When should a 22 calorie (cal) formula be changed?

When to Change 22 Calorie Formula

Change a 22 calorie formula when the infant demonstrates feeding intolerance (vomiting, diarrhea, abdominal distension, gastric retention), inadequate growth despite adequate volume intake, or when transitioning from specialized nutritional needs back to standard feeding as clinical condition improves. 1, 2

Clinical Indications for Formula Change

Signs of Feeding Intolerance Requiring Formula Modification

• Upper gastrointestinal symptoms (vomiting, gastric retention) should prompt consideration of caloric density, protein form, and osmolality of the current formula 2
• Lower gastrointestinal symptoms (diarrhea, abdominal distension) require assessment of fiber source, osmolality, and protein form 2
• Slow transition to calorically dense formulas improves tolerance, so rapid advancement should be avoided 1
• Monitor for decreased gastric emptying and gastroesophageal reflux, which can occur with higher fat content in concentrated formulas 1

Growth and Nutritional Adequacy Considerations

• If an infant on 22 kcal/oz formula is not achieving adequate "catch-up" weight gain, consider increasing to 24-30 kcal/oz for infants with higher energy requirements 1
• For infants with chronic lung disease or other conditions requiring elevated calories, intake may need to increase to 150 kcal/kg/day or more, necessitating formula adjustment 1
• Conversely, as clinical condition improves and energy requirements normalize, transition back toward standard 20 kcal/oz formula 1, 3

Metabolic and Renal Considerations

• Protein intake must be monitored carefully: young infants should receive no more than 4 g/kg/day of protein due to risk of acidosis related to immature kidneys 1, 4
• Maintain appropriate protein levels (3 g/kg/day in early infancy to 1.2 g/kg/day in early childhood) when adjusting caloric density 1
• Micronutrient assessment is necessary when changing formulas, as concentrated formulas may require vitamin and mineral supplementation if providing less than 100% of the Recommended Dietary Allowance 1

Formula Selection Algorithm When Change is Indicated

For Severe Malabsorption or GI Dysfunction

• Start with elemental formulas (like Tolerex) due to lowest osmolality (approximately 215 mOsm/kg H₂O) and free amino acid composition 4
• These formulas minimize osmotic diarrhea risk while providing adequate nutrition 4

For Moderate Malabsorption

• Consider peptide-based formulas (like Peptamen Junior) with medium-chain triglycerides, which have moderate osmolality (315-370 mOsm/kg H₂O) 4
• Fat-modified formulas containing medium-chain triglycerides, carnitine, and taurine improve feeding tolerance in patients with digestive challenges 5

For Normal Digestive Function Requiring Nutritional Support

• Standard intact protein formulas (like PediaSure) are appropriate, though osmolality is higher (390-405 mOsm/kg H₂O) 4
• Ensure osmolality remains below 450 mOsm/L as recommended by the American Academy of Pediatrics to reduce osmotic diarrhea risk 4

Critical Pitfalls to Avoid

• Never rapidly advance formula concentration, especially with higher osmolality products, as this increases risk of feeding intolerance 4, 2
• Do not attribute all feeding intolerance to the formula itself—assess concomitant medications, malnutrition/hypoalbuminemia, and bacterial contamination as contributing factors 6
• Avoid changing formulas as the first-line strategy for feeding intolerance; consider elevating head of bed, adjusting infusion rate, volume, or feeding regimen first 2
• Do not overlook that medications and carbohydrate modules added to formulas can significantly increase osmolality beyond safe limits 4

Monitoring During Formula Transition

• Add food coloring to feedings to help detect aspiration or tube displacement 6
• Check urine sugar and acetone every 6 hours until stable 6
• Monitor vital signs and fluid intake/output every 8 hours 6
• Measure daily weight and assess serum electrolytes, blood urea nitrogen, and glucose daily until levels stabilize 6
• Flush feeding tubes with water every 4 hours during continuous feedings to prevent obstruction 6