Neonatal and Pediatric Nutritional Requirements

Maintenance vs. Growth Fluid Requirements in Infants

• Maintenance Fluids: These are defined as the volume of fluid required to ensure homeostasis, as well as maintaining proper cardiovascular and renal function.

• Growth Fluids: This requirement represents a different volume than maintenance. It is the amount of fluid necessary to provide the optimal levels of calories, protein, and micronutrients to ensure a patient is actively growing.

• Nutrient Intake through Liquid: Infants take in all of their nutrition through liquid form. Consequently, it is critical that their fluid intake levels are slightly higher to ensure they receive a complete profile of required nutrients.

Neonatal Fluid Needs and Management

• Post-natal Fluid Limitation: In the immediate post-natal period, fluid intake is initially limited to allow for naturally occurring diuresis. Following this period, fluid administration can be liberalized.

• Estimation of Maintenance Needs: The Holliday-Segar equation can be utilized to estimate maintenance fluid requirements at approximately $100\,mL/kg$.

• Goal Fluid Volumes for Growth: To support growth, goal fluid volumes generally range between $140\text{--}200\,mL/kg/d$.

Nutritional Challenges for Preterm Infants

• Nutritional Reserves: Preterm infants are born with little to no nutritional reserves.

• Catabolic State: Due to the lack of reserves and increased energy expenditure, these infants immediately enter a catabolic state post-birth.

• Determining Energy Needs: It is helpful to compare multiple predictive equations to determine and select the specific range of energy needs for a patient.

Late Pre-term Energy and Protein Needs

• Late Pre-term Considerations: These infants are associated with unique nutritional issues, including difficulties with feeding and the frequent need for respiratory support, which further complicates the ability to feed.

• ASPEN Classification: ASPEN (American Society for Parenteral and Enteral Nutrition) is one of the few guidelines that further differentiates preterm classifications into "pre-term" and "late pre-term."

ASPEN Late Pre-term Nutritional Recommedations:

• Enteral Energy Needs: $120\text{--}135\,kcal/kg/d$

• Enteral Protein Needs: $3\text{--}3.2\,gm/kg/d$

• Parenteral Energy Needs: $100\text{--}110\,kcal/kg/d$

• Parenteral Protein Needs: $3\text{--}3.5\,gm/kg/d$

Nutritional Requirements for Term Infants (Enteral)

• ASPEN Guidelines: Energy: $105\text{--}120\,kcal/kg/d$; Protein: $2\text{--}2.5\,gm/kg/d$

• Texas Children’s: Energy: $100\text{--}130\,kcal/kg$; Protein: $1.5\,gm/kg/d$ (for healthy infants) or $2\text{--}3\,gm/kg/d$ (for ill infants).

• CSPEN: Energy: $105\text{--}130\,kcal/kg/d$; Protein: $2\text{--}3\,gm/kg/d$

• ESPGHAN Critical Care Guidelines (2021) - Recovery Phase: Energy: $90\text{--}120\,kcal/kg/d$; Protein: $2\text{--}3.5\,gm/kg/d$

Nutritional Requirements for Term Infants (Parenteral)

• ASPEN Guidelines: Energy: $90\text{--}108\,kcal/kg/d$; Protein: $2.5\text{--}3\,gm/kg/d$

• NICE PN Guidelines: Recommends starting at the low end of recommendations for preterm infants and advancing to maintenance intake levels.

• Texas Children’s: Energy: $90\text{--}110\,kcal/kg/d$; Protein: $1.5\text{--}3\,gm/kg/d$

• ESPGHAN Critical Care Guidelines (2021) - Recovery Phase: Energy: $75\text{--}85\,kcal/kg/d$; Protein: $2\text{--}3\,gm/kg/d$

Needs for Infants with NOWS/NAS

• Energy Requirements: Infants with Neonatal Opioid Withdrawal Syndrome (NOWS) or Neonatal Abstinence Syndrome (NAS) may require early fortification to $22\text{--}24\,kcal/oz$. Their energy needs can reach as high as $150\,kcal/kg$.

• Fluid Considerations: Special consideration must be given to the loss of fluids through symptoms like diarrhea or vomiting.

Respiratory Distress Syndrome (RDS) and Bronchopulmonary Dysplasia (BPD) Needs

RDS Recommendations:

• Energy (Parenteral): $85\text{--}115\,kcal/kg$

• Energy (Enteral): $90\text{--}130\,kcal/kg$

• Protein: $3.5\text{--}4\,g/kg$

• Fluid: $120\text{--}150\,mL/kg$

BPD Recommendations:

• Energy: Requires a $15\text{--}25\%$ increase in energy needs, totaling $135\text{--}150\,kcal/kg/d$. Total Energy Expenditure (TEE) is directly related to respiratory status.

• Protein: The goal is $3.5\,gm/kg/d$. Enteral protein goals align with ESPGHAN recommendations.

• Fluid: May be restricted to $135\text{--}150\,mL/kg/d$ to prevent fluid overload.

Extracorporeal Membrane Oxygenation (ECMO) Nutritional Needs

• Energy Gold Standard: Indirect calorimetry is considered the gold standard for determining energy needs.

• Predictive Models: WHO or Schofield equations can be considered.

• Energy Guidelines:

  • ASPEN: $100\text{--}120\,kcal/kg/d$

  • Neonatal Nutrition Pocket Guide (Minimal Metabolic Support): $80\text{--}100\,kcal/kg/d$

• Protein: $3\,gm/kg/day$

• Fluid Management: Volumes may be strictly limited. Clinicians must account for fluid per kilogram from drips. Parenteral Nutrition (PN) volumes may be limited to $60\text{--}80\,mL/kg$ with total goals of $120\text{--}130\,mL/kg$.

Congenital Heart Disease (CHD) and Renal Disease Needs

CHD Recommendations:

• Fluid: $120\text{--}130\,mL/kg/day$

• Energy: $130\text{--}150\,kcal/kg/day$

• Protein (Pre-term): $3.5\text{--}4\,gm/kg/day$

• Protein (Term): $1.8\text{--}2.2\,gm/kg/day$

Renal Disease Recommendations:

• Overview: Needs depend on whether the disorder is acute or chronic and the specific clinical scenario. Energy needs are generally similar to standard enteral or parenteral needs.

• Pre-term Infants: Needs are consistent with standard pre-term goals for both calories and protein.

• Term Infants (0-6 months) Protein Goals by Severity:

  • CKD Stage 3: $1.5\text{--}2.1\,gm/kg$ ($100\text{--}140\%$ DRI)

  • CKD Stage 4-5: $1.5\text{--}1.8\,gm/kg$ ($100\text{--}120\%$ DRI)

  • Hemodialysis: $1.6\,gm/kg$ (DRI + $0.1\,gm/kg$)

  • Peritoneal Dialysis: $1.8\,gm/kg$ (DRI + $0.3\,gm/kg$)

Surgical Nutritional Recommendations

• Energy Needs:

  • Full term infant: $100\text{--}120\,kcal/kg$

  • Pre-term infant: $110\text{--}160\,kcal/kg$

• Protein Needs:

  • Term infant: $2.5\text{--}3\,gm/kg$

  • Pre-term infant: $3.5\text{--}4\,gm/kg$

• Caveats: Needs may increase due to malnutrition, wound healing, or increased losses via an ostomy.

Case Study 1: Baby Boy B

Patient Profile:

• History: ex-$33wk4d$ born to a G2P1 mother via vaginal delivery.

• Diagnosis: Admitted to NICU for Respiratory Distress Syndrome (RDS).

• Current Support: Bubble CPAP.

• IV Access: Starter TPN initiated via peripheral IV; PICC placement planned. Custom TPN bag planned for tonight.

Anthropometrics and Growth (Fenton Growth Chart):

• Birthweight: $1812\,grams$ ($1.812\,kg$); $20^{th}$ percentile; Z-score: $-0.84$

• Length: $46\,cm$; $77^{th}$ percentile; Z-score: $0.73$

• Head Circumference: $30\,cm$; $30^{th}$ percentile; Z-score: $-0.51$

Nutritional Need Estimations (Goal PN and EN):

• Parenteral Nutrition (PN) Goals:

  • Energy: $85\text{--}111\,kcal/kg/d$

  • Calculated range: $(85\,kcal/kg \times 1.812\,kg) = 154\,kcal$ to $(111\,kcal/kg \times 1.812\,kg) = 201\,kcal$

  • Protein: $3\text{--}4\,gm/kg$

  • Calculated range: $(3\,gm/kg \times 1.812\,kg) = 5.4\,g$ to $(4\,gm/kg \times 1.812\,kg) = 7.2\,g$

• Enteral Nutrition (EN) Goals:

  • Energy: $110\text{--}130\,kcal/kg/d$

  • Calculated range: $(110\,kcal/kg \times 1.812\,kg) = 199\,kcal$ to $(130\,kcal/kg \times 1.812\,kg) = 236\,kcal$

  • Protein: $3.5\text{--}4.5\,gm/kg$

  • Calculated range: $(3.5\,gm/kg \times 1.812\,kg) = 6.3\,g$ to $(4.5\,gm/kg \times 1.812\,kg) = 8.2\,g$