at 2 g fat/kg/d before increasing.


Guidelines for Initiating and Advancing Enteral Feeds in Stable Infants
Weight (g) Initiation of Feeds* Duration


Increase Feeds Days to Full Feeds
Bolus Continuous
500-750 0.5–1 mL q4h 72 N/A N/A 13-16


1 mL q2h 24 N/A N/A
Day 5-12: 1 mL q24h 0.5 mL q24h
Day 13: 1 mL q24h 0.5 mL q24h
750–1000 1 mL q4h 72 N/A N/A 13-16
1 mL q2h 24 N/A N/A
1 mL q24h 0.5 mL q24h
1000–1250 1 mL q2h 72 1 mL q12h 0.5 mL q12h 9
1250-1400 1 mL q2h 24 1 mL q12h 0.5 mL q12h 9
1400-1600 2 mL q2h 24 1 mL q8h 0.5 mL q8h 6-7
1600-1750 3 mL q3h 24 2 mL q9h 0.7 mL q9h 6-7
1750–2000 4 mL q3h 24 1 mL q3h 0.3 mL q3h 5-6
2000–2500 5 mL q3h 24 2 mL q3h 0.7 mL q3h 3-4
> 2500 6 mL q3h 24 3 mL q3h 1 mL q3h 3
For infants >48 h of age AND ≥2500 g
2500-400 6 mL q3h N/A 3 mL q3h 1 mL q3h 2-3
≥4000 g 6 mL q3h N/A 3-5 mL q3h 1-1.7 mL q3h 2-3
Infants >48 h of age AND born ≥37 wk GA AND BW ≥2500 g: Individualize feeding plan
Start 5-10 mL q3h and increase 5-8 mL q3h OR ad lib feeds with minimum TFI.
*Either as regular/slow bolus or as a continuous drip.

Days to full feeds = TFI ~150 mL/kg/day.


Initiation and Advancement of Enteral Feedings

Guidelines for Initiating & Advancing Feeds in Relatively Stable Infants


Initial Feed Volume*




Volume of increments


Frequency of Increments


< 750 0.5-1 1-2 0.5-1 ≥ 24
750-1000 1 2 1-2 12-24
1000-1500 1-2 2 1-2 ≥ 24
1500-2000 2-3 2-3 2-4 ≥ 12
2000-2500 4-5 3 3-5 ≥ 8
> 2500 10 3-4 7-10 ≥ 6

 *Either as a slow bolus or as a continuous drip.


Feeding Methods

Coordinated reflexes between sucking, swallowing and breathing are not fully developed until 33-35 weeks of gestation. Therefore some type of tube feeding is necessary to ensure enteral feeding and minimize duration of PN.

Intragastric tube feeding (orogastric or nasogasatric):

  • can be given by bolus (intermittent) or continuous infusion
  • choice of tube feeding depends on ventilatory status; considerations of apnea and ease of nursing
  • cautions and complications: Gastro-esophageal reflux; mal-position exacerbates this


Transpyloric tube feeding:

  • nutrition is delivered into the small intestines
  • feedings are given continuously
  • cautions and complications: mal-position and perforation; therefore not routinely recommended


Feeding Continuously or Intermittently

  • Available trials are poor in design and do not allow rigid recommendations.
  • Either is acceptable, consider switching if one unsatisfactory in individual infant


Feeding Tolerance

Poor agreement on definitions exists. Minor aspirates are frequent and not worrying.

More caution indicated when other signs present:

  • cardiovascular or respiratory instability – including apneas
  • marked abdominal distention
  • abdominal discoloration
  • emesis (consider frequency and volume)
  • blood in the stools or aspirate
  • increased stool frequency or diarrhea
  • bilious aspirates or emesis
  • excessive gastric residuals
    defined as: 20-50% of the previous bolus feed or 1- 1.5 times the hourly rate of continuous feeds or 2-3 mL per gastric residual


Feeding Selection

1. Human Milk and Human Milk Fortification

  • Human milk is the optimal food because of its nutritional, immunologic, endocrinologic, digestive and neuro-developmental advantages.
  • However, the milk of mothers of the more premature, smaller infant – is not optimal. To correct these nutritional inadequacies of human milk for very low birthweight preterm infants, either liquid or powdered human milk fortifiers can be added to provide additional protein, calories, minerals and vitamins; or the total volume of feed can be increased. Liquid fortifiers have a dilutional effect
  • Ensure adequate iron provided after 6 – 8 weeks of age for a total of 2-3 mg/kg/day until 12 months corrected age for BW>1000g and 3-4 mg/kg/day for BW<1000g.


Nutrient* Breastmilk*

(per 100/mL)

Enfamil Human Milk Fortifier

(per 4 packs)

Similac Human Milk Fortifier

(per 4 packs)

Energy kJ 280 59 59
   (kcal)   (67)   (14)   (14)
Protein (g) 0.9-1.2 1.1 1.0
Fat (g) 3.5 1.0 0.36
Carbohydrate (g) 6.7-7.2 0.4 1.8
Ca (mmol) 0.5-0.6 2.3 2.9
P (mmol) 0.4-0.5 1.6 2.2
Na (mmol) 0.5-1.1 0.7 0.6
K (mmol) 1.0-1.4 0.7 1.6
Cl (mmol) 1.1-1.3 0.4 1.1
Fe (mg) 0.03-0.09 1.44 0.35
Zinc (mol) 6.1 11.1 15
Vitamin D (IU) 2-4 150 120

 * Human milk composition – AAP 2003

Enfamil, Mead Johnson, Ottawa.  Four (4) packets to be added to 100 cc of human milk.


Preterm Formulas

  • Designed to meet the unique needs of hospitalized growing preterm infants.
  • Higher in protein and mineral content than term formulas.
  • Carbohydrate source is a combination of lactose and glucose polymers.
  • Contains 40-50% of the lipid as medium chain triglycerides (MCT) to improve fat absorption.
  • Whey predominant, cow’s milk-based.
  • Higher calcium, phosphorus and Vitamin D content for optimizing bone mineralization.


Table 8-10   Nutrient Content (per 100 mL) of Preterm Formulas Marketed in Canada
Nutrient Similac Advance Special Care 20 Similac Advance Special Care 24 Enfamil A+ Premature 20 Enfamil A+ Premature 24
Energy kJ 285 340 280 330
   (kcal)   (68)   (81)   (67)   (80)
Protein (g) 2.0 2.4 2.0 2.4
Fat (g) 3.7 4.4 3.4 4.1
Carbohydrate (g) 7.0 8.4 7.4 8.8
Na (mmol) 1.5 1.8 1.7 2.0
K (mmol) 2.1 2.5 1.7 2.0
Cl (mmol) 1.8 2.2 1.7 2.1
Ca (mmol) 2.5 3.0 2.8 3.4
P (mmol) 1.9 2.3 1.8 2.2
Fe (mg) 0.25/1.2 0.3/1.5 0.34/1.22 0.4/1.4
Vitamin A(IU) 686 814 838 1000
Vitamin D* (IU) 133 158 161 192
Vitamin E(IU) 2.1 2.5 4.2 5.0
DHA and AA yes yes yes yes
Nucleotides (mg) 7.2 7.2 2.8 3.4
Manufacturer Ross Abbot Laboritories Mead Johnson

 Low iron or with iron

Retinol equivalent (RE) = 3.33 IU

* 1 g Vit D (cholecalciferol) = 40 IU

1 mg Vit E (D-alpha tocopherol) = 1.49 IU


3. Term Formulas

  • In the absence of human milk, iron-fortified formulas are appropriate substitutes for full term infants.


Table 8.11   Nutrient Content (per 100 mL) of Term Formulas Marketed in Canada as Compared to Mature  Human Milk
Nutrient Enfamil A+

 (Enfalac Regular)

Similac Advance   with iron Good Start

(+ omega 3 & 6)

Mature Human Milk
Energy kJ 280 285 280 280
     (kcal)    (67)  (68)  (67)   (67)
Protein (g) 1.4 1.4 1.5 0.9-1.2
Fat (g) 3.6 3.7 3.4 3.5
Carbohydrate (g) 7.4 7.2 7.5 6.7-7.2
Na (mmol) 0.8 0.7 0.8 0.5-1.1
K (mmol) 1.9 1.8 1.9 1.0-1.4
Cl (mmol) 1.2 1.2 1.2 1.1-1.3
Ca (mmol) 1.3 1.3 1.1 0.5-0.6
P (mmol) 1.2 0.9 0.8 0.4-0.5
Fe (mg) 1.2 (0.45) 1.2 1.0 0.03-0.09
Vitamin A* (IU) 201 203 200 214
Vitamin D (IU) 41 41 40 2-4
Vitamin E(IU) 1.4 2.1 1.3 0.3
DHA & ARA yes (no) yes no (yes) yes
Manufacturer Mead Johnson Ross Abbot Lab. Nestle

* Retinol equivalent (RE) = 3.33 IU

1 g Vit D (cholecalciferol) = 40 IU

1 mg Vit E (D-alpha tocopherol) = 1.49 IU


4. Post Discharge Formulas

  • Nutrient enriched formulas designed for preterm infants after discharge from hospital
  • Provide higher intake of protein, calcium, phosphorus, Vitamin D, zinc and a greater protein-energy ratio, compared to term formulas
  • Infants receiving post-discharge formulas (PDF) exhibit better growth in weight, length, and head circumference
  • Infants <1000g and /or ≤ 29 weeks would benefit most and should be fed PDF until solids are introduced or at least until growth catch-up has occurred and /or biochemistry normalized



Table 8-12   Comparison of Sources of Nutrients for Post-Discharge Feeding of Ex- Premies

Per 100 mL Preterm Formula

(20/24 kcal/oz)

Post Discharge Formula Term Formula Breast Milk
Energy (kcal) 68/81 75-77 67 67
Protein (g) 2/2.4 1.9-2.1 1.4 1.0
Fat (g) 3.7/4.4 4.0-4.1 3.6 3.5
CHO (g) 7.0/8.4 7.7-8.0 7.4 6.8
Calcium (mmol) 2.8/3.4 1.9-2.2 1.3 0.65
Phosphorous (mmol) 1.8/2.2 1.4-1.5 1.0 0.45
Sodium (mmol) 1.7/2.0 1.1 0.8 0.9
Chloride (mmol) 1.7/2.1 1.5-1.6 1.1 1.6
Vitamin A (IU) 838/1000 330 200 222
Vitamin D (IU) 161/192 58 40 4.0
Iron (mg) 1.2/1.4* 1.3-1.4 1.0-1.2* 0.03
* Also available with low iron content


5. Specialty Formula

  • Soy protein based formula is not recommended for infants with birth weight <1800g.
  • Casein hydrolysate formulas are semi-elemental and hypoallergenic – use for
    • infants intolerant to cow’s milk or soy proteins
    • infants with significant fat malabsorption (use formula with MCT oil)
  • Amino-acid-based (elemental) formulas are indicated when symptoms persist after use of hydrolyzed protein formulas and in cases of severe malabsorption.
    • Infants with chylothorax may benefit from a formula with a high MCT content.


Nutrient Content (per 100 mL) of Special Formulas Marketed in Canada
Casein Hydrolysate Therapeutic Elemental Soy -Based
Nutrient Pregestimil Nutramigen Alimentum Portagen1 Neocate Prosobee Isomil
Energy kJ 280 280 285 280 280 280 285
     (kcal)  (67)  (67)  (68)  (67)  (67)  (67)  (68)
Protein (g) 1.9






2.4 2.1

(free amino acids)





Fat (g) 3.8 (53% MCT) 3.4 3.8 (33% MCT) 3.2 (86% MCT) 3.0 (LCT) 3.6 3.7
Carbohydrate (g) 6.8








7.8 7.0 7.0
Na (mmol) 1.2 1.1 1.3 1.4 1.1 1.0 1.3
K (mmol) 1.9 1.9 2.1 2.2 2.6 2.1 1.9
Cl (mmol) 1.6 1.4 1.5 1.6 1.5 1.5 1.2
Ca (mmol) 1.6 1.6 1.8 1.6 2.1 1.8 1.8
P (mmol) 1.4 1.4 1.6 1.5 2.0 1.8 1.6
Fe (mg) 1.2 1.2 1.2 1.3 1 1.2 1.2
Vitamin A* (IU) 211 201 203 530 211 210 200
Vitamin D (IU) 32 30 30 53 35 40 40
Vitamin E (IU) 1.6 1.4 2 2.1 0.8 1.3 1.7
Manufacturer Mead Johnson Mead Johnson Ross Abbot Mead Johnson SHS Mead Johnson Ross Abbot
1Note: In Canada, full strength Portagen is 30 kcal/oz therefore formula must be diluted to obtain 20 kcal/oz (or 67 kcal/100mL)

* Retinol equivalent (RE) = 3.33 IU

1 g Vit D (cholecalciferol) = 40 IU

1 mg Vit E (D-alpha tocopherol) = 1.49 IU


Special Considerations 

Short Bowel Syndrome: 

  • Advance early to ‘full’ amounts of protein and energy to facilitate gut repair.
  • Use continuous tube feeding to reduce osmotic load and absorptive workload per unit of time.
  • Start with human milk or a formula based on protein hydrolysates/amino acid mixtures, glucose polymers and MCT with some long chain fatty acids for essential fatty acids requirements.
  • Increase volume before concentration; initially diluted strength may be necessary.
  • Consider cycling TPN if partial parenteral nutrition is necessary.
  • Monitor serum electrolytes, acid-base status, iron, trace elements, fat-soluble vitamins and vitamin B12.
  • Monitor closely additional fluid, electrolytes, micronutrient losses (‘dumping’) from orogastric tube, stoma output and/or stool losses. Increase of stool/stoma volume by 50% or output > 40 cc/kg/day indicate diet adjustment needed.


Bronchopulmonary Dysplasia:

  • Increase energy for adequate growth, feeding up to 140-160 kcal/kg/day.
  • Fluid volume may need restriction, but may be difficult to accomplish because of risk for high renal solute load with high calorie feeding.
  • Minimize excessive CO2 production and respiratory load by lowering glucose:lipid caloric ratio in range 3:1 to 2:1.
  • Post-discharge nutrient-enriched formulas or supplemented human milk are needed to optimize bone health in the ELBW and possibly VLBW infant.


Patent Ductus Arteriosus (PDA) – Indomethacin:

  • Symptomatic PDA is accompanied with reduced, absent, or retrograde mesenteric diastolic blood flow velocities (‘steal’). Studies have yet to determine optimal feeding practices.
  • Fluid restriction for medical treatment of PDA is likely. It is prudent to withhold feeding when a patient has a hemodynamically significant PDA or is receiving indomethacin.


Small for Gestational Age (SGA) Infants:

  • Severe SGA infants tend to have feeding intolerance and may be at higher risk if fetal umbilical artery end diastolic blood flow was retrograde. Data poor.
  • Small amounts of human milk can be initiated early, while carefully monitoring tolerance. Usually some IV glucose is needed to prevent or treat hypoglycemia.
  • Increased energy intake may be needed to promote growth as SGA infants may have higher energy expenditure.
  • Whereas feeding nutrient-enriched formula may accomplish better growth than using term formula, only breastfed SGA term infants have the best neurodevelopmental outcome in short term studies.


Infants of Diabetic Mothers (IDM):

  • Hypoglycemia in IDM, is usually within 12 hours of birth; screening beyond 12 hours not required if blood glucose levels have been > 2.6 mmol/L.
  • Provide early, frequent feedings of mother’s milk or formula. Increased carbohydrate raises blood glucose; more importantly, enteral lipid intake stimulates glucagon and a drop in insulin production
  • If increased enteral caloric intake ineffective, start glucose infusion regime of 10% glucose at 80 mL/kg/day, increase stepwise as needed.
  • Advance oral feedings and reduce intravenous glucose slowly and simultaneously.
  • If still failing, glucagon raises glucose (0.1 to 0.3 mg/kg bolus or 10 to 20 mcg/kg/hour).
  • Watch for associated metabolic derangements such as hypocalcemia and hypomagnesemia.


Post Discharge Nutrition

Poor growth is a common problem for premature infants after discharge from hospital and may be related to weaning of nutritional supplements after discharge, early introduction of solid foods and cow’s milk. Therefore, it is important to include nutrition in discharge planning and to continue to nutritional assessment after discharge.

For infants discharged home on mother’s milk the following conditions should be met to ensure adequate growth or catch-up growth in the post discharge period: (a) the baby can consume > 180 mL/kg/d, (b) growth is adequate (weight, head circumference & length), and (c) simple biochemical nutritional indices are within the normal range, such as BUN (> 2 mmol/L), alkaline phosphatase (< 450 IU/L) and phosphorus (> 1.5 mmol/L). If these conditions are not fulfilled, one might have to consider fortification of the human milk for a few weeks until catch-up growth is established.

The use of post discharge formulas or hypercaloric formulas may be indicated for some premature infants who require further nutritional support in the post discharge period.


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