Malnutrition (Undernutrition) — Criteria for Diagnosing Malnutrition in Preterm Infants < 1 Month Corrected and Term Infants < 1 Month Old — Clinical Pathway: Inpatient

Malnutrition (Undernutrition) Clinical Pathway — Inpatient

Criteria for Diagnosing Malnutrition in Preterm Infants < 1 Month Corrected and Term Infants < 1 Month Old

The following table and selection criteria provided should be used for infant < 1 month corrected (for infants born < 37 weeks gestational age) and < 1 month old (for infants born > 37 weeks gestational age).

Indicator Mild Malnutrition Moderate Malnutrition Severe Malnutrition Notes
Nutrient Intake
Only indicator appropriate for infants ≤ 2 weeks
Not recommended in infants < 1 week old
  • ≥ 3-5 consecutive days of protein/energy intake
  • ≤ 75% of estimated needs
  • ≥ 5-7 consecutive days of protein/energy intake
  • ≤ 75% of estimated needs
  • > 7 consecutive days of protein/energy intake
  • ≤ 75% of estimated needs
  • Use Clinical Judgement to Adjust Estimated Needs PRN
    • Preterm:
      • EN: 110-130 kcal/kg
      • PN: 100-110 kcal/kg
      • Protein: 3-4 g/kg/day
    • Term:
      • EN: 108 kcal/kg
      • PN: 90-100 kcal/kg
      • Protein: 1.5-2 g/kg/day
Decline in Weight-for-age
Z-score		 Decline of 0.8-1.2 SD Decline of > 1.2-2 SD Decline of > 2 SD Helpful Tips
Weight Gain Velocity < 75% of expected rate < 50% of expected rate < 25% of expected rate
  • Preterm infants:
    roughly 15-20 g/kg/day
  • Consider using online calculator   until > 37 weeks PMA then use WHO weight velocity standards

Indicators Below Require the Use of 2 or More Indicators

Indicator Mild Malnutrition Moderate Malnutrition Severe Malnutrition Notes
Days to Regain BW 15-18 19-21 > 21 Must use with nutrient intake
Linear Growth Velocity < 75% of expected rate < 50% of expected rate < 25% of expected rate
  • Defer in critically ill, unstable infants
  • Only use if length measure is thought to be accurate
Decline in Length-for-age Z-score Decline of 0.8-1.2 SD Decline of > 1.2-2 SD Decline of > 2 SD

Helpful Tips

Definitions and Plotting

  • Preterm infants: Born 36 6/7 weeks gestational age or earlier
    • Plot using the Fenton 2013 Preterm Growth Chart until 40 weeks then use WHO growth chart
    • Use corrected age
  • Term infants: Born 37 weeks gestational age or later
    • Plot using WHO growth chart
    • Use chronological age

Anthropometrics

  • Accurate anthropometric measurements must be obtained
  • Consider other factors that could affect weight or length measurements (especially when diagnosing malnutrition using Z-scores): fluid changes, edema, bed scales, different scales, +/- equipment, etc.

Weight Gain Velocity

  • Typically based on the 50th percentile of WHO weight velocity growth standards for term infants to maintain growth rate, but adjust based on clinical judgement