Overview
Definition:
Breast milk fortifiers (BMFs) are nutritional supplements added to human milk to increase its energy and nutrient content, primarily to meet the enhanced needs of very low birth weight (VLBW) infants (birth weight < 1500g) for optimal growth and development
These infants have immature digestive systems, increased metabolic demands, and higher risk of nutritional deficiencies.
Epidemiology:
VLBW infants constitute a significant proportion of neonatal admissions requiring specialized care
Nutritional support is critical, with approximately 10-15% of VLBW infants experiencing growth faltering in the NICU
The need for fortification arises due to the nutrient density of term breast milk being insufficient for the accelerated growth rates required by preterm infants.
Clinical Significance:
Appropriate selection and use of BMFs are crucial for preventing malnutrition, supporting neurodevelopment, reducing the risk of morbidities like necrotizing enterocolitis (NEC) and late-onset sepsis, and improving long-term outcomes in VLBW infants
Inadequate fortification can lead to growth failure, bone demineralization, and impaired immune function, directly impacting their transition to extrauterine life and future health.
Nutritional Needs Of Vlbw Infants
Energy Requirements:
Estimated daily energy needs range from 110-130 kcal/kg/day to support catch-up growth and basal metabolic rate.
Protein Requirements:
Higher protein needs of 3.5-4.5 g/kg/day are essential for tissue synthesis and growth, compared to term infants.
Fat Requirements:
Essential for energy, essential fatty acid intake, and absorption of fat-soluble vitamins
typically 4.5-5.5 g/kg/day.
Micronutrient Requirements:
Increased requirements for calcium, phosphorus, iron, zinc, copper, selenium, and vitamins (especially A, D, E, K, and B vitamins) due to immature absorption, increased losses, and rapid growth.
Fluid Requirements:
Careful fluid management is necessary, typically 120-160 mL/kg/day, balancing hydration with the risk of fluid overload.
Types Of Breast Milk Fortifiers
Human Milk Based Fortifiers:
Derived from pooled human milk, these provide a more 'biologically active' profile with immune factors and are generally better tolerated
They offer a spectrum of human-derived proteins, fats, and carbohydrates.
Multi Nutrient Fortifiers:
These are powdered or liquid supplements, often cow milk-derived, that are mixed with expressed breast milk
They contain a blend of macronutrients (protein, carbohydrates, fats) and micronutrients (vitamins, minerals) to enhance the nutritional profile.
Specialized Fortifiers:
Formulations designed for specific needs, such as those with increased protein or specific mineral content, or those for infants with malabsorption issues.
Selection Criteria For Bmfs
Infant Gestational Age And Weight:
Fortifiers should be chosen based on the infant's gestational age and current weight, with specific formulations often available for different birth weight categories.
Nutritional Status And Growth Rate:
Assessment of the infant's current growth trajectory and evidence of nutritional deficiencies will guide the choice and dose of fortifier.
Gastrointestinal Tolerance:
Consideration of previous feeding intolerance, presence of NEC, or abdominal distension
Human milk-based fortifiers are often preferred for initial trials due to better tolerance.
Availability And Cost:
The availability of different fortifier types and their cost-effectiveness for the institution are practical considerations.
Institutional Protocols And Guidelines:
Adherence to established neonatal unit protocols for BMF use ensures standardization and evidence-based practice.
Administration And Monitoring
Method Of Fortification:
Fortifiers are typically added to freshly expressed breast milk just before feeding
The amount of fortifier is adjusted based on the volume of milk and the desired nutrient concentration.
Feeding Strategies:
Fortified breast milk can be given via nasogastric or orogastric tube, or orally, depending on the infant's feeding ability
Gradual advancement of feeds is important.
Monitoring Growth:
Regular monitoring of weight, length, and head circumference is essential, with target growth rates often set at 2-3 g/kg/day for weight, 0.8-1 cm/week for length, and 0.5-0.7 cm/week for head circumference.
Monitoring Biochemical Parameters:
Periodic monitoring of serum electrolytes, calcium, phosphorus, alkaline phosphatase, and iron indices helps assess nutritional status and identify deficiencies or excesses.
Potential Challenges And Complications
Gastrointestinal Intolerance:
Symptoms may include abdominal distension, increased residuals, vomiting, or diarrhea
This might necessitate a change in the fortifier type or reduction in fortification level.
Mineral Imbalances:
Over-fortification with calcium or phosphorus can lead to hypercalcemia or hyperphosphatemia
Conversely, inadequate fortification can cause rickets.
Iron Deficiency:
Despite fortification, iron stores can be depleted
Adequate iron supplementation is crucial, especially beyond 4-8 weeks of age.
Bone Mineralization Issues:
Rickets of prematurity can occur if calcium and phosphorus intake is insufficient or absorption is impaired
Monitoring alkaline phosphatase is important.
Infection Risk:
While human milk has protective factors, any manipulation of feeds carries a small risk of contamination
Strict aseptic techniques are paramount.
Key Points
Exam Focus:
DNB/NEET SS exams will focus on calculating BMF needs based on infant weight, gestational age, and target growth parameters
Understanding the role of each nutrient and common deficiencies is critical
Know the typical energy and protein requirements for VLBW infants.
Clinical Pearls:
Always start with the least expensive and best-tolerated fortifier (often human milk-based if available)
Monitor for signs of intolerance and adjust fortification gradually
Collaborate with the neonatal dietitian for individualized plans.
Common Mistakes:
Under-fortifying breast milk, leading to poor growth
Over-fortifying, leading to metabolic derangements
Not monitoring for gastrointestinal intolerance
Inadequate monitoring of growth and biochemical parameters
Failing to adjust fortification as infant grows.