For children admitted to the pediatric intensive care unit (PICU) between 2020 and 2025, which nutrition screening tools (Pediatric Nutrition Screening Tool (pNST) and Pediatric Subjective Global Nutritional Assessment (SGNA)) should be used and what evidence‑based nutrition interventions are recommended for those identified as malnourished?

Nutrition Screening and Assessment in the PICU (2020-2025)

All children admitted to the PICU should undergo nutritional status assessment within 24-48 hours of admission using anthropometric measurements expressed as z-scores, followed by comprehensive nutritional assessment for those identified at risk, with early enteral nutrition initiated within 24 hours unless contraindicated. 1

Recommended Screening Approach on PICU Admission

Initial Anthropometric Measurements (Within 24-48 Hours)

• Measure and document weight and height/length with z-scores calculated for BMI-for-age (or weight-for-length if <2 years) 1, 2
• Document head circumference in all children <36 months 1, 2
• Measure mid-upper arm circumference (MUAC) 1, 2
• Express all measurements as z-scores rather than percentiles for greater precision 1

Validated Screening Tools: Current Evidence and Limitations

No pediatric nutrition screening tool has been validated specifically for the PICU population or with respect to clinical outcomes such as morbidity, mortality, or quality of life. 2, 3 However, the following tools have moderate validity in general pediatric populations:

Pediatric Nutrition Screening Tool (PNST)

• Sensitivity of 77.8% and specificity of 82.1% compared to SGNA in general pediatric wards 4
• Identified 37.6% of hospitalized children as at nutrition risk 4
• Higher sensitivity (88.9%) for detecting stunting (height-for-age) 5
• Simple 4-question format designed for rapid bedside use 4
• In PICU settings, PNST alone had poor specificity (0.06) when incorporated into electronic screening systems 3

Subjective Global Nutritional Assessment (SGNA)

• SGNA is a comprehensive assessment tool, not a screening tool 6
• Stronger agreement with objective malnutrition parameters (k=0.337) than STAMP (k=0.052) 6
• 4-fold higher specificity (70.45%) than STAMP (18.18%) in detecting malnourished children 6
• Identified 45% of hospitalized children at malnutrition risk 6
• Should be used as the follow-up assessment tool after positive screening, not as the initial screen 6

Other Screening Tools

• PYMS (Pediatric Yorkhill Malnutrition Score) showed relatively higher sensitivity of 90.9% for weight-for-age and 84.6% for BMI-for-age 5
• STRONGkids has moderate validity but lower specificity 2, 5

Comprehensive Nutritional Assessment for At-Risk Patients

For all patients identified as at-risk through screening, conduct comprehensive nutritional assessment within 48 hours including: 1, 2

• Medical and dietary history with focus on recent weight loss percentage 2
• Duration and severity of reduced food intake 2
• Physical examination for signs of malnutrition (muscle wasting, subcutaneous fat loss, edema) 2
• Underlying disease severity assessment 2
• Biochemical markers if indicated (C-reactive protein, total lymphocytes, serum albumin) 6

Evidence-Based Nutrition Interventions for Malnourished PICU Patients

Timing and Route of Nutrition Support

Initiate early enteral nutrition within 24 hours of PICU admission unless contraindicated 1

• Early EN (within 24-48 hours) is associated with improved clinical outcomes including shorter ventilation duration, lower infection rates, and reduced mortality 1
• Enteral nutrition is the preferred mode of nutrient delivery over parenteral nutrition 1

Advancement Strategy

Increase enteral nutrition in a stepwise fashion using a feeding protocol or guideline until goal delivery is achieved 1

• Feeding protocols improve time to initiation of EN and nutritional intake (Grade C evidence) 1
• For high-risk populations, feeding protocols reduce adverse events (Grade D evidence) 1
• Achievement of up to two-thirds of nutrient goal in the first week is associated with improved outcomes 1

Special Populations in PICU

Early enteral nutrition is recommended in the following hemodynamically unstable populations once stabilized: 1

• Children stable on vasoactive medications (Grade D evidence) 1
• Children stable on ECLS/ECMO (Grade D evidence) 1
• Children after cardiac surgery (Grade C evidence) 1
• Term neonates on pharmaceutical hemodynamic support (GCP recommendation) 1

Parenteral Nutrition Timing

Withholding parenteral nutrition for up to one week can be considered in critically ill term neonates and children, independent of nutritional status, while providing micronutrients (Grade B evidence) 1

• This represents a departure from older recommendations and is based on recent high-quality evidence 1
• Micronutrients must still be provided during this period 1

Route of Enteral Feeding

Gastric feeding is as safe as post-pyloric feeding in the majority of critically ill children (Grade C evidence) 1

• Post-pyloric feeding should be reserved for children at high risk of aspiration or requiring frequent fasting for procedures (GCP recommendation) 1
• Routine measurement of gastric residual volumes is not recommended (Grade D evidence) 1

Ongoing Monitoring Requirements

Re-evaluate nutritional status at least weekly throughout PICU hospitalization 1, 2

• Children are at risk of nutritional deterioration during hospitalization which adversely affects clinical outcomes 1, 2
• Repeat anthropometric measurements regularly during admission 1
• Muscle wasting occurs rapidly in critically ill children and requires ongoing assessment 1

Critical Pitfalls to Avoid

Do not rely solely on BMI or single anthropometric measurements 2

• Single measurements miss many at-risk children and fail to predict complications 2

Do not use adult screening tools (NRS-2002, MUST, MNA) in children 2

• These are designed for adult populations and not validated in pediatrics 2

Do not assume screening tools alone are sufficient 2, 6

• Screening must be followed by comprehensive assessment for positive screens 2, 6
• SGNA should verify actual nutrition status after positive STAMP or PNST screens 6

Do not delay EN initiation due to hemodynamic instability in stable patients 1

• Once stabilized on vasoactive support or ECLS, EN should be initiated 1

Do not routinely use prokinetics 1

• Insufficient evidence supports their use to improve gastric emptying and feed tolerance (GCP recommendation) 1

Clinical Impact of Malnutrition in PICU

Malnutrition (15-25% prevalence at PICU admission) is associated with: 1, 2

• Longer periods of mechanical ventilation 1, 2
• Higher risk of hospital-acquired infections 1, 2
• Longer PICU and hospital length of stay 1, 2
• Increased mortality 1, 2
• Up to 40% of hospitalized children with chronic conditions are affected 2