Table 2. Suggested Guidelines for Monitoring and Managing PN-associated MBD
1. Evaluate all patients receiving long-term PN (>1 yr) for MBD
2. Monitor for physical signs of MBD: lost of height, bone or back pain.
3. Provide adequate amounts of minerals in the PN solution for bone remodeling, including calcium (~15 mEq), phosphorus (~15 mmol), and magnesium (adjust amount per serum and urine levels).
4. Reduce higher protein doses to 1 g/kg/d once nutritional status is improved and proteins are repleted.
5. Treat metabolic acidosis with adequate amounts of acetate in the PN solution to avoid calcium carbonate mobilization from bone to buffer excess acid.
6. Monitor blood studies (at least monthly) to evaluate calcium, phosphorus, magnesium, and acetate levels. Maintain normal serum levels by adjusting amounts in the PN solution. Specific markers of bone metabolism may be of further diagnostic help.
7. Obtain 24-hour urine collection for calcium and magnesium every 6 to 12 months. Adjust PN to maintain positive balances.
8. Obtain DXA measurement and refer patient to endocrinologist for evaluation and pharmacologic treatment if there is low bone mineral density (T-score below –1). Repeat DXA every 1 to 2 years.
9. Minimize steroid use and all medications known to cause bone resorption.
10. Promote exercise or refer to physical therapist.
11. Encourage cessation of smoking.