Calcium Dosing in Children by Body Weight
For parenteral nutrition, calcium dosing varies by age: preterm infants require 32-80 mg/kg/day initially and 64-140 mg/kg/day when growing; term infants 0-6 months need 30-60 mg/kg/day; infants 7-12 months need 20 mg/kg/day; and children 1-18 years require 10-16 mg/kg/day. 1
Parenteral Nutrition Dosing (Primary Guideline)
The ESPGHAN/ESPEN/ESPR/CSPEN 2018 guidelines provide the most comprehensive age-stratified recommendations for calcium administration in children receiving parenteral nutrition 1:
Preterm Infants
- First days of life: 0.8-2.0 mmol/kg/day (32-80 mg/kg/day) 1
- Growing premature infants: 1.6-3.5 mmol/kg/day (64-140 mg/kg/day) 1
- Individual requirements depend heavily on growth velocity (5-20 g/kg/day), with some infants requiring up to 4.0 mmol/kg/day (160 mg/kg/day) 1
- Very low birth weight infants need careful monitoring as they are at high risk for early hypophosphatemia and subsequent hypercalcemia 1
Term Infants and Young Children
- 0-6 months (includes term newborns): 0.8-1.5 mmol/kg/day (30-60 mg/kg/day) 1
- 7-12 months: 0.5 mmol/kg/day (20 mg/kg/day) 1
- These recommendations assume 50-60% absorption rates for calcium when extrapolating from breastfed infant data 1
Older Children
- 1-18 years: 0.25-0.4 mmol/kg/day (10-16 mg/kg/day) 1
- For children on long-term parenteral nutrition, higher doses up to 0.35-0.4 mmol/kg/day may prevent metabolic bone disease 1
Critical Monitoring Considerations
Children on long-term parenteral nutrition require periodic monitoring of calcium, phosphorus, vitamin D, and bone mineral status to prevent metabolic bone disease, which can progress from osteopenia to severe bone disease with fractures. 1
Key Pitfalls to Avoid
- Aluminum contamination: Intake should not exceed 5 mg/kg/day, as aluminum toxicity contributes to metabolic bone disease 1
- Calcium-phosphorus precipitation: Use organic phosphorus compounds or carefully sequence mixing to prevent precipitation in parenteral solutions 1
- Hypercalciuria: Monitor urinary calcium, as negative calcium balance and hypercalciuria are potential complications that can lead to nephrocalcinosis 1
Acute Emergency Dosing
For emergency treatment of hypocalcemia, hyperkalemia, hypermagnesemia, or calcium channel blocker toxicity 1:
- IV/IO calcium chloride: 20 mg/kg (0.2 mL/kg of 10% solution) 1
- Administer slowly for cardiac arrest; infuse over 30-60 minutes for other indications 1
- Central venous access is preferred as extravasation causes severe tissue injury 1
Oral Supplementation Context
While the question asks about dosing per kg, oral calcium recommendations differ significantly from parenteral dosing due to absorption differences 1. For specific conditions like X-linked hypophosphatemia, oral elemental phosphorus dosing of 20-60 mg/kg/day (0.7-2.0 mmol/kg/day) is recommended, taken 4-6 times daily in young patients 1. However, routine calcium supplementation is not recommended in most children with adequate dietary intake 1.